Internet Draft J. Quittek Document: draft-ietf-rohc-mib-rtp-00.txt H. Hartenstein Expires: May 2002 M. Stiemerling NEC Europe Ltd. November 2001 Definitions of Managed Objects for Robus Header Compression <draft-ietf-rohc-mib-rtp-00.txt> Status of this Memo This document is an Internet-Draft and is in full conformance with all provisions of Section 10 of RFC 2026. 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 Distribution of this document is unlimited. Copyright Notice Copyright (C) The Internet Society (2001). All Rights Reserved. Abstract This memo defines a portion of the Management Information Base (MIB) for use with network management protocols in the Internet community. In particular, it describes a set of managed objects that allow monitoring of running instances of robust header compression. Quittek, Hartenstein, Stiemerling [Page 1]
Internet-Draft ROHC MIB November 2001 Table of Contents 1 Introduction ................................................. 2 2 The SNMP Management Framework ................................ 2 3 Overview ..................................................... 3 4 Structure of the MIB ......................................... 4 4.1 The rohcIfGroup ............................................ 4 4.2 The rohcHeaderGroup ........................................ 4 4.3 The rohcChannelGroup ....................................... 5 4.4 The rohcCompressorGroup .................................... 5 4.5 The rohcDecompressorGroup .................................. 5 4.6 The rohcStatisticsGroup .................................... 5 5 Definitions .................................................. 6 6 Security Considerations ...................................... 26 7 References ................................................... 27 8 Authors' Addresses ........................................... 28 9 Full Copyright Statement ..................................... 30 1. Introduction This memo defines a portion of the Management Information Base (MIB) for use with network management protocols in the Internet community. In particular, it describes a set of managed objects that allow monitoring of running instances of robust header compression. The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC 2119 [RFC2119]. 2. The SNMP Management Framework The SNMP Management Framework presently consists of five major components: o An overall architecture, described in RFC 2571 [RFC2571]. o Mechanisms for describing and naming objects and events for the purpose of management. The first version of this Structure of Management Information (SMI) is called SMIv1 and described in STD 16, RFC 1155 [RFC1155], STD 16, RFC 1212 [RFC1212] and RFC 1215 [RFC1215]. The second version, called SMIv2, is described in STD 58, RFC 2578 [RFC2578], STD 58, RFC 2579 [RFC2579] and STD 58, RFC 2580 [RFC2580]. o Message protocols for transferring management information. The first version of the SNMP message protocol is called SNMPv1 and described in STD 15, RFC 1157 [RFC1157]. A second version of the SNMP message protocol, which is not an Internet standards Quittek, Hartenstein, Stiemerling [Page 2]
Internet-Draft ROHC MIB November 2001 track protocol, is called SNMPv2c and described in RFC 1901 [RFC1901] and RFC 1906 [RFC1906]. The third version of the message protocol is called SNMPv3 and described in RFC 1906 [RFC1906], RFC 2572 [RFC2572] and RFC 2574 [RFC2574]. o Protocol operations for accessing management information. The first set of protocol operations and associated PDU formats is described in STD 15, RFC 1157 [RFC1157]. A second set of protocol operations and associated PDU formats is described in RFC 1905 [RFC1905]. o A set of fundamental applications described in RFC 2573 [RFC2573] and the view-based access control mechanism described in RFC 2575 [RFC2575]. A more detailed introduction to the current SNMP Management Framework can be found in RFC 2570 [RFC2570]. Managed objects are accessed via a virtual information store, termed the Management Information Base or MIB. Objects in the MIB are defined using the mechanisms defined in the SMI. This memo specifies a MIB module that is compliant to the SMIv2. A MIB conforming to the SMIv1 can be produced through the appropriate translations. The resulting translated MIB must be semantically equivalent, except where objects or events are omitted because no translation is possible (use of Counter64). Some machine readable information in SMIv2 will be converted into textual descriptions in SMIv1 during the translation process. However, this loss of machine readable information is not considered to change the semantics of the MIB. 3. Overview This section describes the basic model of RObust Header Compression (ROHC, [RFC3095]) used in developing the ROHC MIB module. ROHC presents a framework for IP header compression that allows flexible adjustment of compression efficiency versus robustness against channel errors depending on the underlying channel characteristics. ROHC introduces header compressors/decompressors at the end-points (interfaces) of (wireless) channels on which ROHC header-compressed packets flow. ROHC exploits the temporal redundancy in successive packet headers of a packet flow by storing non-changing fields of the headers as well as reference values of predictably changing fields as context information. When the context information for a packet flow is also established at the decompressor, only delta-information and Quittek, Hartenstein, Stiemerling [Page 3]
Internet-Draft ROHC MIB November 2001 unpredictably changing header fields have to be sent over the channel. Since the context information will change over time, the decompressor's information on the context has to be kept 'in sync'. In order to update contexts at the decompressor, various header types can be used to efficiently transmit the information needed for the update. ROHC specifies three modes of operation: i) unidirectional mode where the decompressor does not give feedback to the compressor, ii) bidirectional reliable mode, and iii) bidirectional optimistic mode. The control mechanisms that determine what header types are allowed to be sent or to be decompressed are modeled as state machines. Detection of residual bit errors or damaged contexts at the decompressor as well as repair strategies are based on Cyclic Redundancy Checks (CRC) included in the compressed headers. This document specifies the ROHC MIB module in order to provide means for managing ROHC implementation via SNMP and within the IETF management framework. The objects defined support configuration management, fault management and performance monitoring. For configuration management implementation parameters (Section 6.3. of RFC 3095) and configuration parameters (including the ones specified in 5.1.1 of RFC 3095) can be verified by using the ROHC MIB. For fault management compressor/decompressor state and mode can be checked and the compressor context can be reinitialized. For performance management a set of statistics is provided including the number of flows that have used ROHC, the current and long term compression ratio, the number of reinitializations and the number of packets sent or received with different header types. 4. Structure of the MIB This section presents the structure of the MIB. The objects are arranged into the following groups: o interfaces group (rohcIfGroup) o header group (rohcHeaderGroup) o channel group (rohcChannelGroup) o compressor group (rohcCompressorGroup) o decompressor group (rohcDecompressorGroup) Quittek, Hartenstein, Stiemerling [Page 4]
Internet-Draft ROHC MIB November 2001 o statistics group (rohcStatisticsGroup) 4.1. The rohcIfGroup The rohcIfGroup consists of a single table listing all interfaces of the managed node, on which robust header compression is available. Different interfaces might use different versions of ROHC. This table provides information about the vendor and version number of the ROHC implementation per interface and of its common properties and current status. 4.2. The rohcHeaderGroup The rohcHeaderGroup consists of a single table listing per interface all header types supported by this instance of robust header compression. 4.3. The rohcChannelGroup The rohcChannelGroup consists of two tables, the rohcChannelTable and the rohcProfileTable. The rohcChannelTable lists all channels per interface with their general properties described in Section 5.1.1. of RFC 3095. Furthermore, it includes counters for incoming and outgoing flows per channel, which used ROHC. The rohcProfileTable lists the set of profiles supported by the decompressor. The profiles are listed by their number as described in Section 5.1.2. of RFC 3095. 4.4. The rohcCompressorGroup The rohcCompressorGroup consists of three tables, the rohcCompressorTable, the rohcPacketSizeTable, and the rohcPayloadSizeTable. The rohcCompressorTable lists and describes all compressor contexts per channel. The description includes context ID, state, mode, and profile of the compressor contex as well as the number of allowed packet sizes and the number of used packet sizes. A special object called rohcCompressorReinit allows the network manager to reinitialize the compressor context by setting the object. The rohcPacketSizeTable lists all allowed packet sizes per compressor context. Used packet sizes are marked. This table reflects the information contained in parameters PACKET_SIZES_ALLOWED and PACKET_SIZES_USED, as defined in RFC 3095, Section 6.3.1. The rohcPayloadSizeTable reflects the information contained in Quittek, Hartenstein, Stiemerling [Page 5]
Internet-Draft ROHC MIB November 2001 parameter PAYLOAD_SIZES, as defined in RFC 3095, Section 6.3.1. 4.5. The rohcDecompressorGroup The rohcDecompressorGroup consists of a single table listing and describing all decompressor contexts. The description includes context ID, state, mode, and profile of the decompressor contex as well as the depth of reverse compression. 4.6. The rohcStatisticsGroup The rohcStatisticsGroup consists of three tables, the rohcOutPacketCounterTable, the rohcInPacketCounterTable, and the rohcErrorTable. The first two tables contain counters per context and per header type for incoming and outgoing packets, repectively. The rohcErrorTable contains counters for different error types. Furthermore, some elements of the rohcCompressorTable and the rohcDecompressorTable belong to the rohcStatisticsGroup. They contain compression ratio indicatiors for each compressor context, packet counters per context, and reinitialization counters. 5. Definitions ROHC-MIB DEFINITIONS ::= BEGIN IMPORTS MODULE-IDENTITY, OBJECT-TYPE, Integer32, experimental FROM SNMPv2-SMI TEXTUAL-CONVENTION, TimeInterval, TruthValue FROM SNMPv2-TC MODULE-COMPLIANCE, OBJECT-GROUP FROM SNMPv2-CONF SnmpAdminString FROM SNMP-FRAMEWORK-MIB ifIndex FROM IF-MIB; rohcMIB MODULE-IDENTITY LAST-UPDATED "200111130837Z" ORGANIZATION "IETF Robust Header Compression Working Group" CONTACT-INFO "Juergen Quittek NEC Europe Ltd. Quittek, Hartenstein, Stiemerling [Page 6]
Internet-Draft ROHC MIB November 2001 Network Laboratories Adenauerplatz 6 69221 Heidelberg Germany Tel: +49 6221 90511-15 E-mail: quittek@ccrle.nec.de" DESCRIPTION "This MIB module defines a set of objects that for monitoring and configuring robust header compression." ::= { experimental 55555 } -- Number to be requested from IANA. 55555 is just a placeholder. RohcChannelIndex ::= TEXTUAL-CONVENTION STATUS current DESCRIPTION "An index identifying a channel." SYNTAX Integer32 (1..2147483647) -- -- The groups defined within this MIB module: -- rohcObjects OBJECT IDENTIFIER ::= { rohcMIB 1 } rohcConformance OBJECT IDENTIFIER ::= { rohcMIB 2 } -- -- Interfaces supporting ROHC -- -- This group define a table which lists all running instances -- of robust header compression per interface at the managed node. -- Even if a single instance serves more than one interface, -- it is listed for each interface. -- rohcIfTable OBJECT-TYPE SYNTAX SEQUENCE OF RohcIfEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "This table lists running instance of robust header compression." ::= { rohcObjects 1 } rohcIfEntry OBJECT-TYPE SYNTAX RohcIfEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "An entry describing a particular running instance of robust header compression." INDEX { ifIndex } Quittek, Hartenstein, Stiemerling [Page 7]
Internet-Draft ROHC MIB November 2001 ::= { rohcIfTable 1 } RohcIfEntry ::= SEQUENCE { rohcIfVendor OBJECT IDENTIFIER, rohcIfVersion SnmpAdminString, rohcIfDescr SnmpAdminString, rohcIfClockRes TimeInterval, rohcIfStatus INTEGER } rohcIfVendor OBJECT-TYPE SYNTAX OBJECT IDENTIFIER MAX-ACCESS read-only STATUS current DESCRIPTION "An object identifer which identifies the vendor who provides the implementation of robust header description. This object identifer SHALL point to the object identifier directly below the enterprise object identifier {1 3 6 1 4 1} allocated for the vendor. The value must be the object identifier {0 0} if the vendor is not known." ::= { rohcIfEntry 2 } rohcIfVersion OBJECT-TYPE SYNTAX SnmpAdminString (SIZE (0..32)) MAX-ACCESS read-only STATUS current DESCRIPTION "The version number of the implementation of robust header compression. The zero-length string shall be used if the implementation does not have a version number. It is suggested that the version number consist of one or more decimal numbers separated by dots, where the first number is called the major version number." ::= { rohcIfEntry 3 } rohcIfDescr OBJECT-TYPE SYNTAX SnmpAdminString MAX-ACCESS read-only STATUS current DESCRIPTION "A textual description of the implementation." ::= { rohcIfEntry 4 } rohcIfClockRes OBJECT-TYPE SYNTAX TimeInterval UNITS "centi-seconds" MAX-ACCESS read-only STATUS current Quittek, Hartenstein, Stiemerling [Page 8]
Internet-Draft ROHC MIB November 2001 DESCRIPTION "This object indicates the system clock resolution in units of centi-seconds. A zero (0) value means that there is no clock available. Please note, that RFC 3095 defines the clock resolution to be defined in milliseconds." ::= { rohcIfEntry 5 } rohcIfStatus OBJECT-TYPE SYNTAX INTEGER { enabled(1), disabled(2) } MAX-ACCESS read-only STATUS current DESCRIPTION "Status of the implementation of ROHC at this interface." ::= { rohcIfEntry 6 } -- -- Supported Headers. -- -- This group define a table which lists all header types -- supported by this instance of robust header compression. -- rohcHeaderTable OBJECT-TYPE SYNTAX SEQUENCE OF RohcHeaderEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "This table lists supported header types." ::= { rohcObjects 2 } rohcHeaderEntry OBJECT-TYPE SYNTAX RohcHeaderEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "An entry describing a particular supported header type ." INDEX { ifIndex, rohcHeaderIndex } ::= { rohcHeaderTable 1 } RohcHeaderEntry ::= SEQUENCE { rohcHeaderIndex Integer32, rohcHeaderString SnmpAdminString, rohcHeaderDescr SnmpAdminString } rohcHeaderIndex OBJECT-TYPE SYNTAX Integer32 (1..2147483647) Quittek, Hartenstein, Stiemerling [Page 9]
Internet-Draft ROHC MIB November 2001 MAX-ACCESS not-accessible STATUS current DESCRIPTION "The locally arbitrary, but unique identifier associated with this supported header type. The value is expected to remain constant at least from one re-initialization of the entity's network management system to the next re-initialization." ::= { rohcHeaderEntry 2} rohcHeaderString OBJECT-TYPE SYNTAX SnmpAdminString (SIZE (0..32)) -- length of 32 sufficient? MAX-ACCESS read-only STATUS current DESCRIPTION "The name of the header type or at least a string uniquely identifying the header type." ::= { rohcHeaderEntry 3 } rohcHeaderDescr OBJECT-TYPE SYNTAX SnmpAdminString MAX-ACCESS read-only STATUS current DESCRIPTION "A textual description of the header type." ::= { rohcHeaderEntry 4 } -- -- Channels -- -- This group defines a table listing all channels for which -- robust header compression is activated, and a table listing -- all supported profiles per channel -- rohcChannelObjects OBJECT IDENTIFIER ::= { rohcObjects 3 } rohcChannelTable OBJECT-TYPE SYNTAX SEQUENCE OF RohcChannelEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "This table lists and describes all used channels per interface." ::= { rohcChannelObjects 1 } rohcChannelEntry OBJECT-TYPE SYNTAX RohcChannelEntry MAX-ACCESS not-accessible Quittek, Hartenstein, Stiemerling [Page 10]
Internet-Draft ROHC MIB November 2001 STATUS current DESCRIPTION "An entry describing a particular script. Every script that is stored in non-volatile memory is required to appear in this script table." INDEX { ifIndex, rohcChannelIndex } ::= { rohcChannelTable 1 } RohcChannelEntry ::= SEQUENCE { rohcChannelIndex RohcChannelIndex, rohcChannelMaxCID Integer32, rohcChannelLargeCIDs TruthValue, rohcChannelFeedbackFor RohcChannelIndex, rohcChannelMRRU Integer32, rohcChannelCompressedFlows Counter32, rohcChannelDecompressedFlows Counter32 } rohcChannelIndex OBJECT-TYPE SYNTAX RohcChannelIndex MAX-ACCESS not-accessible STATUS current DESCRIPTION "The locally arbitrary, but unique identifier associated with this channel. The value is expected to remain constant at least from one re-initialization of the entity's network management system to the next re-initialization." ::= { rohcChannelEntry 2 } rohcChannelMaxCID OBJECT-TYPE SYNTAX Integer32 (1..2147483647) MAX-ACCESS read-only STATUS current DESCRIPTION "The highest context ID number to be used by the compressor as defined in RFC 3095, Section 5.1.1. Note that this parameter is not coupled to, but in effect further constrained by, rohcChannelLargeCIDs." ::= { rohcChannelEntry 3 } rohcChannelLargeCIDs OBJECT-TYPE SYNTAX TruthValue MAX-ACCESS read-only STATUS current DESCRIPTION "Boolean, as defined by RFC 3095, Section 5.1.1: if false, the short CID representation (0 bytes or 1 prefix byte, covering CID 0 to 15) is used; if true, the embedded CID Quittek, Hartenstein, Stiemerling [Page 11]
Internet-Draft ROHC MIB November 2001 representation (1 or 2 embedded CID bytes covering CID 0 to 16383) is used." ::= { rohcChannelEntry 4 } rohcChannelFeedbackFor OBJECT-TYPE SYNTAX RohcChannelIndex MAX-ACCESS read-only STATUS current DESCRIPTION "The index of another channel of this interface for which the channel serves as feedback channel, see RFC 3095, Section 5.1.1." ::= { rohcChannelEntry 5 } rohcChannelMRRU OBJECT-TYPE SYNTAX Integer32 (1..2147483647) MAX-ACCESS read-only STATUS current DESCRIPTION "Maximum reconstructed reception unit according to RFC 3095, Section 5.1.1. This is the size of the largest reconstructed unit in octets that the decompressor is expected to reassemble from segments (see RFC 3095, Section 5.2.5). Note that this size includes the CRC. If MRRU is negotiated to be 0, no segment headers are allowed on the channel." ::= { rohcChannelEntry 6 } rohcChannelCompressedFlows OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "counter of outgoing flows having used ROHC on this channel." ::= { rohcChannelEntry 7 } rohcChannelDecompressedFlows OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "counter of incoming flows having used ROHC on this channel." ::= { rohcChannelEntry 8 } -- -- Profile Table -- rohcProfileTable OBJECT-TYPE SYNTAX SEQUENCE OF RohcProfileEntry Quittek, Hartenstein, Stiemerling [Page 12]
Internet-Draft ROHC MIB November 2001 MAX-ACCESS not-accessible STATUS current DESCRIPTION "This table lists a set of nonnegative integers as defined in RFC 3095, Section 5.1.1. Each integer indicates a profile supported by the decompressor. The compressor MUST NOT compress using a profile not in this list." ::= { rohcChannelObjects 2 } rohcProfileEntry OBJECT-TYPE SYNTAX RohcProfileEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "An entry describing a particular profile supported by the decompressor. " INDEX { ifIndex, rohcChannelIndex, rohcProfile } ::= { rohcProfileTable 1 } RohcProfileEntry ::= SEQUENCE { rohcProfile Integer32 } rohcProfile OBJECT-TYPE SYNTAX Integer32 (0..2147483647) MAX-ACCESS read-only STATUS current DESCRIPTION "Identifier of a profile supported by the decompressor, as defined in RFC 3095, Section 5.1.1." ::= { rohcProfileEntry 3 } -- -- Compressor contexts -- -- This group defines three tables: -- 1. The rohcCompressorTable lists all compressor contexts per channel -- and interface. -- 2. The rohcPacketSizeTable lists all allowed packet sizes per -- compressor context, channel, and interface. Used packet sizes are -- marked. -- 3. The rohcPayloadSizeTable lists all payload sizes that can be -- expected. -- rohcCompressorObjects OBJECT IDENTIFIER ::= { rohcObjects 4 } rohcCompressorTable OBJECT-TYPE SYNTAX SEQUENCE OF RohcCompressorEntry MAX-ACCESS not-accessible Quittek, Hartenstein, Stiemerling [Page 13]
Internet-Draft ROHC MIB November 2001 STATUS current DESCRIPTION "This table lists and describes all compressor contexts per channel and interface." ::= { rohcCompressorObjects 1 } rohcCompressorEntry OBJECT-TYPE SYNTAX RohcCompressorEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "An entry describing a particular compressor context." INDEX { ifIndex, rohcChannelIndex, rohcCompressorCID } ::= { rohcCompressorTable 1 } RohcCompressorEntry ::= SEQUENCE { rohcCompressorCID Integer32, rohcCompressorState INTEGER, rohcCompressorMode INTEGER, rohcCompressorProfile Integer32, rohcCompressorReinit TruthValue, rohcCompressorSizesAllowed Integer32, rohcCompressorSizesUsed Integer32, rohcCompressorTotalRatio Integer32, rohcCompressorCurrentRatio Integer32, rohcCompressorOutPackets Counter32, rohcCompressorInACKs Counter32, rohcCompressorInNACKs Counter32, rohcCompressorInSNACKs Counter32 } rohcCompressorCID OBJECT-TYPE SYNTAX Integer32 (0..2147483647) MAX-ACCESS not-accessible STATUS current DESCRIPTION "The context identifier (CID) of this compressor context as defined in RFC 3095, Section 5.1.3." ::= { rohcCompressorEntry 3 } rohcCompressorState OBJECT-TYPE SYNTAX INTEGER { ir(1), fo(2), so(3) } MAX-ACCESS read-only STATUS current DESCRIPTION "State of the compressor context as defined in RFC 3095, Quittek, Hartenstein, Stiemerling [Page 14]
Internet-Draft ROHC MIB November 2001 Section 4.3.1." ::= { rohcCompressorEntry 4 } rohcCompressorMode OBJECT-TYPE SYNTAX INTEGER { u(1), o(2), r(3) } MAX-ACCESS read-only STATUS current DESCRIPTION "Mode of the compressor context as defined in RFC 3095, Section 4.4." ::= { rohcCompressorEntry 5 } rohcCompressorProfile OBJECT-TYPE SYNTAX Integer32 (0..2147483647) MAX-ACCESS read-only STATUS current DESCRIPTION "Identifier of the profile for this compressor context. The profile is identified by its index in the rohcProfileTable for this channel." ::= { rohcCompressorEntry 6 } rohcCompressorReinit OBJECT-TYPE SYNTAX TruthValue MAX-ACCESS read-write STATUS current DESCRIPTION "By setting this object to true(1), a context reinitialization is triggered. When retrieved, the value of this object will always be false(2)." ::= { rohcCompressorEntry 7 } rohcCompressorSizesAllowed OBJECT-TYPE SYNTAX Integer32 (1..2147483647) MAX-ACCESS read-only STATUS current DESCRIPTION "Number of different packet sizes the compressor may use, as defined in RFC 3095, Section 6.3.1." ::= { rohcCompressorEntry 8 } rohcCompressorSizesUsed OBJECT-TYPE SYNTAX Integer32 (1..2147483647) MAX-ACCESS read-only Quittek, Hartenstein, Stiemerling [Page 15]
Internet-Draft ROHC MIB November 2001 STATUS current DESCRIPTION "Number of different packet sizes the compressor uses, as defined in RFC 3095, Section 6.3.1." ::= { rohcCompressorEntry 9 } -- The remaining elements of the rohcCompressorEntry defined -- below belong to the statistics group. rohcCompressorTotalRatio OBJECT-TYPE SYNTAX Integer32 (0..1000) MAX-ACCESS read-only STATUS current DESCRIPTION "This object indicates the compression ratio so far of the entire flow mapped to this compressor context. The value is defined as 1000 * bytes(compressed) / bytes(original) rounded to the next integer value." ::= { rohcCompressorEntry 10 } rohcCompressorCurrentRatio OBJECT-TYPE SYNTAX Integer32 (0..1000) MAX-ACCESS read-only STATUS current DESCRIPTION "This object indicates the compression ratio of the flow mapped to this compressor context concerning the last 16 packets or concerning all packets if they are less than 16, so far. The value is defined as 1000 * bytes(compressed) / bytes(original) rounded to the next integer value." ::= { rohcCompressorEntry 11 } rohcCompressorOutPackets OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The number of all packets sent so far in this compressor context." ::= { rohcCompressorEntry 12 } rohcCompressorInACKs OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The number of all received positive feedbacks (ACK) from the decompressor in this compressor context, as defined by RFC 3095, Section 5.2.1." Quittek, Hartenstein, Stiemerling [Page 16]
Internet-Draft ROHC MIB November 2001 ::= { rohcCompressorEntry 13 } rohcCompressorInNACKs OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The number of all received dynamic negative feedbacks (NACK) from the decompressor in this compressor context, as defined by RFC 3095, Section 5.2.1." ::= { rohcCompressorEntry 14 } rohcCompressorInSNACKs OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The number of all received static negative feedbacks (STATIC-NACK) from the decompressor in this compressor context, as defined by RFC 3095, Section 5.2.1." ::= { rohcCompressorEntry 15 } -- -- Packet Sizes Table -- rohcPacketSizeTable OBJECT-TYPE SYNTAX SEQUENCE OF RohcPacketSizeEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "This table lists all allowed packet sizes per comprssor context, channel, and interface. Used packet sizes are marked." ::= { rohcCompressorObjects 2 } rohcPacketSizeEntry OBJECT-TYPE SYNTAX RohcPacketSizeEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "An entry of a particular allowed packet size." INDEX { ifIndex, rohcChannelIndex, rohcCompressorCID, rohcPacketSize } ::= { rohcPacketSizeTable 1 } RohcPacketSizeEntry ::= SEQUENCE { rohcPacketSize Integer32, rohcPacketSizeUsed TruthValue } Quittek, Hartenstein, Stiemerling [Page 17]
Internet-Draft ROHC MIB November 2001 rohcPacketSize OBJECT-TYPE SYNTAX Integer32 (0..2147483647) MAX-ACCESS not-accessible STATUS current DESCRIPTION "A packet size used as index." ::= { rohcPacketSizeEntry 4 } rohcPacketSizeUsed OBJECT-TYPE SYNTAX TruthValue MAX-ACCESS read-only STATUS current DESCRIPTION "When retrieved, this object will have the value true(1) if the packet size is used by the compressor context. Otherwise its value will be false(2), see RFC 3095, Section 6.3.1." ::= { rohcPacketSizeEntry 5 } -- -- Payload Sizes Table -- rohcPayloadSizeTable OBJECT-TYPE SYNTAX SEQUENCE OF RohcPayloadSizeEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "This table lists all payload sizes that can be expected as described in RFC 3095, Section 6.3.1." ::= { rohcCompressorObjects 3 } rohcPayloadSizeEntry OBJECT-TYPE SYNTAX RohcPayloadSizeEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "An entry of a particular payload size." INDEX { ifIndex, rohcChannelIndex, rohcCompressorCID, rohcPayloadSize } ::= { rohcPayloadSizeTable 1 } RohcPayloadSizeEntry ::= SEQUENCE { rohcPayloadSize Integer32 } rohcPayloadSize OBJECT-TYPE SYNTAX Integer32 (0..2147483647) MAX-ACCESS read-only STATUS current DESCRIPTION Quittek, Hartenstein, Stiemerling [Page 18]
Internet-Draft ROHC MIB November 2001 "A payload size used as index." ::= { rohcPayloadSizeEntry 4 } -- -- Decompressor contexts -- -- This group defines a table which lists all decompressor contexts -- per channel and interface. -- rohcDecompressorTable OBJECT-TYPE SYNTAX SEQUENCE OF RohcDecompressorEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "This table lists and describes all decompressor contexts per channel and interface." ::= { rohcObjects 5 } rohcDecompressorEntry OBJECT-TYPE SYNTAX RohcDecompressorEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "An entry describing a particular decompressor context." INDEX { ifIndex, rohcChannelIndex, rohcDecompressorCID } ::= { rohcDecompressorTable 1 } RohcDecompressorEntry ::= SEQUENCE { rohcDecompressorCID Integer32, rohcDecompressorState INTEGER, rohcDecompressorMode INTEGER, rohcDecompressorProfile Integer32, rohcDecompressorDepth Integer32, rohcDecompressorInPackets Counter32, rohcDecompressorOutACKs Counter32, rohcDecompressorOutNACKs Counter32, rohcDecompressorOutSNACKs Counter32 } rohcDecompressorCID OBJECT-TYPE SYNTAX Integer32 (0..2147483647) MAX-ACCESS not-accessible STATUS current DESCRIPTION "The context identifier (CID) of this decompressor context as defined in RFC 3095, Section 5.1.3." ::= { rohcDecompressorEntry 3 } rohcDecompressorState OBJECT-TYPE Quittek, Hartenstein, Stiemerling [Page 19]
Internet-Draft ROHC MIB November 2001 SYNTAX INTEGER { ir(1), fo(2), so(3) } MAX-ACCESS read-only STATUS current DESCRIPTION "State of the decompressor context as defined in RFC 3095, Section 4.3.1." ::= { rohcDecompressorEntry 4 } rohcDecompressorMode OBJECT-TYPE SYNTAX INTEGER { u(1), o(2), r(3) } MAX-ACCESS read-only STATUS current DESCRIPTION "Mode of the decompressor context as defined in RFC 3095, Section 4.4." ::= { rohcDecompressorEntry 5 } rohcDecompressorProfile OBJECT-TYPE SYNTAX Integer32 (0..2147483647) MAX-ACCESS read-only STATUS current DESCRIPTION "Identifier of the profile for this decompressor context. The profile is identified by its index in the rohcProfileTable for this channel." ::= { rohcDecompressorEntry 6 } rohcDecompressorDepth OBJECT-TYPE SYNTAX Integer32 (0..2147483647) MAX-ACCESS read-only STATUS current DESCRIPTION "This object indicates whether reverse decompression as described in RFC 3095, Section 6.1 should be used or not, and if used, to what extent. For more details see RFC 3095, Section 6.3.2." ::= { rohcDecompressorEntry 7 } -- The remaining elements of the rohcDecompressorEntry defined -- below belong to the statistics group. rohcDecompressorInPackets OBJECT-TYPE Quittek, Hartenstein, Stiemerling [Page 20]
Internet-Draft ROHC MIB November 2001 SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The number of all packets sent so far in this decompressor context." ::= { rohcDecompressorEntry 8 } rohcDecompressorOutACKs OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The number of all sent positive feedbacks (ACK) from this decompressor context, as defined by RFC 3095, Section 5.2.1." ::= { rohcDecompressorEntry 9 } rohcDecompressorOutNACKs OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The number of all sent dynamic negative feedbacks (NACK) from this decompressor context, as defined by RFC 3095, Section 5.2.1." ::= { rohcDecompressorEntry 10 } rohcDecompressorOutSNACKs OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The number of all rsent static negative feedbacks (STATIC-NACK) from the decompressor context, as defined by RFC 3095, Section 5.2.1." ::= { rohcDecompressorEntry 11 } -- -- Statistics Group -- -- This group consists of two tables providing packet statistis -- information and some statisitics related elements of the compressors -- table and the decompressor table. -- rohcStatisticsObjects OBJECT IDENTIFIER ::= { rohcObjects 6 } -- -- Sent Packet Counter Table Quittek, Hartenstein, Stiemerling [Page 21]
Internet-Draft ROHC MIB November 2001 -- rohcOutPacketCounterTable OBJECT-TYPE SYNTAX SEQUENCE OF RohcOutPacketCounterEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "This table lists packet counters per header type, compressor context, channel and interface." ::= { rohcStatisticsObjects 1 } rohcOutPacketCounterEntry OBJECT-TYPE SYNTAX RohcOutPacketCounterEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "An entry of a particular sent packet counter." INDEX { ifIndex, rohcChannelIndex, rohcCompressorCID, rohcHeaderIndex } ::= { rohcOutPacketCounterTable 1 } RohcOutPacketCounterEntry ::= SEQUENCE { rohcOutPacketCounter Counter32 } rohcOutPacketCounter OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "A counter for sent packets of a particular header type." ::= { rohcOutPacketCounterEntry 5 } -- -- Received Packet Counter Table -- rohcInPacketCounterTable OBJECT-TYPE SYNTAX SEQUENCE OF RohcInPacketCounterEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "This table lists received packet counters per header type, compressor context, channel and interface." ::= { rohcStatisticsObjects 2 } rohcInPacketCounterEntry OBJECT-TYPE SYNTAX RohcInPacketCounterEntry MAX-ACCESS not-accessible STATUS current Quittek, Hartenstein, Stiemerling [Page 22]
Internet-Draft ROHC MIB November 2001 DESCRIPTION "An entry of a particular received packet counter." INDEX { ifIndex, rohcChannelIndex, rohcDecompressorCID, rohcHeaderIndex } ::= { rohcInPacketCounterTable 1 } RohcInPacketCounterEntry ::= SEQUENCE { rohcInPacketCounter Counter32 } rohcInPacketCounter OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "A counter for received packets of a particular header type." ::= { rohcInPacketCounterEntry 5 } -- -- CRC Error Counter Table -- rohcErrorTable OBJECT-TYPE SYNTAX SEQUENCE OF RohcErrorEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "This table lists error counters per error type, compressor context, channel and interface. Since error types are not uniquely defined in RFC 3095, Each error type contains next to the error counter a textual description of the type." ::= { rohcStatisticsObjects 3 } rohcErrorEntry OBJECT-TYPE SYNTAX RohcErrorEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "An entry of a particular received packet counter." INDEX { ifIndex, rohcChannelIndex, rohcDecompressorCID, rohcErrorIndex } ::= { rohcErrorTable 1 } RohcErrorEntry ::= SEQUENCE { rohcErrorIndex Integer32, rohcErrorDescr SnmpAdminString, rohcErrorCounter Counter32 } rohcErrorIndex OBJECT-TYPE Quittek, Hartenstein, Stiemerling [Page 23]
Internet-Draft ROHC MIB November 2001 SYNTAX Integer32 (1..2147483647) MAX-ACCESS not-accessible STATUS current DESCRIPTION "The locally arbitrary, but unique identifier associated with this error type. The value is expected to remain constant at least from one re-initialization of the entity's network management system to the next re-initialization." ::= { rohcErrorEntry 4 } rohcErrorDescr OBJECT-TYPE SYNTAX SnmpAdminString MAX-ACCESS read-only STATUS current DESCRIPTION "A textual description of the error type." ::= { rohcErrorEntry 5 } rohcErrorCounter OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "A counter for occurrences of this error type." ::= { rohcErrorEntry 6 } -- -- conformance information -- rohcCompliances OBJECT IDENTIFIER ::= { rohcConformance 1 } rohcGroups OBJECT IDENTIFIER ::= { rohcConformance 2 } -- -- compliance statements -- rohcCompliance MODULE-COMPLIANCE STATUS current DESCRIPTION "The compliance statement for SNMP entities which implement the ROHC MIB." MODULE -- this module MANDATORY-GROUPS { rohcIfGroup, rohcHeaderGroup, rohcChannelGroup, rohcCompressorGroup, rohcDecompressorGroup Quittek, Hartenstein, Stiemerling [Page 24]
Internet-Draft ROHC MIB November 2001 } GROUP rohcStatisticsGroup DESCRIPTION "A compliant implementation does not have to implement the rohcStatisticsGroup." OBJECT rohcCompressorReinit MIN-ACCESS not-accessible DESCRIPTION "A compliant implementation does not have to support re-initialization of contexts initiated via this SNMP." ::= { rohcCompliances 1 } rohcIfGroup OBJECT-GROUP OBJECTS { rohcIfVendor, rohcIfVersion, rohcIfDescr, rohcIfClockRes, rohcIfStatus } STATUS current DESCRIPTION "A collection of objects providing information about the network interfaces supporting ROHC." ::= { rohcGroups 1 } rohcHeaderGroup OBJECT-GROUP OBJECTS { rohcHeaderString, rohcHeaderDescr } STATUS current DESCRIPTION "A collection of objects providing information about supported ROHC headers." ::= { rohcGroups 2 } rohcChannelGroup OBJECT-GROUP OBJECTS { rohcChannelMaxCID, rohcChannelLargeCIDs, rohcChannelFeedbackFor, rohcChannelMRRU, rohcChannelCompressedFlows, rohcChannelDecompressedFlows, rohcProfile } STATUS current DESCRIPTION "A collection of objects providing information about Quittek, Hartenstein, Stiemerling [Page 25]
Internet-Draft ROHC MIB November 2001 supported ROHC headers." ::= { rohcGroups 3 } rohcCompressorGroup OBJECT-GROUP OBJECTS { rohcCompressorState, rohcCompressorMode, rohcCompressorProfile, rohcCompressorReinit, rohcCompressorSizesAllowed, rohcCompressorSizesUsed, rohcPacketSizeUsed, rohcPayloadSize } STATUS current DESCRIPTION "A collection of objects providing information about supported ROHC headers." ::= { rohcGroups 4 } rohcDecompressorGroup OBJECT-GROUP OBJECTS { rohcDecompressorState, rohcDecompressorMode, rohcDecompressorProfile, rohcDecompressorDepth } STATUS current DESCRIPTION "A collection of objects providing information about supported ROHC headers." ::= { rohcGroups 6 } rohcStatisticsGroup OBJECT-GROUP OBJECTS { rohcCompressorTotalRatio, rohcCompressorCurrentRatio, rohcCompressorOutPackets, rohcCompressorInACKs, rohcCompressorInNACKs, rohcCompressorInSNACKs, rohcDecompressorInPackets, rohcDecompressorOutACKs, rohcDecompressorOutNACKs, rohcDecompressorOutSNACKs, rohcOutPacketCounter, rohcInPacketCounter, rohcErrorDescr, rohcErrorCounter } Quittek, Hartenstein, Stiemerling [Page 26]
Internet-Draft ROHC MIB November 2001 STATUS current DESCRIPTION "A collection of objects providing information about supported ROHC headers." ::= { rohcGroups 7 } END 6. Security Considerations The managed objects defined by the ROHC MIB are read-only with just one exception, the rohcCompressorReinit object. Therefore, unauthorized users getting access to the MIB via SNMP cannot cause harm to existing ROHC connections nor can they manipulate running instances of ROHC in a malicious way. The only effect they could achieve is reinitializing compressor contexts unnecessarily and thereby downgrading the performance. Another security issue is mis-use of he MIB for getting information about existing communication sessions. However, the only information that might be disclosed is the use of channels. Users and their addresses are not visible in the MIB. This information can only be mis-used in conjunction with the mis-use of further information. Although, the security risks arising from the ROHC MIB are not considered to be high, it is recommended for implementors and operators to apply the means for security offered by SNMPv3, particularly encryption of communication and the User-based Security Model described in [RFC2574]. 7. References [RFC3095] Bormann, C., et al. "An RObust Header Compression (ROHC): Framework and four profiles: RTP, UDP, ESP, and uncompressed ", RFC 3095, July 2001. [RFC2571] Harrington, D., Presuhn, R., and B. Wijnen, "An Architecture for Describing SNMP Management Frameworks", RFC 2571, April 1999. [RFC1155] Rose, M., and K. McCloghrie, "Structure and Identification of Management Information for TCP/IP-based Internets", STD 16, RFC 1155, May 1990. [RFC1212] Rose, M., and K. McCloghrie, "Concise MIB Definitions", STD 16, RFC 1212, March 1991. Quittek, Hartenstein, Stiemerling [Page 27]
Internet-Draft ROHC MIB November 2001 [RFC1215] M. Rose, "A Convention for Defining Traps for use with the SNMP", RFC 1215, March 1991. [RFC2578] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J., Rose, M., and S. Waldbusser, "Structure of Management Information Version 2 (SMIv2)", STD 58, RFC 2578, April 1999. [RFC2579] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J., Rose, M., and S. Waldbusser, "Textual Conventions for SMIv2", STD 58, RFC 2579, April 1999. [RFC2580] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J., Rose, M., and S. Waldbusser, "Conformance Statements for SMIv2", STD 58, RFC 2580, April 1999. [RFC1157] Case, J., Fedor, M., Schoffstall, M., and J. Davin, "Simple Network Management Protocol", STD 15, RFC 1157, May 1990. [RFC1901] Case, J., McCloghrie, K., Rose, M., and S. Waldbusser, "Introduction to Community-based SNMPv2", RFC 1901, January 1996. [RFC1906] Case, J., McCloghrie, K., Rose, M., and S. Waldbusser, "Transport Mappings for Version 2 of the Simple Network Management Protocol (SNMPv2)", RFC 1906, January 1996. [RFC2572] Case, J., Harrington D., Presuhn R., and B. Wijnen, "Message Processing and Dispatching for the Simple Network Management Protocol (SNMP)", RFC 2572, April 1999. [RFC2574] Blumenthal, U., and B. Wijnen, "User-based Security Model (USM) for version 3 of the Simple Network Management Protocol (SNMPv3)", RFC 2574, April 1999. [RFC1905] Case, J., McCloghrie, K., Rose, M., and S. Waldbusser, "Protocol Operations for Version 2 of the Simple Network Management Protocol (SNMPv2)", RFC 1905, January 1996. [RFC2573] Levi, D., Meyer, P., and B. Stewart, "SNMPv3 Applications", RFC 2573, April 1999. [RFC2575] Wijnen, B., Presuhn, R., and K. McCloghrie, "View-based Access Control Model (VACM) for the Simple Network Management Protocol (SNMP)", RFC 2575, April 1999. [RFC2570] Case, J., Mundy, R., Partain, D., and B. Stewart, "Introduction to Version 3 of the Internet-standard Network Management Framework", RFC 2570, April 1999. Quittek, Hartenstein, Stiemerling [Page 28]
Internet-Draft ROHC MIB November 2001 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", RFC 2119, March 1997. 8. Authors' Addresses Juergen Quittek NEC Europe Ltd. Network Laboratories Adenauerplatz 6 69115 Heidelberg Germany Phone: +49 6221 90511-15 EMail: quittek@ccrle.nec.de Hannes Hartenstein NEC Europe Ltd. Network Laboratories Adenauerplatz 6 69115 Heidelberg Germany Phone: +49 6221 13708-14 Email: hannes.hartenstein@ccrle.nec.de Martin Stiemerling NEC Europe Ltd. Network Laboratories Adenauerplatz 6 69115 Heidelberg Germany Phone: +49 6221 90511-13 Email: stiemerling@ccrle.nec.de Quittek, Hartenstein, Stiemerling [Page 29]
Internet-Draft ROHC MIB November 2001 9. Full Copyright Statement Copyright (C) The Internet Society (2001). All Rights Reserved. This document and translations of it may be copied and furnished to others, and derivative works that comment on or otherwise explain it or assist in its implementation may be prepared, copied, published and distributed, in whole or in part, without restriction of any kind, provided that the above copyright notice and this paragraph are included on all such copies and derivative works. However, this document itself may not be modified in any way, such as by removing the copyright notice or references to the Internet Society or other Internet organizations, except as needed for the purpose of developing Internet standards in which case the procedures for copyrights defined in the Internet Standards process must be followed, or as required to translate it into languages other than English. The limited permissions granted above are perpetual and will not be revoked by the Internet Society or its successors or assigns. This document and the information contained herein is provided on an "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Quittek, Hartenstein, Stiemerling [Page 30]
