Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 Network Working Group Jonathan P. Lang, Editor Internet Draft Expiration Date: December 2002 June 2002 Link Management Protocol (LMP) draft-ietf-ccamp-lmp-04.txt Status of this Memo This document is an Internet-Draft and is in full conformance with all provisions of Section 10 of RFC2026 [RFC2026]. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet- Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. Abstract Optical networks are being developed to include photonic switches, optical crossconnects, and routers that are configured with control channels and data links. Furthermore, multiple data links may be combined to form a single traffic engineering (TE) link for routing purposes. This draft specifies a link management protocol (LMP) that runs between neighboring nodes and is used to manage TE links. Specifically, LMP will be used to maintain control channel connectivity, verify the physical connectivity of the data-bearing channels, correlate the link property information, suppress downstream alarms, and localize link failures for protection/restoration purposes in both opaque and transparent networks. Lang et al [Page 1]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 Table of Contents 1 Introduction ................................................ 4 2 LMP Overview ................................................ 5 3 Control Channel Management ................................... 7 3.1 Parameter Negotiation ................................... 8 3.2 Hello Protocol ........................................... 9 3.2.1 Hello Parameter Negotiation ....................... 9 3.2.2 Fast Keep-alive .................................. 10 3.2.3 Control Channel Down ............................. 11 3.2.4 Degraded (DEG) State ............................. 11 4 Link Property Correlation ................................... 11 5 Verifying Link Connectivity ................................. 13 5.1 Example of Link Connectivity Verification ............... 16 6 Fault Management ............................................ 17 6.1 Fault Detection ......................................... 17 6.2 Fault Localization Procedure ............................ 18 6.3 Examples of Fault Localization .......................... 18 6.4 Channel Activation Indication ........................... 19 6.5 Channel Deactivation Indication ......................... 20 7 Message_Id Usage ............................................ 20 8 Graceful Restart ............................................ 21 9 Addressing .................................................. 22 10 Exponential Back-off Procedures ............................. 23 10.1 Operation.................................................. 23 10.2 Retransmission Algorithm .................................. 23 11 IANA Considerations ......................................... 24 12 LMP Finite State Machines ................................... 24 12.1 Control Channel FSM .................................... 24 12.1.1 Control Channel States .......................... 24 12.1.2 Control Channel Events .......................... 25 12.1.3 Control Channel FSM Description ................. 28 12.2 TE Link FSM ............................................ 29 12.2.1 TE link States .................................. 29 12.2.2 TE link Events .................................. 29 12.2.3 TE link FSM Description ......................... 30 12.3 Data Link FSM .......................................... 30 12.3.1 Data Link States ................................ 31 12.3.2 Data Link Events ................................ 31 12.3.3 Active Data Link FSM Description ................ 33 12.3.4 Passive Data Link FSM Description ............... 34 13 LMP Message Formats ......................................... 35 13.1 Common Header .......................................... 35 13.2 LMP Object Format ...................................... 36 13.3 Parameter Negotiation .................................. 37 13.4 Hello .................................................. 39 13.5 Link Verification ...................................... 39 13.6 Link Summary ........................................... 43 13.7 Fault Management ....................................... 44 14 LMP Object Definitions ...................................... 45 15 Security Conderations ....................................... 63 16 Intellectual Property Considerations ........................ 63 17 References .................................................. 63 Lang et al [Page 2]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 18 Acknowledgments ............................................. 64 19 Contributors ................................................ 65 20 Contact Address ............................................. 65 Lang et al [Page 3]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 Changes from previous version: o Editorial changes. o Changed LMP from running directly over IP to running over UDP. o Added Section describing exponential back-off procedures. o Added suggested values for timers. o Merged the LOCAL/REMOTE Id classes into single class. o Merged the MESSAGE_ID/MESSAGE_ID_ACK classes into single class. o Removed the MD5 security option. 1. Introduction Optical networks are being developed with photonic switches (PXCs), optical crossconnects (OXCs), routers, switches, DWDM systems, and add-drop multiplexors (ADMs) that use a common control plane [e.g., Generalized MPLS (GMPLS)] to dynamically allocate resources and to provide network survivability using protection and restoration techniques. A pair of nodes (e.g., two PXCs) may be connected by thousands of fibers, and each fiber may be used to transmit multiple wavelengths if DWDM is used. Furthermore, multiple fibers and/or multiple wavelengths may be combined into a single traffic- engineering (TE) link for routing purposes. To enable communication between nodes for routing, signaling, and link management, control channels must be established between the node pair; however, the interface over which the control messages are sent/received may not be the same interface over which the data flows. This draft specifies a link management protocol (LMP) that runs between neighboring nodes and is used to manage TE links. In this draft, OXC is used to refer to all categories of optical crossconnects irrespective of the internal switching fabric. Furthermore, a distinction is made between crossconnects that require opto-electronic conversion, called digital crossconnects (DXCs), and those that are all-optical, called photonic switches or photonic crossconnects (PXCs) û often referred to as pure crossconnects [LAMBDA] because their transparent nature introduces new restrictions for monitoring and managing the data links. LMP can be used for any type of node, enhancing the functionality of traditional DXCs and routers, while enabling PXCs and DWDMs to intelligently interoperate in heterogeneous optical networks. In GMPLS, the control channels between two adjacent nodes are no longer required to use the same physical medium as the data-bearing links between those nodes. For example, a control channel could use a separate wavelength or fiber, an Ethernet link, an IP tunnel through a separate management network, or a multi-hop IP network. A consequence of allowing the control channel(s) between two nodes to be physically diverse from the associated data links is that the health of a control channel does not necessarily correlate to the health of the data links, and vice-versa. Therefore, a clean separation between the fate of the control channel and data-bearing links must be made. New mechanisms must be developed to manage the Lang et al [Page 4]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 data-bearing links, both in terms of link provisioning and fault management. For the purposes of this document, a data-bearing link may be either a "port" or a "component link" depending on its multiplexing capability; component links are multiplex capable, whereas ports are not multiplex capable. This distinction is important since the management of such links (including, for example, resource allocation, label assignment, and their physical verification) is different based on their multiplexing capability. For example, a SONET crossconnect with OC-192 interfaces may be able to demultiplex the OC-192 stream into four OC-48 streams. If multiple interfaces are grouped together into a single TE link using link bundling [BUNDLE], then the link resources must be identified using three levels: TE link Id, component interface Id, and timeslot label. Resource allocation happens at the lowest level (timeslots), but physical connectivity happens at the component link level. As another example, consider the case where a PXC transparently switches OC-192 lightpaths. If multiple interfaces are once again grouped together into a single TE link, then link bundling [BUNDLE] is not required and only two levels of identification are required: TE link Id and port Id. In this case, both resource allocation and physical connectivity happen at the lowest level (i.e. port level). To ensure interworking between data links with different multiplexing capabilities, LMP capable devices SHOULD allow sub- channels of a component link to be locally configured as (logical) data links. For example, if a Router with 4 OC-48 interfaces is connected through a 4:1 MUX to an OXC with OC-192c interfaces, the OXC SHOULD be able to configure each OC-48 sub-channel as a data link. LMP is designed to support aggregation of one or more data-bearing links into a TE link (either ports into TE links, or component links into TE links). The purpose of forming a TE link is to group/map the information about certain physical resources (and their properties) into the information that is used by Constrained SPF for the purpose of path computation, and by GMPLS signaling. 2. LMP Overview The two core procedures of LMP are control channel management and link property correlation. Control channel management is used to establish and maintain control channels between adjacent nodes. This is done using a Config message exchange and a fast keep-alive mechanism between the nodes. The latter is required if lower-level mechanisms are not available to detect control channel failures. Link property correlation is used to synchronize the TE link properties and verify the TE link configuration. LMP requires that a pair of nodes have at least one active bi- directional control channel between them. Each direction of the Lang et al [Page 5]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 control channel is identified by a control channel id (CCId), and the two directions are coupled together using the LMP Config message exchange. All LMP messages are IP encoded [except in some cases, the Test Message which may be limited by the transport mechanism for in- band messaging]. The link level encoding of the control channel is outside the scope of this document. An "LMP adjacency" is formed between two nodes when at least one bi- directional control channel is established between them. Multiple control channels may be active simultaneously for each adjacency; control channel parameters, however, MUST be individually negotiated for each control channel. If the LMP fast keep-alive is used over a control channel, LMP Hello messages MUST be exchanged over the control channel. Other LMP messages MAY be transmitted over any of the active control channels between a pair of adjacent nodes. One or more active control channels may be grouped into a logical control channel for signaling, routing, and link property correlation purposes. The link property correlation function of LMP is designed to aggregate multiple data links (ports or component links) into a TE link and to synchronize the properties of the TE link. As part of the link property correlation function, a LinkSummary message exchange is defined. The LinkSummary message includes the local and remote TE Link Ids, a list of all data links that comprise the TE link, and various link properties. A LinkSummaryAck or LinkSummaryNack message MUST be sent in response to the receipt of a LinkSummary message indicating agreement or disagreement on the link properties. LMP messages are transmitted reliably using Message Ids and retransmissions. Message Ids are carried in MESSAGE_ID objects. No more than one MESSAGE_ID object may be included in an LMP message. For control channel specific messages, the Message Id is within the scope of the control channel over which the message is sent. For TE link specific messages, the Message Id is within the scope of the LMP adjacency. The value of the Message Id is monotonically increasing and only decreases when the value wraps. In this draft, two additional LMP procedures are defined: link connectivity verification and fault management. These procedures are particularly useful when the control channels are physically diverse from the data-bearing links. Link connectivity verification is used for data plane discovery, Interface Id exchange (Interface Ids are used in GMPLS signaling, either as Port labels or Component Interface Ids, depending on the configuration), and physical connectivity verification. This is done by sending Test messages in- band over the data-bearing links and TestStatus messages back over the control channel. Note that the Test message is the only LMP message that must be transmitted over the data-bearing link. The ChannelStatus message exchange is used between adjacent nodes for Lang et al [Page 6]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 both the suppression of downstream alarms and the localization of faults for protection and restoration. For LMP link connectivity verification using a PXC, the Test message is generated and terminated by opaque test units that may be shared among multiple ports. Opaque test units are needed since the PXC ports are transparent. The LMP link connectivity verification procedure is coordinated using a BeginVerify message exchange over a control channel. To support various degrees of transparency (e.g., examining overhead bytes, terminating the payload, etc.), and hence, different mechanisms to transport the Test messages, a Verify Transport Mechanism is included in the BeginVerify and BeginVerifyAck messages. Note that there is no requirement that all data-bearing links must be terminated simultaneously, but at a minimum, it must be possible to terminate them one at a time. There is also no requirement that the control channel and TE link use the same physical medium; however, the control channel MUST terminate on the same two nodes that the TE link spans. Since the BeginVerify message exchange coordinates the Test procedure, it also naturally coordinates the transition of the data links between opaque and transparent mode. The LMP fault management procedure is based on a ChannelStatus exchange using the following messages: ChannelStatus, ChannelStatusAck, ChannelStatusRequest, and ChannelStatusResponse. The ChannelStatus message is sent unsolicitated and is used to notify an LMP neighbor about the status of one or more data channels of a TE link. The ChannelStatusAck message is used to acknowledge receipt of the ChannelStatus message. The ChannelStatusRequest message is used to query an LMP neighbor for the status of one or more data channels of a TE Link. The ChannelStatusResponse message is used to acknowledge receipt of the ChannelStatusRequest message and indicate the states of the queried data links. 3. Control Channel Management To initiate an LMP adjacency between two nodes, one or more bi- directional control channels MUST be activated. The control channels can be used to exchange control-plane information such as link provisioning and fault management information (implemented using a messaging protocol such as LMP, proposed in this draft), path management and label distribution information (implemented using a signaling protocol such as RSVP-TE [RFC3209] or CR-LDP [RFC3219]), and network topology and state distribution information (implemented using traffic engineering extensions of protocols such as OSPF [OSPF-TE] and IS-IS [ISIS-TE]). For the purposes of LMP, the exact implementation of the control channel is not specified; it could be, for example, a separate wavelength or fiber, an Ethernet link, an IP tunnel through a separate management network, or the overhead bytes of a data-bearing link. Rather, a node-wide unique 32-bit non-zero integer control Lang et al [Page 7]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 channel identifier (CCId) is assigned at each end of the control channel. This identifier comes from the same space as the unnumbered interface Id. Furthermore, LMP packets are run over UDP with an LMP port number. Thus, the link level encoding of the control channel is not part of the LMP specification. To establish a control channel, the destination IP address on the far end of the control channel must be known. This knowledge may be manually configured or automatically discovered. Note that for in- band signaling, a control channel could be explicitly configured on a particular data-bearing link. In this case, the Config message exchange can be used to dynamically learn the IP address on the far end of the control channel. This is done by sending the Config message to the Multicast address (224.0.0.1). The ConfigAck and ConfigNack messages MUST be sent to the source IP address found in the IP header of the received Config message. Control channels exist independently of TE links and multiple control channels may be active simultaneously between a pair of nodes. Individual control channels can be realized in different ways; one might be implemented in-fiber while another one may be implemented out-of-fiber. As such, control channel parameters MUST be negotiated over each individual control channel, and LMP Hello packets MUST be exchanged over each control channel to maintain LMP connectivity if other mechanisms are not available. Since control channels are electrically terminated at each node, it may be possible to detect control channel failures using lower layers (e.g., SONET/SDH). There are four LMP messages that are used to manage individual control channels. They are the Config, ConfigAck, ConfigNack, and Hello messages. These messages MUST be transmitted on the channel to which they refer. All other LMP messages may be transmitted over any of the active control channels between a pair of LMP adjacent nodes. In order to maintain an LMP adjacency, it is necessary to have at least one active control channel between a pair of adjacent nodes (recall that multiple control channels can be active simultaneously between a pair of nodes). In the event of a control channel failure, alternate active control channels can be used and it may be possible to activate additional control channels as described below. 3.1. Parameter Negotiation Control channel activation begins with a parameter negotiation exchange using Config, ConfigAck, and ConfigNack messages. The contents of these messages are built using LMP objects, which can be either negotiable or non-negotiable (identified by the N bit in the object header). Negotiable objects can be used to let LMP peers agree on certain values. Non-negotiable objects are used for the announcement of specific values that do not need, or do not allow, negotiation. Lang et al [Page 8]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 To activate a control channel, a Config message MUST be transmitted to the remote node, and in response, a ConfigAck message MUST be received at the local node. The Config message contains the Local Control Channel ID (CC_ID), the senderÆs Node ID, a MessageId for reliable messaging, and a CONFIG object. It is possible that both the local and remote nodes initiate the configuration procedure at the same time. To avoid ambiguities, the node with the higher Node Id wins the contention; the node with the lower Node Id MUST stop transmitting the Config message and respond to the Config message it received. The ConfigAck message is used to acknowledge receipt of the Config message and express agreement on ALL of the configured parameters (both negotiable and non-negotiable). The ConfigNack message is used to acknowledge receipt of the Config message, indicate which (if any) non-negotiable CONFIG objects are unacceptable, and propose alternate values for the negotiable parameters. If a node receives a ConfigNack message with acceptable alternate values for negotiable parameters, the node SHOULD transmit a Config message using these values for those parameters. If a node receives a ConfigNack message with unacceptable alternate values, the node MAY continue to retransmit Config messages. Note that the problem may be solved by an operator changing parameters. In the case where multiple control channels use the same physical interface, the parameter negotiation exchange is performed for each control channel. The various LMP parameter negotiation messages are associated with their corresponding control channels by their node- wide unique identifiers (CCIds). 3.2. Hello Protocol Once a control channel is activated between two adjacent nodes, the LMP Hello protocol can be used to maintain control channel connectivity between the nodes and to detect control channel failures. The LMP Hello protocol is intended to be a lightweight keep-alive mechanism that will react to control channel failures rapidly so that IGP Hellos are not lost and the associated link- state adjacencies are not removed unnecessarily. 3.2.1. Hello Parameter Negotiation Before sending Hello messages, the HelloInterval and HelloDeadInterval parameters MUST be agreed upon by the local and remote nodes. These parameters are exchanged in the Config message. The HelloInterval indicates how frequently LMP Hello messages will be sent, and is measured in milliseconds (ms). For example, if the Lang et al [Page 9]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 value were 150, then the transmitting node would send the Hello message at least every 150ms. The HelloDeadInterval indicates how long a device should wait to receive a Hello message before declaring a control channel dead, and is measured in milliseconds (ms). The HelloDeadInterval MUST be greater than the HelloInterval, and SHOULD be at least 3 times the value of HelloInterval. Suggested default values for the HelloInterval is 5 ms and for the HelloDeadInterval is 18 ms. If the fast keep-alive mechanism of LMP is not used, the HelloInterval and HelloDeadInterval parameters MUST be set to zero. When a node has either sent or received a ConfigAck message, it may begin sending Hello messages. Once it has sent a Hello message and received a valid Hello message (i.e., with expected sequence numbers; see Section 3.2.2), the control channel moves to the UP state. (It is also possible to move to the UP state without sending Hellos if other methods are used to indicate bi-directional control- channel connectivity.) If, however, a node receives a ConfigNack message instead of a ConfigAck message, the node MUST not send Hello messages and the control channel SHOULD NOT move to the UP state. See Section 12.1 for the complete control channel FSM. 3.2.2. Fast Keep-alive Each Hello message contains two sequence numbers: the first sequence number (TxSeqNum) is the sequence number for the Hello message being sent and the second sequence number (RcvSeqNum) is the sequence number of the last Hello message received from the adjacent node over this control channel. Each node increments its sequence number when it sees its current sequence number reflected in Hellos received from its peer. The sequence numbers start at 1 and wrap around back to 2; 0 is used in the RcvSeqNum to indicate that a Hello has not yet been seen. Under normal operation, the difference between the RcvSeqNum in a Hello message that is received and the local TxSeqNum that is generated will be at most 1. This difference can be more than one only when a control channel restarts or when the values wrap. Note that the 32-bit sequence numbers MAY wrap. The following expression may be used to test if a newly received TxSeqNum value is less than a previously received value: If ((int) old_id û (int) new_id > 0) { New value is less than old value; } Having sequence numbers in the Hello messages allows each node to verify that its peer is receiving its Hello messages. By including Lang et al [Page 10]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 the RcvSeqNum in Hello packets, the local node will know which Hello packets the remote node has received. The following example illustrates how the sequence numbers operate. Note that only the operation at one node is shown, and alternative scenarios are possible: 1) After completing the configuration stage, Node A sends Hello messages to Node B with {TxSeqNum=1;RcvSeqNum=0}. 2) When Node A receives a Hello from Node B with {TxSeqNum=1;RcvSeqNum=1}, it sends Hellos to Node B with {TxSeqNum=2;RcvSeqNum=1}. 3) When Node A receives a Hello from Node B with {TxSeqNum=2;RcvSeqNum=2}, it sends Hellos to Node B with {TxSeqNum=3;RcvSeqNum=2}. 3.2.3. Control Channel Down To allow bringing a control channel DOWN gracefully for administration purposes, a ControlChannelDown flag is available in the Common Header of LMP packets. When data links are still in use between a pair of nodes, a control channel SHOULD only be taken down administratively when there are other active control channels that can be used to manage the data links. When bringing a control channel DOWN administratively, a node MUST set the ControlChannelDown flag in all LMP messages sent over the control channel. The node that initiated the control channel DOWN procedure may stop sending Hello messages after HelloDeadInterval seconds have passed, or if it receives an LMP message over the same control channel with the ControlChannelDown flag set. When a node receives an LMP packet with the ControlChannelDown flag set, it SHOULD send a Hello message with the ControlChannelDown flag set and move the control channel to the Down state. 3.2.4. Degraded State A consequence of allowing the control channels to be physically diverse from the associated data links is that there may not be any active control channels available while the data links are still in use. For many applications, it is unacceptable to tear down a link that is carrying user traffic simply because the control channel is no longer available; however, the traffic that is using the data links may no longer be guaranteed the same level of service. Hence the TE link is in a Degraded state. When a TE link is in the Degraded state, routing and signaling SHOULD be notified so that new connections are not accepted and the TE link is advertised with no unreserved resources. 4. Link Property Correlation Lang et al [Page 11]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 As part of LMP, a link property correlation exchange is defined for TE links using the LinkSummary, LinkSummaryAck, and LinkSummaryNack messages. The contents of these messages are built using LMP objects, which can be either negotiable or non-negotiable (identified by the N flag in the object header). Negotiable objects can be used to let both sides agree on certain link parameters. Non- negotiable objects are used for announcement of specific values that do not need, or do not allow, negotiation. Each TE link has an identifier (Link_Id) that is assigned at each end of the link. These identifiers MUST be the same type (i.e, IPv4, IPv6, unnumbered) at both ends. If a LinkSummary message is received with different local and remote TE link types, then a LinkSummaryNack message MUST be sent with Error Code "Bad TE Link Object". Similarly, each data link is assigned an identifier (Interface_Id) at each end. These identifiers MUST also be the same type at both ends. If a LinkSummary message is received with different local and remote Interface Id types then a LinkSummaryNack message MUST be sent with Error Code "Bad Data Link Object". Link property correlation SHOULD be done before the link is brought up and MAY be done at any time a link is UP and not in the Verification process. The LinkSummary message is used to verify for consistency the TE and data bearing link information on both sides. Link Summary messages are also used to aggregate multiple data links (either ports or component links) into a TE link; exchange, correlate (to determine inconsistencies), or change TE link parameters; and exchange, correlate (to determine inconsistencies), or change Interface Ids (used either Port Ids or Component Interface Ids). The LinkSummary message includes a TE_LINK object followed by one or more DATA_LINK objects. The TE_LINK object identifies the TE link's local and remote Link Id and indicates support for fault management and link verification procedures for that TE link. The DATA_LINK objects are used to characterize the data links that comprise the TE link. These objects include the local and remote Interface Ids, and may include one or more sub-objects further describing the properties of the data links. If the LinkSummary message is received from a remote node and the Interface Id mappings match those that are stored locally, then the two nodes have agreement on the Verification procedure (see Section 5) and data link configuration. If the verification procedure is not used, the LinkSummary message can be used to verify agreement on manual configuration. The LinkSummaryAck message is used to signal agreement on the Interface Id mappings and link property definitions. Otherwise, a LinkSummaryNack message MUST be transmitted, indicating which Lang et al [Page 12]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 Interface mappings are not correct and/or which link properties are not accepted. If a LinkSummaryNack message indicates that the Interface Id mappings are not correct and the link verification procedure is enabled, the link verification process SHOULD be repeated for all mismatched free data links; if an allocated data link has a mapping mismatch, it SHOULD be flagged and verified when it becomes free. If a LinkSummaryNack message includes negotiable parameters, then acceptable values for those parameters MUST be included. If a LinkSummaryNack message is received and includes negotiable parameters, then the initiator of the LinkSummary message SHOULD send a new LinkSummary message. The new LinkSummary message SHOULD include new values for the negotiable parameters. These values SHOULD take into account the acceptable values received in the LinkSummaryNack message. It is possible that the LinkSummary message could grow quite large due to the number of DATA LINK objects. Since the LinkSummary message is IP encoded, normal IP fragmentation should be used if the resulting PDU exceeds the MTU. 5. Verifying Link Connectivity In this section, an optional procedure is described that may be used to verify the physical connectivity of the data-bearing links and dynamically learn (i.e., discover) the TE link and Interface ID associations. The procedure SHOULD be done when establishing a TE link, and subsequently, on a periodic basis for all unallocated (free) data links of the TE link. Support for this procedure is indicated by setting the "Link Verification Supported" flag in the TE_LINK object of the LinkSummary message. If a BeginVerify message is received and link verification is not supported for the TE link, then a BeginVerifyNack message MUST be transmitted with Error Code indicating "Link Verification Procedure not supported for this TE Link." A unique characteristic of all-optical switches is that the data- bearing links are transparent when allocated to user traffic. This characteristic poses a challenge for validating the connectivity of the data links. For example, shining unmodulated light through a link may not result in received light at the next switch because there may be terminating (or opaque) elements, such as DWDM equipment, between the PXCs. Therefore, to ensure proper verification of data link connectivity, it is required that until the links are allocated for user traffic, they must be opaque. To support various degrees of opaqueness (e.g., examining overhead bytes, terminating the payload, etc.), and hence different mechanisms to transport the Test messages, a Verify Transport Mechanism field is included in the BeginVerify and BeginVerifyAck messages. Lang et al [Page 13]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 There is no requirement that all data links be terminated simultaneously, but at a minimum, the data links MUST be able to be terminated one at a time. Furthermore, for the link verification procedure it is assumed that the nodal architecture is designed so that messages can be sent and received over any data link. Note that this requirement is trivial for DXCs (and OEO devices in general) since each data link is terminated and processed electronically before being forwarded to the next OEO device, but that in PXCs (and transparent devices in general) this is an additional requirement. To interconnect two nodes, a TE link is defined between them, and at a minimum, there MUST be at least one active control channel between the nodes. For link verification, a TE link MUST include at least one data link. Once a control channel has been established between the two nodes, data link connectivity can be verified by exchanging Test messages over each of the data links specified in the TE link. It should be noted that all LMP messages except the Test message are exchanged over the control channels and that Hello messages continue to be exchanged over each control channel during the data link verification process. The Test message is sent over the data link that is being verified. Data links are tested in the transmit direction as they are unidirectional, and therefore, it may be possible for both nodes to (independently) exchange the Test messages simultaneously. To initiate the link verification procedure, the local node MUST send a BeginVerify message over a control channel. To limit the scope of Link Verification to a particular TE Link, the LOCAL_LINK_ID MUST be non-zero. If this field is zero, the data links can span multiple TE links and/or they may comprise a TE link that is yet to be configured. For the case where the LOCAL_LINK_ID field is zero, the "Verify all Links" flag of the BEGIN_VERIFY object is used to distinguish between data links that span multiple TE links and those that have not yet been assigned to a TE link. Specifically, verification of data links that span multiple TE links is indicated by setting the LOCAL_LINK_ID field to zero and setting the "Verify all Links" flag. Verification of data links that have not yet been assigned to a TE link is indicated by setting the LOCAL_LINK_ID field to zero and clearing the "Verify all Links" flag. The BeginVerify message also contains the number of data links that are to be verified; the interval (called VerifyInterval) at which the Test messages will be sent; the encoding scheme and transport mechanisms that are supported; the data rate for Test messages; and, when the data links correspond to fibers, the wavelength identifier over which the Test messages will be transmitted. Lang et al [Page 14]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 If the remote node receives a BeginVerify message and it is ready to process Test messages, it MUST send a BeginVerifyAck message back to the local node specifying the desired transport mechanism for the TEST messages. The remote node includes a 32-bit node unique VerifyId in the BeginVerifyAck message. The VerifyId is then used in all corresponding verification messages to differentiate them from different LMP peers and/or parallel Test procedures. When the local node receives a BeginVerifyAck message from the remote node, it may begin testing the data links by transmitting periodic Test messages over each data link. The Test message includes the VerifyId and the local Interface Id for the associated data link. The remote node MUST send either a TestStatusSuccess or a TestStatusFailure message in response for each data link. A TestStatusAck message MUST be sent to confirm receipt of the TestStatusSuccess and TestStatusFailure messages. It is also permissible for the sender to terminate the Test procedure anytime after sending the BeginVerify message. An EndVerify message SHOULD be sent for this purpose. Message correlation is done using message identifiers and the Verify Id; this enables verification of data links, belonging to different link bundles or LMP sessions, in parallel. When the Test message is received, the received Interface Id (used in GMPLS as either a Port/Wavelength label or Component Interface Identifier depending on the configuration) is recorded and mapped to the local Interface Id for that data link, and a TestStatusSuccess message MUST be sent. The TestStatusSuccess message includes the local Interface Id and the remote Interface Id (received in the Test message), along with the VerifyId received in the Test message. The receipt of a TestStatusSuccess message indicates that the Test message was detected at the remote node and the physical connectivity of the data link has been verified. When the TestStatusSuccess message is received, the local node SHOULD mark the data link as UP and send a TestStatusAck message to the remote node. If, however, the Test message is not detected at the remote node within an observation period (specified by the VerifyDeadInterval), the remote node will send a TestStatusFailure message over the control channel indicating that the verification of the physical connectivity of the data link has failed. When the local node receives a TestStatusFailure message, it SHOULD mark the data link as FAILED and send a TestStatusAck message to the remote node. When all the data links on the list have been tested, the local node SHOULD send an EndVerify message to indicate that testing is complete on this link. If the local/remote data link mappings are known, then the link verification procedure can be optimized by testing the data links in a defined order known to both nodes. The suggested criteria for this ordering is in increasing value of the Remote_Interface_ID. Lang et al [Page 15]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 Both the local and remote nodes SHOULD maintain the complete list of Interface Id mappings for correlation purposes. 5.1. Example of Link Connectivity Verification Figure 1 shows an example of the link verification scenario that is executed when a link between Node A and Node B is added. In this example, the TE link consists of three free ports (each transmitted along a separate fiber) and is associated with a bi-directional control channel (indicated by a "c"). The verification process is as follows: o A sends a BeginVerify message over the control channel to B indicating it will begin verifying the ports that form the TE link. The LOCAL_LINK_ID object carried in the BeginVerify message carries the identifier (IP address or interface index) that A assigns to the link. o Upon receipt of the BeginVerify message, B creates a VerifyId and binds it to the TE Link from A. This binding is used later when B receives the Test messages from A, and these messages carry the VerifyId. B discovers the identifier (IP address or interface index) that A assigns to the TE link by examining the LOCAL_LINK_ID object carried in the received BeginVerify message. (If the data ports are not yet assigned to the TE Link, the binding is limited to the Node Id of A.) In response to the BeginVerify message, B sends to A the BeginVerifyAck message. The LOCAL_LINK_ID object carried in the BeginVerifyAck message is used to carry the identifier (IP address or interface index) that B assigns to the TE link. The REMOTE_LINK_ID object carried in the BeginVerifyAck message is used to bind the TE link Ids assigned by both A and B. The VerifyId is returned to A in the BeginVerifyAck message over the control channel. o When A receives the BeginVerifyAck message, it begins transmitting periodic Test messages over the first port (Interface Id=1). The Test message includes the Interface Id for the port and the VerifyId that was assigned by B. o When B receives the Test messages, it maps the received Interface Id to its own local Interface Id = 10 and transmits a TestStatusSuccess message over the control channel back to PXC A. The TestStatusSuccess message includes both the local and received Interface Ids for the port as well as the VerifyId. The VerifyId is used to determine the local/remote TE link identifiers (IP addresses or interface indices) for which the data links belong. o A will send a TestStatusAck message over the control channel back to B indicating it received the TestStatusSuccess message. o The process is repeated until all of the ports are verified. o At this point, A will send an EndVerify message over the control channel to B to indicate that testing is complete. o B will respond by sending an EndVerifyAck message over the control channel back to A. Lang et al [Page 16]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 Note that this procedure can be used to "discover" the connectivity of the data ports. +---------------------+ +---------------------+ + + + + + PXC A +<-------- c --------->+ PXC B + + + + + + + + + + 1 +--------------------->+ 10 + + + + + + + + + + 2 + /---->+ 11 + + + /----/ + + + + /---/ + + + 3 +----/ + 12 + + + + + + + + + + 4 +--------------------->+ 14 + + + + + +---------------------+ +---------------------+ Figure 1: Example of link connectivity between PXC A and PXC B. 6. Fault Management In this section, an optional LMP procedure is described that is used to manage failures by rapid notification of the status of one or more data channels of a TE Link. The scope of this procedure is within a TE link, and as such, the use of this procedure is negotiated as part of the LinkSummary exchange. The procedure can be used to rapidly isolate link failures and is designed to work for both unidirectional and bi-directional LSPs. An important implication of using PXCs is that traditional methods that are used to monitor the health of allocated data links in OEO nodes (e.g., DXCs) may no longer be appropriate, since PXCs are transparent to the bit-rate, format, and wavelength. Instead, fault detection is delegated to the physical layer (i.e., loss of light or optical monitoring of the data) instead of layer 2 or layer 3. Recall that a TE link connecting two nodes may consist of a number of data links. If one or more data links fail between two nodes, a mechanism must be used for rapid failure notification so that appropriate protection/restoration mechanisms can be initiated. If the failure is subsequently cleared, then a mechanism must be used to notify that the failure is clear and the channel status is OK. 6.1. Fault Detection Fault detection should be handled at the layer closest to the failure; for optical networks, this is the physical (optical) layer. One measure of fault detection at the physical layer is detecting Lang et al [Page 17]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 loss of light (LOL). Other techniques for monitoring optical signals are still being developed and will not be further considered in this document. However, it should be clear that the mechanism used for fault notification in LMP is independent of the mechanism used to detect the failure, but simply relies on the fact that a failure is detected. 6.2. Fault Localization Procedure If data links fail between two PXCs, the power monitoring system in all of the downstream nodes may detect LOL and indicate a failure. To avoid multiple alarms stemming from the same failure, LMP provides a failure notification through the ChannelStatus message. This message may be used to indicate that a single data channel has failed, multiple data channels have failed, or an entire TE link has failed. Failure correlation is done locally at each node upon receipt of the failure notification. To localize a fault to a particular link between adjacent OXCs, a downstream node (downstream in terms of data flow) that detects data link failures will send a ChannelStatus message to its upstream neighbor indicating that a failure has occurred (bundling together the notification of all of the failed data links). An upstream node that receives the ChannelStatus message MUST send a ChannelStatusAck message to the downstream node indicating it has received the ChannelStatus message. The upstream node should correlate the failure to see if the failure is also detected locally (including ingress side) for the corresponding LSP(s). If, for example, the failure is clear on the input of the upstream node or internally, then the upstream node will have localized the failure. Once the failure is correlated, the upstream node SHOULD send a ChannelStatus message to the downstream node indicating that the channel is failed or is ok. If a ChannelStatus message is not received by the downstream node, it SHOULD send a ChannelStatusRequest message for the channel in question. Once the failure has been localized, the signaling protocols may be used to initiate span or path protection and restoration procedures. If all of the data links of a TE link have failed, then the upstream node MAY be notified of the TE link failure without specifying each data link of the failed TE link. This is done by sending failure notification in a ChannelStatus message identifying the TE Link without including the Interface Ids in the CHANNEL_STATUS object. 6.3. Examples of Fault Localization In Fig. 2, a sample network is shown where four nodes are connected in a linear array configuration. The control channels are bi- directional and are labeled with a "c". All LSPs are also bi- directional. Lang et al [Page 18]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 In the first example [see Fig. 2(a)], there is a failure on one direction of the bi-directional LSP. Node 4 will detect the failure and will send a ChannelStatus message to Node 3 indicating the failure (e.g., LOL) to the corresponding upstream node. When Node 3 receives the ChannelStatus message from Node 4, it returns a ChannelStatusAck message back to Node 4 and correlates the failure locally. When Node 3 correlates the failure and verifies that it is CLEAR, it has localized the failure to the data link between Node 3 and Node 4. At that time, Node 3 should send a ChannelStatus message to Node 4 indicating that the failure has been localized. In the second example [see Fig. 2(b)], a single failure (e.g., fiber cut) affects both directions of the bi-directional LSP. Node 2 (Node 3) will detect the failure of the upstream (downstream) direction and send a ChannelStatus message to the upstream (in terms of data flow) node indicating the failure (e.g., LOL). Simultaneously (ignoring propagation delays), Node 1 (Node 4) will detect the failure on the upstream (downstream) direction, and will send a ChannelStatus message to the corresponding upstream (in terms of data flow) node indicating the failure. Node 2 and Node 3 will have localized the two directions of the failure. +-------+ +-------+ +-------+ +-------+ + Node1 + + Node2 + + Node3 + + Node4 + + +-- c ---+ +-- c ---+ +-- c ---+ + ----+---\ + + + + + + + <---+---\\--+--------+-------+---\ + + + /--+---> + \--+--------+-------+---\\---+-------+---##---+---//--+---- + + + + \---+-------+--------+---/ + + + + + + + (a) + + ----+-------+--------+---\ + + + + + <---+-------+--------+---\\--+---##---+--\ + + + + + + \--+---##---+--\\ + + + + + + + (b) + \\--+--------+-------+---> + + + + + \--+--------+-------+---- + + + + + + + + +-------+ +-------+ +-------+ +-------+ Figure 2: Two types of data link failures are shown (indicated by ## in the figure): (A) a data link corresponding to the downstream direction of a bi-directional LSP fails, (B) two data links corresponding to both directions of a bi-directional LSP fail. The control channel connecting two nodes is indicated with a "c". 6.4. Channel Activation Indication The ChannelStatus message may also be used to notify an LMP neighbor that the data link should be actively monitored. This is called Channel Activation Indication. This is particularly useful in networks with transparent nodes where the status of data links may Lang et al [Page 19]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 need to be triggered using control channel messages. For example, if a data link is pre-provisioned and the physical link fails after verification and before inserting user traffic, a mechanism is needed to indicate the data link should be active or the failure may not be able to be detected. The ChannelStatus message is used to indicate that a channel or group of channels are now active. The ChannelStatusAck message MUST be transmitted upon receipt of a ChannelStatus message. When a ChannelStatus message is received, the corresponding data link(s) MUST be put into the Active state. If upon putting them into the Active state, a failure is detected, the ChannelStatus message SHOULD be transmitted as described in Section 6.2. 6.5. Channel Deactivation Indication The ChannelStatus message may also be used to notify an LMP neighbor that the data link no longer needs to be actively monitored. This is the counterpart to the Channel Active Indication. When a ChannelStatus message is received with Channel Deactive Indication, the corresponding data link(s) MUST be taken out of the Active state. 7. Message_Id Usage The MESSAGE_ID and MESSAGE_ID_ACK objects are included in LMP messages to support reliable message delivery. This section describes the usage of these objects. The MESSAGE_ID and MESSAGE_ID_ACK objects contain a Message_Id field. Only one MESSAGE_ID/MESSAGE_ID_ACK object may be included in any LMP message. For control channel specific messages, the Message_Id field is within the scope of the CCID. For TE link specific messages, the Message_Id field is within the scope of the LMP adjacency. The Message_Id field of the MESSAGE_ID object contains a generator selected value. This value MUST be monotonically increasing. A value is considered to be previously used when it has been sent in an LMP message with the same CCID (for control channel specific messages) or LMP adjacency (for TE Link specific messages). The Message_Id field of the MESSAGE_ID_ACK object contains the Message_Id field of the message being acknowledged. Unacknowledged messages sent with the MESSAGE_ID object SHOULD be retransmitted until the message is acknowledged or until a retry limit is reached (see also Section 10). Note that the 32-bit Message_Id value MAY wrap. The following expression may be used to test if a newly received Message_Id value is less than a previously received value: Lang et al [Page 20]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 If ((int) old_id û (int) new_id > 0) { New value is less than old value; } Nodes processing incoming messages SHOULD check to see if a newly received message is out of order and can be ignored. Out-of-order messages can be identified by examining the value in the Message_Id field. If the message is a Config message, and the Message_Id value is less than the largest Message_Id value previously received from the sender for the CCID, then the message SHOULD be treated as being out of order. If the message is a LinkSummary message and the Message_Id value is less than the largest Message_Id value previously received from the sender for the TE Link, then the message SHOULD be treated as being out of order. If the message is a ChannelStatus message and the Message_Id value is less than the largest Message_Id value previously received from the sender for the specified TE link, then the receiver SHOULD check the Message_Id value previously received for the state of each data channel included in the ChannelStatus message. If the Message_Id value is greater than the most recently received Message_Id value associated with at least one of the data channels included in the message, the message MUST NOT be treated as out of order; otherwise the message SHOULD be treated as being out of order. However, the state of any data channel MUST NOT be updated if the Message_Id value is less than the most recently received Message_Id value associated with the data channel. All other messages MUST NOT be treated as out-of-order. 8. Graceful Restart This section describes the mechanism to resynchronize the LMP state after a control plane restart. A control plane restart may occur when bringing up the first control channel after an LMP adjacency has failed, or as a result of an LMP component restart. The latter is detected by setting the "LMP Restart" bit in the Common Header of the LMP messages. When the control plane fails due to the loss of the control channel (rather than an LMP component restart), the LMP Link information should be retained. It is possible that a node may be capable of retaining the LMP Link information across an LMP component restart. However, in both cases the status of the data channels MUST be synchronized. It is assumed the Local Interface Ids remain stable across a control plane restart. Lang et al [Page 21]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 After the control plane of a node restarts, the control channel(s) must be re-established using the procedures of Section 3.1. If the control plane failure was the result of an LMP component restart, then the "LMP Restart" flag MUST be set in LMP messages until a Hello message is received with the RcvSeqNum equal to the local TxSeqNum. This indicates that the control channel is UP and the LMP neighbor has detected the restart. The following assumes that the LMP component restart only occurred on one end of the TE Link. If the LMP component restart occurred on both ends of the TE Link, the normal procedures for LinkSummary should be used, as described in Section 4. Once a control channel is UP, the LMP neighbor MUST send a LinkSummary message for each TE Link across the adjacency. All the objects of the LinkSummary message MUST have the N-bit set to 0 indicating that the parameters are non-negotiable. This provides the local/remote Link Id and Interace Id mappings, the associated Link/Data channel parameters, and indication of which data links are currently allocated to user traffic. When a node receives the LinkSummary message, it checks its local configuration. If the node is capable of retaining the LMP Link information across a restart, it must process the LinkSummary message as described in Section 4 with the exception that the allocated/deallocated flag of the DATA_LINK object received in the LinkSummary message MUST take precedence over any local value. If, however, the node was not capable of retaining the LMP Link information across a restart, the node MUST accept the Link/Data channel parameters of the received LinkSummary message and respond with a LinkSummaryAck message. Upon completion of the LinkSummary exchange, the node that has restarted the control plane SHOULD send a ChannelStatusRequest message for that TE link. The node SHOULD also verify the connectivity of all unallocated data channels. 9. Addressing All LMP messages are sent directly over IP (except, in some cases, the Test messages are limited by the transport mechanism for in-band messaging). The destination address of the IP packet MAY be either the address learned in the Configuration procedure (i.e., the Source IP address found in the IP header of the received Config message), an IP address configured on the remote node, or the node ID. The Config message is an exception as described below. The manner in which a Config message is addressed may depend on the signaling transport mechanism. When the transport mechanism is a point-to-point link, Config messages SHOULD be sent to the Multicast address (224.0.0.1). Otherwise, Config messages MUST be sent to an IP address on the neighboring node. This may be configured at both ends of the control channel or may be automatically discovered. Lang et al [Page 22]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 10. Exponential Back-off Procedures This section is based on [RFC2961] and provides exponential backup procedures for message retransmission. Implementations MUST use the described procedures or their equivalent. 10.1. Operation The following operation is one possible mechanism for exponential back-off retransmission of unacknowledged LMP messages. The sending node retransmits the message until an acknowledgement message is received or until a retry limit is reached. When the sending node receives the acknowledgement, retransmission of the message is stopped. The interval between message retransmission is governed by a rapid retransmission timer. The rapid retransmission timer starts at a small interval and increases exponentially until it reaches a threshold. The following time parameters are useful to characterize the procedures: Rapid retransmission interval Ri: Ri is the initial retransmission interval for unacknowledged messages. After sending the message for the first time, the sending node will schedule a retransmission after Ri milliseconds. Rapid retry limit Rl: Rl is the maximum number of times a message will be transmitted without being acknowledged. Increment value Delta: Delta governs the speed with which the sender increases the retransmission interval. The ratio of two successive retransmission intervals is (1 + Delta). Suggested default values for an initial retransmission interval (Ri) of 500ms, a power of 2 exponential back-off (Delta = 1) and a retry limit of 3. 10.2. Retransmission Algorithm After a node transmits a message requiring acknowledgement, it should immediately schedule a retransmission after Ri seconds. If a corresponding acknowledgement message is received before Ri seconds, then message retransmission SHOULD be canceled. Otherwise, it will retransmit the message after (1+Delta)*Ri seconds. The retransmission will continue until either an appropriate Lang et al [Page 23]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 acknowledgement message is received or the rapid retry limit, Rl, has been reached. A sending node can use the following algorithm when transmitting a message that requires acknowledgement: Prior to initial transmission, initialize Rk = Ri and Rn = 0. while (Rn++ < Rl) { transmit the message; wake up after Rk milliseconds; Rk = Rk * (1 + Delta); } /* acknowledged message or no reply from receiver and Rl reached*/ do any needed clean up; exit; Asynchronously, when a sending node receives a corresponding acknowledgment message, it will change the retry count, Rn, to Rl. Note that the transmitting node does not advertise or negotiate the use of the described exponential back-off procedures in the Config or LinkSummary messages. 11. IANA Considerations LMP defines the following name spaces that require management: - Msg Type Name Space. - LMP Object Class name space. - LMP Object Class type (C-Type). These are unique within the Object Class. Following the policies outlined in [IANA], Msg Type, Object Class, and Class type are allocated through an IETF Consensus action. 12. LMP Finite State Machines 12.1. Control Channel FSM The control channel FSM defines the states and logics of operation of an LMP control channel. The description of FSM state transitions and associated actions is given in Section 3. 12.1.1. Control Channel States A control channel can be in one of the states described below. Every state corresponds to a certain condition of the control channel and is usually associated with a specific type of LMP message that is periodically transmitted to the far end. Lang et al [Page 24]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 Down: This is the initial control channel state. In this state, no attempt is being made to bring the control channel up and no LMP messages are sent. The control channel parameters should be set to the initial values. ConfigSnd: The control channel is in the parameter negotiation state. In this state the node periodically sends a Config message, and is expecting the other side to reply with either a ConfigAck or ConfigNack message. The FSM does not transition into the Active state until the remote side positively acknowledges the parameters. ConfRcv: The control channel is in the parameter negotiation state. In this state, the node is waiting for acceptable configuration parameters from the remote side. Once such parameters are received and acknowledged, the FSM can transition to the Active state. Active: In this state the node periodically sends a Hello message and is waiting to receive a valid Hello message. Once a valid Hello message is received, it can transition to the UP state. Up: The CC is in an operational state. The node receives valid Hello messages and sends Hello messages. GoingDown: A CC may go into this state because of administrative action. While a CC is in this state, the node sets the ControlChannelDown bit in all the messages it sends. 12.1.2. Control Channel Events Operation of the LMP control channel is described in terms of FSM states and events. Control channel Events are generated by the underlying protocols and software modules, as well as by the packet processing routines and FSMs of associated TE links. Every event has its number and a symbolic name. Description of possible control channel events is given below. 1 : evBringUp: This is an externally triggered event indicating that the control channel negotiation should begin. This event, for example, may be triggered by an operator command, by the successful completion of a control channel bootstrap procedure, or by configuration. Depending on the configuration, this will trigger either 1a) the sending of a Config message, 1b) a period of waiting to receive a Config message from the remote node. Lang et al [Page 25]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 2 : evCCDn: This event is generated when there is indication that the control channel is no longer available. 3 : evConfDone: This event indicates a ConfigAck message has been received, acknowledging the Config parameters. 4 : evConfErr: This event indicates a ConfigNack message has been received, rejecting the Config parameters. 5 : evNewConfOK: New Config message was received from neighbor and positively Acknowledged. 6 : evNewConfErr: New Config message was received from neighbor and rejected with a ConfigNack message. 7 : evContenWin: New Config message was received from neighbor at the same time a Config message was sent to the neighbor. The Local node wins the contention. As a result, the received Config message is ignored. 8 : evContenLost: New Config message was received from neighbor at the same time a Config message was sent to the neighbor. The Local node loses the contention. 8a) The Config message is positively Acknowledged. 8b) The Config message is negatively Acknowledged. 9 : evAdminDown: The administrator has requested that the control channel is brought down administratively. Hello messages (with ControlChannelDown flag set) SHOULD be sent for HelloDeadInterval seconds or until an LMP message is received over the control channel with the ControlChannelDown flag set. 10: evNbrGoesDn: A packet with ControlChannelDown flag is received from the neighbor. 11: evHelloRcvd: A Hello packet with expected SeqNum has been received. 12: evHoldTimer: The HelloDeadInterval timer has expired indicating that no Hello packet has been received. This moves the control channel back into the Negotiation state, and depending on the local configuration, this will trigger either 12a) the sending of periodic Config messages, 12b) a period of waiting to receive Config messages from the remote node. 13: evSeqNumErr: A Hello with unexpected SeqNum received and discarded. Lang et al [Page 26]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 14: evReconfig: Control channel parameters have been reconfigured and require renegotiation. 15: evConfRet: A retransmission timer has expired and a Config message is resent. 16: evHelloRet: The HelloInterval timer has expired and a Hello packet is sent. 17: evDownTimer: A timer has expired and no messages have been received with the ControlChannelDown flag set. Lang et al [Page 27]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 12.1.3. Control Channel FSM Description Figure 3 illustrates operation of the control channel FSM in a form of FSM state transition diagram. +--------+ +----------------->| |<--------------+ | +--------->| Down |<----------+ | | |+---------| |<-------+ | | | || +--------+ | | | | || | ^ 2,9| 2| 2| | ||1b 1a| | | | | | || v |2,9 | | | | || +--------+ | | | | || +->| |<------+| | | | || 4,7,| |ConfSnd | || | | | || 14,15+--| |<----+ || | | | || +--------+ | || | | | || 3,8a| | | || | | | || +---------+ |8b 14,12a| || | | | || | v | || | | | |+-|------>+--------+ | || | | | | | +->| |-----|-|+ | | | | |6,14| |ConfRcv | | | | | | | | +--| |<--+ | | | | | | | +--------+ | | | | | | | | 5| ^ | | | | | | | +---------+ | | | | | | | | | | | | | | | | | | | v v |6,12b | | | | | | |10 +--------+ | | | | | | +----------| | | | | | | | | +--| Active |---|-+ | | | 10,17| | 5,16| | |-------|---+ | +-------+ 9 | 13 +->| | | | | | Going |<--|----------+--------+ | | | | Down | | 11| ^ | | | +-------+ | | |5 | | | ^ | v | 6,12b| | | |9 |10 +--------+ | |12a,14 | | +----------| |---+ | | | | Up |-------+ | +------------------| |---------------+ +--------+ | ^ | | +---+ 11,13,16 Figure 3: Control Channel FSM Lang et al [Page 28]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 Event evCCDn always forces the FSM to the Down State. Events evHoldTimer evReconfig always force the FSM to the Negotiation state (either ConfigSnd or ConfigRcv). 12.2. TE Link FSM The TE Link FSM defines the states and logics of operation of an LMP TE Link. 12.2.1. TE Link States An LMP TE link can be in one of the states described below. Every state corresponds to a certain condition of the TE link and is usually associated with a specific type of LMP message that is periodically transmitted to the far end via the associated control channel or in-band via the data links. Down: There are no data links allocated to the TE link. Init: Data links have been allocated to the TE link, but the configuration has not yet been synchronized with the LMP neighbor. Up: This is the normal operational state of the TE link. At least one primary CC is required to be operational between the nodes sharing the TE link. Degraded: In this state, all primary CCs are down, but the TE link still includes some data links that are allocated to data traffic. 12.2.2. TE Link Events Operation of the LMP TE link is described in terms of FSM states and events. TE Link events are generated by the packet processing routines and by the FSMs of the associated primary control channel(s) and the data links. Every event has its number and a symbolic name. Description of possible control channel events is given below. 1 : evDCUp: One or more data channels have been enabled and assigned to the TE Link. 2 : evSumAck: LinkSummary message received and positively acknowledged. 3 : evSumNack: LinkSummary message received and negatively acknowledged. 4 : evRcvAck: LinkSummaryAck message received acknowledging the TE Link Configuration. 5 : evRcvNack: LinkSummaryNack message received. 6 : evSumRet: Retransmission timer has expired and LinkSummary message is resent. 7 : evCCUp: First active control channel goes up. Lang et al [Page 29]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 8 : evCCDown: Last active control channel goes down. 9 : evDCDown: Last data channel of TE Link has been removed. 12.2.3. TE Link FSM Description Figure 4 illustrates operation of the LMP TE Link FSM in a form of FSM state transition diagram. 3,7,8 +--+ | | | v +--------+ | | +------------>| Down |<---------+ | | | | | +--------+ | | | ^ | | 1| |9 | | v | | | +--------+ | | | |<-+ | | | Init | |3,5,6 |9 | | |--+ 7,8 | 9| +--------+ | | | | | 2,4| | | v | +--------+ 7 +--------+ | | |------>| |----------+ | Deg | | Up | | |<------| | +--------+ 8 +--------+ | ^ | | +--+ 2,3,4,5,6 Figure 4: LMP TE Link FSM In the above FSM, the sub-states that may be implemented when the link verification procedure is used have been omitted. 12.3. Data Link FSM The data link FSM defines the states and logics of operation of a port or component link within an LMP TE link. Operation of a data link is described in terms of FSM states and events. Data-bearing links can either be in the active (transmitting) mode, where Test messages are transmitted from them, or the passive (receiving) mode, where Test messages are received through them. For clarity, separate Lang et al [Page 30]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 FSMs are defined for the active/passive data-bearing links; however, a single set of data link states and events are defined. 12.3.1. Data Link States Any data link can be in one of the states described below. Every state corresponds to a certain condition of the TE link. Down: The data link has not been put in the resource pool (i.e., the link is not æin serviceÆ Test: The data link is being tested. An LMP Test message is periodically sent through the link. PasvTest: The data link is being checked for incoming test messages. Up/Free: The link has been successfully tested and is now put in the pool of resources (in-service). The link has not yet been allocated to data traffic. Up/Allocated: The link is UP and has been allocated for data traffic. 12.3.2. Data Link Events Data bearing link events are generated by the packet processing routines and by the FSMs of the associated control channel and the TE link. Every event has its number and a symbolic name. Description of possible data link events is given below: 1 :evCCUp: CC has gone up. 2 :evCCDown: LMP neighbor connectivity is lost. This indicates the last LMP control channel has failed between neighboring nodes. 3 :evStartTst: This is an external event that triggers the sending of Test messages over the data bearing link. 4 :evStartPsv: This is an external event that triggers the listening for Test messages over the data bearing link. 5 :evTestOK: Link verification was successful and the link can be used for path establishment. (a) This event indicates the Link Verification procedure (see Section 5) was successful for this data link and a TestStatusSuccess message was received over the control channel. (b) This event indicates the link is ready for path establishment, but the Link Verification procedure was not used. For Lang et al [Page 31]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 in-band signaling of the control channel, the control channel establishment may be sufficient to verify the link. 6 :evTestRcv: Test message was received over the data port and a TestStatusSuccess message is transmitted over the control channel. 7 :evTestFail: Link verification returned negative results. This could be because (a) a TestStatusFailure message was received, or (b) the Verification procedure has ended without receiving a TestStatusSuccess or TestStatusFailure message for the data link. 8 :evPsvTestFail:Link verification returned negative results. This indicates that a Test message was not detected and either (a) the VerifyDeadInterval has expired or (b) the Verification procedure has ended and the VerifyDeadInterval has not yet expired. 9 :evLnkAlloc: The data link has been allocated. 10:evLnkDealloc: The data link has been deallocated. 11:evTestRet: A retransmission timer has expired and the Test message is resent. 12:evSummaryFail:The LinkSummary did not match for this data port. 13:evLocalizeFail:A Failure has been localized to this data link. 14:evdcDown: The data channel is no longer available. Lang et al [Page 32]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 12.3.3. Active Data Link FSM Description Figure 5 illustrates operation of the LMP active data link FSM in a form of FSM state transition diagram. +------+ | |<-------+ +--------->| Down | | | +----| |<-----+ | | | +------+ | | | |5b 3| ^ | | | | | |7 | | | | v | | | | | +------+ | | | | | |<-+ | | | | | Test | |11 | | | | | |--+ | | | | +------+ | | | | 5a| 3^ | | | | | | | | | | v | | | |12 | +---------+ | | | +-->| |14 | | | | Up/Free |----+ | +---------| | | +---------+ | 9| ^ | | | | v |10 | +---------+ | | |13 | |Up/Alloc |------+ | | +---------+ Figure 5: Active LMP Data Link FSM Lang et al [Page 33]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 12.3.4. Passive Data Link FSM Description Figure 6 illustrates operation of the LMP passive data link FSM in a form of FSM state transition diagram. +------+ | |<------+ +---------->| Down | | | +-----| |<----+ | | | +------+ | | | |5b 4| ^ | | | | | |8 | | | | v | | | | | +----------+ | | | | | PasvTest | | | | | +----------+ | | | | 6| 4^ | | | | | | | | | | v | | | |12 | +---------+ | | | +--->| Up/Free |14 | | | | |---+ | +----------| | | +---------+ | 9| ^ | | | | v |10 | +---------+ | | |13 | |Up/Alloc |-----+ | | +---------+ Figure 6: Passive LMP Data Link FSM Lang et al [Page 34]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 13. LMP Message Formats All LMP messages are IP encoded (except, in some cases, the Test messages are limited by the transport mechanism for in-band messaging) and run over UDP with port number xxx - TBA (to be assigned) by IANA. 13.1. Common Header In addition to the standard IP header, all LMP messages (except, in some cases, the Test messages which are limited by the transport mechanism for in-band messaging) have the following common header: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Vers | (Reserved) | Flags | Msg Type | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | LMP Length | Checksum | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Vers: 4 bits Protocol version number. This is version 1. Flags: 8 bits. The following values are defined. All other values are reserved. 0x01: ControlChannelDown 0x02: LMP Restart This bit is set to indicate the LMP component has restarted. This flag may be reset to 0 when a Hello message is received with RcvSeqNum equal to the local TxSeqNum. Msg Type: 8 bits. The following values are defined. All other values are reserved. 1 = Config 2 = ConfigAck 3 = ConfigNack 4 = Hello 5 = BeginVerify 6 = BeginVerifyAck Lang et al [Page 35]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 7 = BeginVerifyNack 8 = EndVerify 9 = EndVerifyAck 10 = Test 11 = TestStatusSuccess 12 = TestStatusFailure 13 = TestStatusAck 14 = LinkSummary 15 = LinkSummaryAck 16 = LinkSummaryNack 17 = ChannelStatus 18 = ChannelStatusAck 19 = ChannelStatusRequest 20 = ChannelStatusResponse All of the messages are sent over the control channel EXCEPT the Test message, which is sent over the data link that is being tested. LMP Length: 16 bits The total length of this LMP message in bytes, including the common header and any variable-length objects that follow. Checksum: 16 bits The standard IP checksum of the entire contents of the LMP message, starting with the LMP message header. This checksum is calculated as the 16-bit one's complement of the one's complement sum of all the 16-bit words in the packet. If the packet's length is not an integral number of 16-bit words, the packet is padded with a byte of zero before calculating the checksum. 13.2. LMP Object Format LMP messages are built using objects. Each object is identified by its Object Class and Class-type. Each object has a name, which is Lang et al [Page 36]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 always capitalized in this document. LMP objects can be either negotiable or non-negotiable (identified by the N bit in the object header). Negotiable objects can be used to let the devices agree on certain values. Non-negotiable objects are used for announcement of specific values that do not need or do not allow negotiation. The format of the LMP object is as follows: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |N| C-Type | Class | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | // (object contents) // | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ N: 1 bit The N flag indicates if the object is negotiable (N=1) or non- negotiable (N=0). C-Type: 7 bits Class-type, unique within an Object Class. Values are defined in Section 14. Class: 8 bits The Class indicates the object type. Each object has a name, which is always capitalized in this document. Length: 16 bits The Length field indicates the length of the object in bytes, including the N, C-Type, Class, and Length fields. 13.3. Parameter Negotiation Messages 13.3.1. Config Message (Msg Type = 1) The Config message is used in the control channel negotiation phase of LMP. The contents of the Config message are built using LMP objects. The format of the Config message is as follows: <Config Message> ::= <Common Header> <LOCAL_CCID> <MESSAGE_ID> <LOCAL_NODE_ID> <CONFIG> The above transmission order SHOULD be followed. The MESSAGE_ID is within the scope of the CCID. Lang et al [Page 37]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 The Config message MUST be periodically transmitted until (1) it receives a ConfigAck or ConfigNack message, (2) a timeout expires and no ConfigAck or ConfigNack message has been received, or (3) it receives a Config message from the remote node and has lost the contention (e.g., the Node Id of the remote node is higher than the Node Id of the local node). Both the retransmission interval and the timeout period are local configuration parameters. 13.3.2. ConfigAck Message (Msg Type = 2) The ConfigAck message is used to acknowledge receipt of the Config message and indicate agreement on all parameters. <ConfigAck Message> ::= <Common Header> <LOCAL_CCID> <LOCAL_NODE_ID> <REMOTE_CCID> <MESSAGE_ID_ACK> <REMOTE_NODE_ID> The above transmission order SHOULD be followed. The contents of the REMOTE_CCID, MESSAGE_ID_ACK, and REMOTE_NODE_ID objects MUST be obtained from the Config message being acknowledged. 13.3.3. ConfigNack Message (Msg Type = 3) The ConfigNack message is used to acknowledge receipt of the Config message and indicate disagreement on non-negotiable parameters or propose other values for negotiable parameters. Parameters where agreement was reached MUST NOT be included in the ConfigNack Message. The format of the ConfigNack message is as follows: <ConfigNack Message> ::= <Common Header> <LOCAL_CCID> <LOCAL_NODE_ID> <REMOTE_CCID> <MESSAGE_ID_ACK> <REMOTE_NODE_ID> <CONFIG> The above transmission order SHOULD be followed. The contents of the REMOTE_CCID, MESSAGE_ID_ACK, and REMOTE_NODE_ID objects MUST be obtained from the Config message being negatively acknowledged. It is possible that multiple parameters may be invalid in the Config message. If a negotiable CONFIG object is included in the ConfigNack message, it MUST include acceptable values for the parameters. If the ConfigNack message includes CONFIG objects for non-negotiable parameters, they MUST be copied from the CONFIG objects received in the Config message. Lang et al [Page 38]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 If the ConfigNack message is received and only includes CONFIG objects that are negotiable, then a new Config message SHOULD be sent. The values in the CONFIG object of the new Config message SHOULD take into account the acceptable values included in the ConfigNack message. 13.4. Hello Message (Msg Type = 4) The format of the Hello message is as follows: <Hello Message> ::= <Common Header> <LOCAL_CCID> <HELLO> The above transmission order SHOULD be followed. The Hello message MUST be periodically transmitted at least once every HelloInterval msec. If no Hello message is received within the HelloDeadInterval, the control channel is assumed to have failed. 13.5. Link Verification 13.5.1. BeginVerify Message (Msg Type = 5) The BeginVerify message is sent over the control channel and is used to initiate the link verification process. The format is as follows: <BeginVerify Message> ::= <Common Header> <LOCAL_LINK_ID> <MESSAGE_ID> [<REMOTE_LINK_ID>] <BEGIN_VERIFY> The above transmission order SHOULD be followed. To limit the scope of Link Verification to a particular TE Link, the LOCAL_LINK_ID MUST be non-zero. If this field is zero, the data links can span multiple TE links and/or they may comprise a TE link that is yet to be configured. In the special case where the LOCAL_LINK_ID field is zero, the "Verify all Links" flag of the BEGIN_VERIFY object is used to distinguish between data links that span multiple TE links and those that have not yet been assigned to a TE link. The REMOTE_LINK_ID may be included if the local/remote Link Id mapping is known. The REMOTE_LINK_ID MUST be non-zero if included. The BeginVerify message MUST be periodically transmitted until (1) the node receives either a BeginVerifyAck or BeginVerifyNack message to accept or reject the verify process or (2) a timeout expires and no BeginVerifyAck or BeginVerifyNack message has been received. Both the retransmission interval and the timeout period are local configuration parameters. Lang et al [Page 39]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 13.5.2. BeginVerifyAck Message (Msg Type = 6) When a BeginVerify message is received and Test messages are ready to be processed, a BeginVerifyAck message MUST be transmitted. <BeginVerifyAck Message> ::= <Common Header> [<LOCAL_LINK_ID>] <MESSAGE_ID_ACK> <BEGIN_VERIFY_ACK> <VERIFY_ID> The above transmission order SHOULD be followed. The LOCAL_LINK_ID may be included if the local/remote Link Id mapping is known or learned through the BeginVerify message. The LOCAL_LINK_ID MUST be non-zero if included. The contents of the MESSAGE_ID_ACK object MUST be obtained from the BeginVerify message being acknowledged. The VERIFY_ID object contains a node-unique value that is assigned by the generator of the BeginVerifyAck message. This value is used to uniquely identify the Verification process from multiple LMP neighbors and/or parallel Test procedures between the same LMP neighbors. 13.5.3. BeginVerifyNack Message (Msg Type = 7) If a BeginVerify message is received and a node is unwilling or unable to begin the Verification procedure, a BeginVerifyNack message MUST be transmitted. <BeginVerifyNack Message> ::= <Common Header> [<LOCAL_LINK_ID>] <MESSAGE_ID_ACK> <ERROR_CODE> The above transmission order SHOULD be followed. The contents of the MESSAGE_ID_ACK object MUST be obtained from the BeginVerify message being negatively acknowledged. If the Verification process is not supported, the ERROR_CODE MUST indicate "Link Verification Procedure not supported". If Verification is supported, but the node unable to begin the procedure, the ERROR_CODE MUST indicate "Unwilling to verify". If a BeginVerifyNack message is received with such an ERROR_CODE, the node that originated the BeginVerify SHOULD schedule a BeginVerify retransmission after Rf seconds, where Rf is a locally defined parameter. Lang et al [Page 40]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 If the Verification Transport mechanism is not supported, the ERROR_CODE MUST indicate "Unsupported verification transport mechanism". If remote configuration of the TE Link Id is not supported and the REMOTE_LINK_ID object (included in the BeginVerify message) does not match any configured values, the ERROR_CODE MUST indicate "TE Link Id configuration error". The BeginVerifyNack uses BEGIN_VERIFY_ERROR_ C-Type 1. 13.5.4. EndVerify Message (Msg Type = 8) The EndVerify message is sent over the control channel and is used to terminate the link verification process. The EndVerify message may be sent at any time the initiating node desires to end the Verify procedure. The format is as follows: <EndVerify Message> ::= <Common Header> <MESSAGE_ID> <VERIFY_ID> The above transmission order SHOULD be followed. The EndVerify message will be periodically transmitted until (1) an EndVerifyAck message has been received or (2) a timeout expires and no EndVerifyAck message has been received. Both the retransmission interval and the timeout period are local configuration parameters. 13.5.5. EndVerifyAck Message (Msg Type =9) The EndVerifyAck message is sent over the control channel and is used to acknowledge the termination of the link verification process. The format is as follows: <EndVerifyAck Message> ::= <Common Header> <MESSAGE_ID_ACK> <VERIFY_ID> The above transmission order SHOULD be followed. The contents of the MESSAGE_ID_ACK object MUST be obtained from the EndVerify message being acknowledged. 13.5.6. Test Message (Msg Type = 10) The Test message is transmitted over the data link and is used to verify its physical connectivity. Unless explicitly stated in the Verify Transport Mechanism description for the BEGIN_VERIFY class, this is transmitted as an IP packet with payload format as follows: <Test Message> ::= <Common Header> <LOCAL_INTERFACE_ID> <VERIFY_ID> The above transmission order SHOULD be followed. Lang et al [Page 41]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 Note that this message is sent over a data link and NOT over the control channel. The transport mechanism for the Test message is negotiated using Verify Transport Mechanism field of the BEGIN_VERIFY object and the Verify Transport Response field of the BEGIN_VERIFY_ACK object (see Sections 14.8 and 14.9). The local (transmitting) node sends a given Test message periodically (at least once every VerifyInterval ms) on the corresponding data link until (1) it receives a correlating TestStatusSuccess or TestStatusFailure message on the control channel from the remote (receiving) node or (2) all active control channels between the two nodes have failed. The remote node will send a given TestStatus message periodically over the control channel until it receives either a correlating TestStatusAck message or an EndVerify message is received over the control channel. 13.5.7. TestStatusSuccess Message (Msg Type = 11) The TestStatusSuccess message is transmitted over the control channel and is used to transmit the mapping between the local Interface Id and the Interface Id that was received in the Test message. <TestStatusSuccess Message> ::= <Common Header> <LOCAL_LINK_ID> <MESSAGE_ID> <LOCAL_INTERFACE_ID> <REMOTE_INTERFACE_ID> <VERIFY_ID> The above transmission order SHOULD be followed. The contents of the REMOTE_INTERFACE_ID object MUST be obtained from the corresponding Test message being positively acknowledged. 13.5.8. TestStatusFailure Message (Msg Type = 12) The TestStatusFailure message is transmitted over the control channel and is used to indicate that the Test message was not received. <TestStatusFailure Message> ::= <Common Header> <MESSAGE_ID> <VERIFY_ID> The above transmission order SHOULD be followed. 13.5.9. TestStatusAck Message (Msg Type = 13) The TestStatusAck message is used to acknowledge receipt of the TestStatusSuccess or TestStatusFailure messages. <TestStatusAck Message> ::= <Common Header> <MESSAGE_ID_ACK> <VERIFY_ID> The above transmission order SHOULD be followed. Lang et al [Page 42]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 The contents of the MESSAGE_ID_ACK object MUST be obtained from the TestStatusSuccess or TestStatusFailure message being acknowledged. 13.6. Link Summary Messages 13.6.1. LinkSummary Message (Msg Type = 14) The LinkSummary message is used to synchronize the Interface Ids and correlate the properties of the TE link. The format of the LinkSummary message is as follows: <LinkSummary Message> ::= <Common Header> <MESSAGE_ID> <TE_LINK> <DATA_LINK> [<DATA_LINK>...] The above transmission order SHOULD be followed. The LinkSummary message can be exchanged at any time a link is not in the Verification process. The LinkSummary message MUST be periodically transmitted until (1) the node receives a LinkSummaryAck or LinkSummaryNack message or (2) a timeout expires and no LinkSummaryAck or LinkSummaryNack message has been received. Both the retransmission interval and the timeout period are local configuration parameters. 13.6.2. LinkSummaryAck Message (Msg Type = 15) The LinkSummaryAck message is used to indicate agreement on the Interface Id synchronization and acceptance/agreement on all the link parameters. It is on the reception of this message that the local node makes the TE Link Id associations. <LinkSummaryAck Message> ::= <Common Header> <MESSAGE_ID_ACK> The above transmission order SHOULD be followed. 13.6.3. LinkSummaryNack Message (Msg Type = 16) The LinkSummaryNack message is used to indicate disagreement on non- negotiated parameters or propose other values for negotiable parameters. Parameters where agreement was reached MUST NOT be included in the LinkSummaryNack message. <LinkSummaryNack Message> ::= <Common Header> <MESSAGE_ID_ACK> <ERROR_CODE> [<DATA_LINK>...] The above transmission order SHOULD be followed. The DATA_LINK objects MUST include acceptable values for all negotiable parameters. If the LinkSummaryNack includes DATA_LINK objects for non-negotiable parameters, they MUST be copied from the DATA_LINK objects received in the LinkSummary message. Lang et al [Page 43]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 If the LinkSummaryNack message is received and only includes negotiable parameters, then a new LinkSummary message SHOULD be sent. The values received in the new LinkSummary message SHOULD take into account the acceptable parameters included in the LinkSummaryNack message. The LinkSummaryNack message uses LINK_SUMMARY_ERROR C-Type 2. 13.7. Fault Management Messages 13.7.1. ChannelStatus Message (Msg Type = 17) The ChannelStatus message is sent over the control channel and is used to notify an LMP neighbor of the status of a data link. A node that receives a ChannelStatus message MUST respond with a ChannelStatusAck message. The format is as follows: <ChannelStatus Message> ::= <Common Header> <LOCAL_LINK_ID> <MESSAGE_ID> <CHANNEL_STATUS> The above transmission order SHOULD be followed. If the CHANNEL_STATUS object does not include any Interface Ids, then this indicates the entire TE Link has failed. 13.7.2. ChannelStatusAck Message (Msg Type = 18) The ChannelStatusAck message is used to acknowledge receipt of the ChannelStatus Message. The format is as follows: <ChannelStatusAck Message> ::= <Common Header> <MESSAGE_ID_ACK> The above transmission order SHOULD be followed. The contents of the MESSAGE_ID_ACK object MUST be obtained from the ChannelStatus message being acknowledged. 13.7.3. ChannelStatusRequest Message (Msg Type = 19) The ChannelStatusRequest message is sent over the control channel and is used to request the status of one or more data link(s). A node that receives a ChannelStatusRequest message MUST respond with a ChannelStatusResponse message. The format is as follows: <ChannelStatusRequest Message> ::= <Common Header> <LOCAL_LINK_ID> <MESSAGE_ID> [<CHANNEL_STATUS_REQUEST>] The above transmission order SHOULD be followed. Lang et al [Page 44]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 If the CHANNEL_STATUS_REQUEST object is not included, then the ChannelStatusRequest is being used to request the status of ALL of the data link(s) of the TE Link. 13.7.4. ChannelStatusResponse Message (Msg Type = 20) The ChannelStatusResponse message is used to acknowledge receipt of the ChannelStatusRequest Message and notify the LMP neighbor of the status of the data channel(s). The format is as follows: <ChannelStatusResponse Message> ::= <Common Header> <MESSAGE_ID_ACK> <CHANNEL_STATUS> The above transmission order SHOULD be followed. The contents of the MESSAGE_ID_ACK objects MUST be obtained from the ChannelStatusRequest message being acknowledged. 14. LMP Object Definitions 14.1. CCID (Control Channel ID) Class Class = 1. o C-Type = 1, LOCAL_CCID 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | CC_Id | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ CC_Id: 32 bits This MUST be node-wide unique and non-zero. The CC_Id identifies the control channel of the sender associated with the message. This object is non-negotiable. o C-Type = 2, REMOTE_CCID 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | CC_Id | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ CC_Id: 32 bits This identifies the remote nodeÆs CC_Id and MUST be non-zero. Lang et al [Page 45]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 This object is non-negotiable. 14.2. NODE_ID Classes Class = 2. o C-Type = 1, LOCAL_NODE_ID Class 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Node_Id (4 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Node_Id: This identities the node that originated the LMP packet. This object is non-negotiable. o C-Type = 2, REMOTE_NODE_ID Class 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Node_Id (4 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Node_Id: This identities the remote node. This object is non-negotiable. 14.3. LINK _ID Class Class = 3 o C-Type = 1, IPv4 LOCAL_LINK_ID o C-Type = 2, IPv4 REMOTE_LINK_ID 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Link_Id (4 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ o C-Type = 3, IPv6 LOCAL_LINK_ID o C-Type = 4, IPv6 REMOTE_LINK_ID Lang et al [Page 46]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + + | | + Link_Id (16 bytes) + | | + + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ o C-Type = 5, Unnumbered LOCAL_LINK_ID o C-Type = 6, Unnumbered REMOTE_LINK_ID 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Link_Id (4 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ o C-Type = 7, Reserved for OIF o C-Type = 8, Reserved for OIF Link_Id: For LOCAL_LINK_ID, this identifies the senderÆs Link associated with the message. For REMOTE_LINK_ID, this identifies the remote nodeÆs Link Id and MUST be non-zero. This object is non-negotiable. 14.4. INTERFACE_ID Class Class = 4 o C-Type = 1, IPv4 LOCAL_INTERFACE_ID o C-Type = 2, IPv4 REMOTE_INTERFACE_ID 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Interface_Id (4 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ o C-Type = 3, IPv6 LOCAL_INTERFACE_ID Lang et al [Page 47]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 o C-Type = 4, IPv6 REMOTE_INTERFACE_ID 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + + | | + Interface_Id (16 bytes) + | | + + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ o C-Type = 5, Unnumbered LOCAL_INTERFACE_ID o C-Type = 6, Unnumbered REMOTE_INTERFACE_ID 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Interface_Id (4 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Interface_Id: For the LOCAL_INTERFACE_ID, this identifies the data link (either port or component link). This value MUST be node-wide unique and non-zero. For the REMOTE_INTERFACE_ID, this identifies the remote nodeÆs data link (either port or component link). The Interface Id MUST be non-zero. This object is non-negotiable. 14.5. MESSAGE_ID Class Class = 5. o C-Type=1, MessageId 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Message_Id | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Message_Id: Lang et al [Page 48]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 The Message_Id field is used to identify a message. This value is incremented and only decreases when the value wraps. This is used for message acknowledgment. This object is non-negotiable. o C-Type = 2, MessageIdAck 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Message_Id | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Message_Id: The Message_Id field is used to identify the message being acknowledged. This value is copied from the MESSAGE_ID object of the message being acknowledged. This object is non-negotiable. 14.6. CONFIG Class Class = 6. o C-Type = 1, HelloConfig 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | HelloInterval | HelloDeadInterval | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ HelloInterval: 16 bits. Indicates how frequently the Hello packets will be sent and is measured in milliseconds (ms). HelloDeadInterval: 16 bits. If no Hello packets are received within the HelloDeadInterval, the control channel is assumed to have failed. The HelloDeadInterval is measured in milliseconds (ms). The HelloDeadInterval MUST be greater than the HelloInterval, and SHOULD be at least 3 times the value of HelloInterval. If the fast keep-alive mechanism of LMP is not used, the HelloInterval and HelloDeadInterval MUST be set to zero. 14.7. HELLO Class Lang et al [Page 49]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 Class = 7 o C-Type = 1, Hello 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | TxSeqNum | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | RcvSeqNum | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ TxSeqNum: 32 bits This is the current sequence number for this Hello message. This sequence number will be incremented when the sequence number is reflected in the RcvSeqNum of a Hello packet that is received over the control channel. TxSeqNum=0 is not allowed. TxSeqNum=1 is reserved to indicate that the control channel has booted or restarted. RcvSeqNum: 32 bits This is the sequence number of the last Hello message received over the control channel. RcvSeqNum=0 is reserved to indicate that a Hello message has not yet been received. This object is non-negotiable. 14.8. BEGIN_VERIFY Class Class = 8. o C-Type = 1 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Flags | VerifyInterval | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Number of Data Links | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | EncType | (Reserved) | Verify Transport Mechanism | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | TransmissionRate | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Wavelength | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Lang et al [Page 50]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 Flags: 16 bits The following flags are defined: 0x01 Verify all Links If this bit is set, the verification process checks all unallocated links; else it only verifies new ports or component links that are to be added to this TE link. 0x02 Data Link Type If set, the data links to be verified are ports, otherwise they are component links VerifyInterval: 16 bits This is the interval between successive Test messages and is measured in milliseconds (ms). Number of Data Links: 32 bits This is the number of data links that will be verified. EncType: 8 bits This is the encoding type of the data link. The defined EncType values are consistent with the Link Encoding Type values of [GMPLS-SIG] Verify Transport Mechanism: 16 bits This defines the transport mechanism for the Test Messages. The scope of this bit mask is restricted to each link encoding type. The local node will set the bits corresponding to the various mechanisms it can support for transmitting LMP test messages. The receiver chooses the appropriate mechanism in the BeginVerifyAck message. For SONET/SDH Encoding Type, the following flags are defined: 0x01 J0-16: 16 byte J0 Test Message Capable of transmitting Test messages using J0 overhead bytes with string length of 16 bytes (with CRC-7). See table 4 of ITU G.707 [G707] for the 16-byte J0 definition. The definition of CRC-7 is found in Annex B of ITU G.707. Note that Due to the byte limitation, the Test message is NOT sent as an IP packet and as such, no L2 encapsulation is used. A special Test message format is defined as follows: Lang et al [Page 51]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 The Test message is a 15-byte message, where the 7 most significant bits (MSb) of each byte are usable. Due to the byte limitation, the LMP Header is not included. The first usable 32 bits MUST be the VerifyId that was received in the VERIFY_ID object of the BeginVerifyAck message. The second usable 32 bits MUST be the Interface_Id. The next usable 8 bits are used to determine the address type of the Interface_Id. For IPv4, this value is 1. For unnumbered, this value is 3. The remaining bits are Reserved. Note that this Test Message format is only valid when the Interface_Id is either IPv4 or unnumbered. 0x02 J0-64: 64 byte J0 Test Message Capable of transmitting Test messages using J0 overhead bytes with string length of 64 bytes (see GR- 253-CORE [GR253]). Note that this is only appropriate for SONET encoding and not SDH encoding. The Test message is sent as an IP packet as defined above. 0x04 DCCS: Test Message over the Section DCC Capable of transmitting Test messages using the DCC Section Overhead bytes with bit-oriented HDLC framing format. The Test message is sent as an IP packet as defined above. 0x08 DCCL: Test Message over the Line DCC Capable of transmitting Test messages using the DCC Line Overhead bytes with bit-oriented HDLC framing format. The Test message is sent as an IP packet as defined above. 0x10 Payload: Test Message transmitted in the payload Capable of transmitting Test messages in the payload using Packet over SONET framing using the encoding type specified in the EncType field. The Test message is sent as an IP packet as defined above. Lang et al [Page 52]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 0x20 GigE: Capable of transmitting Test messages in the payload TransmissionRate: 32 bits This is the transmission rate of the data link over which the Test messages will be transmitted. This is expressed in bytes per second and represented in IEEE floating point format. Wavelength: 32 bits When a data link is assigned to a port or component link that is capable of transmitting multiple wavelengths (e.g., a fiber or waveband-capable port), it is essential to know which wavelength the test messages will be transmitted over. This value corresponds to the wavelength at which the Test messages will be transmitted over and has local significance. If there is no ambiguity as to the wavelength over which the message will be sent, then this value SHOULD be set to 0. 14.9. BEGIN_VERIFY_ACK Class Class = 9. o C-Type = 1 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | VerifyDeadInterval | Verify_Transport_Response | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ VerifyDeadInterval: 16 bits If a Test message is not detected within the VerifyDeadInterval, then a node will send the TestStatusFailure message for that data link. Verify_Transport_Response: 16 bits The recipient of the BeginVerify message (and the future recipient of the TEST messages) chooses the transport mechanism from the various types that are offered by the transmitter of the Test messages. One and only one bit MUST be set in the verification transport response. This object is non-negotiable. 14.10. VERIFY_ID Class Class = 10. Lang et al [Page 53]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 o C-Type = 1 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | VerifyId | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ VerifyId: 32 bits This is used to differentiate Test messages from different TE links and/or LMP peers. This is a node-unique value that is assigned by the recipient of the BeginVerify message. This object is non-negotiable. 14.11. TE_LINK Class Class = 11. o C-Type = 1, IPv4 TE_LINK 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Flags | (Reserved) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Local_Link_Id (4 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Remote_Link_Id (4 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ o C-Type = 2, IPv6 TE_LINK 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Flags | (Reserved) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + + | | + Local_Link_Id (16 bytes) + | | + + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + + | | + Remote_Link_Id (16 bytes) + Lang et al [Page 54]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 | | + + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ o C-Type = 3, Unnumbered TE_LINK 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Flags | (Reserved) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Local_Link_Id (4 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Remote_Link_Id (4 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ o C-Type = 4, Reserved for OIF Flags: 8 bits The following flags are defined. All other values are reserved. 0x01 Fault Management Supported. 0x02 Link Verification Supported. Local_Link_Id: This identifies the nodeÆs local Link Id and MUST be non-zero. Remote_Link_Id: This identifies the remote nodeÆs Link Id and MUST be non-zero. 14.12. DATA_LINK Class Class = 12. o C-Type = 1, IPv4 DATA_LINK 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Flags | (Reserved) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Local_Interface_Id (4 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Remote_Interface_Id (4 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | // (Subobjects) // | | Lang et al [Page 55]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ o C-Type = 2, IPv6 DATA_LINK 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Flags | (Reserved) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + + | | + Local_Interface_Id (16 bytes) + | | + + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + + | | + Remote_Interface_Id (16 bytes) + | | + + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | // (Subobjects) // | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ o C-Type = 3, Unnumbered DATA_LINK 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Flags | (Reserved) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Local_Interface_Id (4 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Remote_Interface_Id (4 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | // (Subobjects) // | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Flags: 8 bits The following flags are defined. All other values are reserved. 0x01 Interface Type: If set, the data link is a port, otherwise it is a component link. Lang et al [Page 56]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 0x02 Allocated Link: If set, the data link is currently allocated for user traffic. If a single Interface_Id is used for both the transmit and receive data links, then this bit only applies to the transmit interface. 0x04 Failed Link: If set, the data link is failed and not suitable for user traffic. Local_Interface_Id: This is the local identifier of the data link. This MUST be node-wide unique and non-zero. Remote_Interface_Id: This is the remote identifier of the data link. This MUST be non-zero. Subobjects The contents of the DATA_LINK object consist of a series of variable-length data items called subobjects. The subobjects are defined in section 14.12.1 below. A DATA_LINK object may contain more than one subobject. More than one subobject of the same Type may appear if multiple capabilities are supported over the data link. 14.12.1. Data Link Subobjects The contents of the DATA_LINK object include a series of variable- length data items called subobjects. Each subobject has the form: 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+---------------//------------ -+ | Type | Length | (Subobject contents) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+--------------//---------------+ Type: 8 bits The Type indicates the type of contents of the subobject. Currently defined values are: Type = 1, Interface Switching Capability Length: 8 bits The Length contains the total length of the subobject in bytes, including the Type and Length fields. The Length MUST be at least 4, and MUST be a multiple of 4. Lang et al [Page 57]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 14.12.1.1. Subobject Type 1: Interface Switching Capability 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type | Length | Switching Cap | EncType | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Minimum Reservable Bandwidth | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Maximum Reservable Bandwidth | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Switching Capability: 8 bits This is used to identify the local Interface Switching Capability of the TE link as defined in [GMPLS-SIG]. EncType: 8 bits This is the encoding type of the data link. The defined EncType values are consistent with the Link Encoding Type values of [GMPLS-SIG]. Minimum Reservable Bandwidth: 32 bits This is measured in bytes per second and represented in IEEE floating point format. Maximum Reservable Bandwidth: 32 bits This is measured in bytes per second and represented in IEEE floating point format. If the interface only supports a fixed rate, the minimum and maximum bandwidth fields are set to the same value. 14.12.1.2. Subobject Type 2: Wavelength 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type | Length | (Reserved) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Wavelength | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Wavelength: 32 bits This value indicates the wavelength carried over the port. Values used in this field only have significance between two neighbors. Lang et al [Page 58]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 14.13. CHANNEL_STATUS Class Class = 13 o C-Type = 1, IPv4 INTERFACE_ID 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Interface Id (4 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |A| Channel Status | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | : | // : // | : | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Interface Id (4 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |A| Channel Status | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ o C-Type = 2, IPv6 INTERFACE_ID 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + + | | + Interface Id (16 bytes) + | | + + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |A| Channel Status | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | : | // : // | : | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + + | | + Interface Id (16 bytes) + | | + + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |A| Channel Status | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Lang et al [Page 59]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 o C-Type = 3, Unnumbered INTERFACE_ID 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Interface Id (4 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |A| Channel Status | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | : | // : // | : | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Interface Id (4 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |A|D| Channel Status | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Active bit: 1 bit This indicates that the Channel is allocated to user traffic and the data link should be actively monitored. Direction bit: 1 bit This indicates the direction (transmit/receive) of the data channel referred to in the CHANNEL_STATUS object. If set, this indicates the data channel is in the transmit direction. Channel_Status: 30 bits This indicates the status condition of a data channel. The following values are defined. All other values are reserved. 1 Signal Okay (OK): Channel is operational 2 Signal Degrade (SD): A soft failure caused by a BER exceeding a preselected threshold. The specific BER used to define the threshold is configured. 3 Signal Fail (SF): A hard signal failure including (but not limited to) loss of signal (LOS), loss of frame (LOF), or Line AIS. This object contains one or more Interface Ids followed by a Channel_Status field. To indicate the status of the entire TE Link, there MUST only be one Interface Id and it MUST be zero. This object is non-negotiable. 14.14. CHANNEL_STATUS_REQUEST Class Lang et al [Page 60]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 Class = 14 o C-Type = 1, IPv4 INTERFACE_ID 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Interface Id (4 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | : | // : // | : | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Interface Id (4 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ This object contains one or more Interface Ids. The Length of this object is 4 + 4N in bytes, where N is the number of Interface Ids. o C-Type = 2, IPv4 INTERFACE_ID 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + + | | + Interface Id (16 bytes) + | | + + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | : | // : // | : | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + + | | + Interface Id (16 bytes) + | | + + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ This object contains one or more Interface Ids. The Length of this object is 4 + 16N in bytes, where N is the number of Interface Ids. Lang et al [Page 61]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 o C-Type = 3, Unnumbered INTERFACE_ID 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Interface Id (4 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | : | // : // | : | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Interface Id (4 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ This object contains one or more Interface Ids. The Length of this object is 4 + 4N in bytes, where N is the number of Interface Ids. This object is non-negotiable. 14.15. ERROR_CODE Class Class = 20. o C-Type = 1, BEGIN_VERIFY_ERROR 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ERROR CODE | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ The following bit-values are defined: 0x01 = Link Verification Procedure not supported for this TE Link. 0x02 = Unwilling to verify at this time 0x04 = Unsupported verification transport mechanism 0x08 = TE Link Id configuration error All other values are Reserved. Multiple bits may be set to indicate multiple errors. This object is non-negotiable. If a BeginVerifyNack message is received with Error Code 2, the node that originated the BeginVerify SHOULD schedule a BeginVerify retransmission after Rf seconds, where Rf is a locally defined parameter. Lang et al [Page 62]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 o C-Type = 2, LINK_SUMMARY_ERROR 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ERROR CODE | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ The following bit-values are defined: 0x01 = Unacceptable non-negotiable LINK_SUMMARY parameters 0x02 = Renegotiate LINK_SUMMARY parameters 0x04 = Bad Received Remote_Link_Id 0x08 = Bad TE Link Object 0x10 = Bad Data Link Object All other values are Reserved. Multiple bits may be set to indicate multiple errors. This object is non-negotiable. 15. Security Considerations Security is discussed in [LMP-SEC]. 16. Intellectual Property Considerations The IETF takes no position regarding the validity or scope of any intellectual property or other rights that might be claimed to pertain to the implementation or use of the technology described in this document or the extent to which any license under such rights might or might not be available; neither does it represent that it has made any effort to identify any such rights. Information on the IETF's procedures with respect to rights in standards-track and standards-related documentation can be found in BCP-11. Copies of claims of rights made available for publication and any assurances of licenses to be made available, or the result of an attempt made to obtain a general license or permission for the use of such proprietary rights by implementers or users of this specification can be obtained from the IETF Secretariat. The IETF invites any interested party to bring to its attention any copyrights, patents or patent applications, or other proprietary rights which may cover technology that may be required to practice this standard. Please address the information to the IETF Executive Director. 17. References 17.1. Normative References Lang et al [Page 63]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 [RFC2026] Bradner, S., "The Internet Standards Process -- Revision 3," BCP 9, RFC 2026, October 1996. [BUNDLE] Kompella, K., Rekhter, Y., Berger, L., "Link Bundling in MPLS Traffic Engineering," Internet Draft, draft- kompella-mpls-bundle-05.txt, (work in progress), February 2001. [RFC2961] Berger, L., Gan, D., et al, "RSVP Refresh Overhead Reduction Extensions," RFC 2961, April 2001. [GMPLS-SIG] Ashwood-Smith, P., Banerjee, A., et al, "Generalized MPLS - Signaling Functional Description," Internet Draft, draft-ietf-mpls-generalized-signaling-06.txt, (work in progress), October 2001. [G707] ITU-T G.707, "Network node interface for the synchronous digital hierarchy (SDH)," March 1996. [GR253] GR-253-CORE, "Synchronous Optical Network (SONET) Transport Systems: Common Generic Criteria," Telcordia Technologies, Issue 3, September 2000. [LMP-SEC] Ramamoorthi,S. and Zinin, A., "LMP Security Mechanism," Internet Draft, draft-sankar-lmp-sec-00.txt, (work in progress), Internet Draft, February 2002. 17.2. Informative References [LAMBDA] Awduche, D. O., Rekhter, Y., Drake, J., Coltun, R., "Multi-Protocol Lambda Switching: Combining MPLS Traffic Engineering Control with Optical Crossconnects," Internet Draft, draft-awduche-mpls-te-optical-03.txt, (work in progress), April 2001. [RFC3209] Awduche, D. O., Berger, L, et al, "Extensions to RSVP for LSP Tunnels," Internet Draft, RFC3209 December 2001. [RFC3219] Jamoussi, B., ed., "Constraint-Based LSP Setup using LDP," RFC3219, January 2002. [OSPF-TE] Katz, D., Yeung, D., Kompella, K., "Traffic Engineering Extensions to OSPF," Internet Draft, draft-katz-yeung- ospf-traffic-04.txt, (work in progress), February 2001. [ISIS-TE] Li, T., Smit, H., "IS-IS extensions for Traffic Engineering," Internet Draft,draft-ietf-isis-traffic- 02.txt, (work in progress), September 2000. 18. Acknowledgements The authors would like to thank Andre Fredette for his many contributions to this draft. We would also like to thank Ayan Banerjee, George Swallow, Andre Fredette, Adrian Farrel, Vinay Ravuri, and David Drysdale for their insightful comments and suggestions. We would also like to thank John Yu, Suresh Katukam, and Greg Bernstein for their helpful suggestions for the in-band control channel applicability. Finally, we would like to thank Dimitri Papadimitriou for his contributions to the SONET/SDH test procedures. Lang et al [Page 64]
Internet Draft draft-ietf-ccamp-lmp-04.txt June 2002 19. Contributors Jonathan P. Lang Krishna Mitra Calient Networks Calient Networks 25 Castilian Drive 5853 Rue Ferrari Goleta, CA 93117 San Jose, CA 95138 Email: jplang@calient.net email: krishna@calient.net John Drake Kireeti Kompella Calient Networks Juniper Networks, Inc. 5853 Rue Ferrari 385 Ravendale Drive San Jose, CA 95138 Mountain View, CA 94043 email: jdrake@calient.net email: kireeti@juniper.net Yakov Rekhter Lou Berger Juniper Networks, Inc. Movaz Networks 385 Ravendale Drive email: lberger@movaz.com Mountain View, CA 94043 email: yakov@juniper.net Debanjan Saha Debashis Basak Tellium Optical Systems Accelight Networks 2 Crescent Place 70 Abele Road, Suite 1201 Oceanport, NJ 07757-0901 Bridgeville, PA 15017-3470 email: dsaha@tellium.com email: dbasak@accelight.com Hal Sandick Alex Zinin Shepard M.S. Alcatel 2401 Dakota Street email: zinin@psg.com Durham, NC 27705 email: sandick@nc.rr.com Bala Rajagopalan Tellium Optical Systems 2 Crescent Place Oceanport, NJ 07757-0901 email: braja@tellium.com 20. Contact Address Jonathan P. Lang Calient Networks 25 Castilian Drive Goleta, CA 93117 Email: jplang@calient.net Lang et al [Page 65]
