rtgwg S. Hu
Internet-Draft China Mobile
Intended status: Informational Z. Wang
Expires: January 1, 2019 Huawei
F. Qin
Z. Li
China Mobile
J. Song
Huawei
June 30, 2018
Control-Plane and User-Plane separation BNG control channel Protocol
draft-cuspdt-rtgwg-cu-separation-bng-protocol-00
Abstract
This document specifies the CU Separation BNG control channel
Protocol (CUSP) for communications between a Control Plane (CP) and a
set of User Planes (UPs). CUSP is designed to be flexible and
extensible so as to easily allow for the addition of further messages
and objects, should further requirements be expressed in the future.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
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This Internet-Draft will expire on January 1, 2019.
Copyright Notice
Copyright (c) 2018 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
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publication of this document. Please review these documents
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Concept and Terminology . . . . . . . . . . . . . . . . . . . 3
2.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3
3. Protocol Overview . . . . . . . . . . . . . . . . . . . . . . 3
3.1. Initialization Phase . . . . . . . . . . . . . . . . . . 3
3.2. Network Resource Report . . . . . . . . . . . . . . . . . 4
3.3. IPoE Session Establishment . . . . . . . . . . . . . . . 5
3.4. PPPoE Session Establishment . . . . . . . . . . . . . . . 7
3.5. Set User's QoS Information . . . . . . . . . . . . . . . 8
3.6. CUSP session statistic . . . . . . . . . . . . . . . . . 9
4. CUSP common header . . . . . . . . . . . . . . . . . . . . . 9
5. Objective Message Formats . . . . . . . . . . . . . . . . . . 10
5.1. Objective TLV Format . . . . . . . . . . . . . . . . . . 11
6. Control Message Format . . . . . . . . . . . . . . . . . . . 12
6.1. Control TLV Format . . . . . . . . . . . . . . . . . . . 12
6.2. Hello Message . . . . . . . . . . . . . . . . . . . . . . 13
6.3. Smooth Message . . . . . . . . . . . . . . . . . . . . . 13
7. Event TLV Format . . . . . . . . . . . . . . . . . . . . . . 14
7.1. Event TLV Format . . . . . . . . . . . . . . . . . . . . 15
7.2. USER_TRAFFIC_INFORMATION Message . . . . . . . . . . . . 15
7.3. USER_DETECT_RESULT_ INFORMATION Message . . . . . . . . . 16
8. Resource Report TLV Format . . . . . . . . . . . . . . . . . 16
8.1. Resource Report TLV Format . . . . . . . . . . . . . . . 17
9. Error Message Format . . . . . . . . . . . . . . . . . . . . 17
10. Security Considerations . . . . . . . . . . . . . . . . . . . 18
11. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 18
12. Normative References . . . . . . . . . . . . . . . . . . . . 18
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 19
1. Introduction
BNG is an Ethernet-centric IP edge router, and the aggregation point
for the user traffic. To provide centralized session management,
flexible address allocation, high scalability for subscriber
management capacity, and cost-efficient redundancy, the CU separated
BNG is introduced [TR-384]. The CU separated Service Control Plane
could be virtualized and centralized, which is responsible for user
access authentication and setting forwarding entries to user planes.
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The routing control and forwarding plane, i.e. BNG user plane
(local), could be distributed across the infrastructure.
This document specifies the CU Separation BNG control channel
Protocol (CUSP) for communications between a Control Plane (CP) and a
set of User Planes (UPs). CUSP is designed to be flexible and
extensible so as to easily allow for the addition of further messages
and objects, should further requirements be expressed in the future.
2. Concept and Terminology
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 [RFC2119].
2.1. Terminology
BNG: Broadband Network Gateway. A broadband remote access server
(BRAS, B-RAS or BBRAS) routes traffic to and from broadband remote
access devices such as digital subscriber line access multiplexers
(DSLAM) on an Internet service provider's (ISP) network. BRAS can
also be referred to as a Broadband Network Gateway (BNG).
CP: Control Plane. CP is a user control management component which
supports the management of UP's resources such as the user entry and
forwarding policy
UP: User Plane. UP is a network edge and user policy implementation
component. The traditional router's Control Plane and Forwarding
Plane are both preserved on BNG devices in the form of a user plane.
3. Protocol Overview
3.1. Initialization Phase
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UP CP
| |
| |
| |
| HELLO (version) |
|------------------------------>|
| |
| |
| |
| HELLO (version) |
|<----------------------------- |
| |
| |
| |
The initialization phase consists of two successive steps:
1) Establishment of a TCP connection (3-way handshake) between the CP
and the UP.
2) Establishment of a CUSP session over the TCP connection.
Once the TCP connection is established, the CP and the UP initiate
CUSP session establishment during which the version negotiation are
performed. The version's information are carried within Hello
messages. If the CUSP session establishment phase fails because the
CP or UP disagree on the version parameters or one of the CP or UP
does not answer after the expiration of the establishment timer, the
TCP connection is immediately closed.
Details about the Hello message can be found in Sections 6.2
respectively.
3.2. Network Resource Report
The CP configures the BNG's access interface via NETCONF, and UPs
report attributes of according interfaces and slots.
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UP CP
| |
| slot attributes report |
|------------------------------>|
| |
| port attributes report |
|------------------------------>|
| Configure BNG access |
|<-------interface via netconf->|
| |
| |
| |
Details about the Resource Report Message can be found in Sections 8
respectively.
3.3. IPoE Session Establishment
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UP CP
| UP report the resources |
|----via CUSP------------------>|
| |
| Configur BNG access |
|<--------interface via netconf-|
| |
| CP sends ACCESS_IF_INFO |
|<---to UPs via CUSP------------|
| |
| User dialup via VXLAN |
|<----------------------------->|
| |
| CP sends USER_BASEC_INFO |
|<---to UPs via CUSP------------|
| |
| CP sends USER_IPV4_INFO |
|<---to UPs via CUSP------------|
| |
| CP sends ROUTEV4 INFO |
|<---to UPs via CUSP------------|
| |
| UP report the USER_DETECT_RESULT_INFO
|----to CP via CUSP------------>|
| |
| |
| UP report the USER_TRAFFIC_INFO
|----to CP via CUSP------------>|
| |
Once a CUSP session has been established, if an IPoE session be
required that the UPs report attributes of corresponding interfaces
and slots via CUSP, and the CP initiate a NETCONF session to
configure requested access interface of BNG.
Once above process has been accomplished, the CP sends the
ACCESS_IF_INFO (Access Interface Information) message to UPs that
contains a variety of objects that specify the set of constrains and
attributes for the BNG access interface. For example, ifname = 0001,
BNG service enable, IPv4 connection trigger enable, neighbor
detection enable, etc.
And then the user dialup via VXLAN, the CP sends the USER_BASIC_INFOR
message USER_IPV4_INFOR, and USER_ROUTEV4_INFO to UPs that contains a
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variety of objects that specify the attributes for the user's basic
information, user's ipv4 information, and routing information.
Upon receiving above messages from a CP, the UPs reports the user
detection results and user's traffic status via
USER_DETECT_RESULT_INFO message and USER_TRAFFIC_INFO, etc.
3.4. PPPoE Session Establishment
UP CP
| |
| UP report the resources |
|----via CUSP------------------>|
| Configur BNG access |
|<-------interface via netconf->|
| |
| CP sends ACCESS_IF_INFO |
|<---to UPs via CUSP------------|
| |
| User dialup via VXLAN |
|<----------------------------->|
| |
| CP sends USER_BASEC_INFO |
|<---to UPs via CUSP------------|
| |
| CP sends USER_IPV4_INFO |
|<---to UPs via CUSP------------|
| |
| CP sends ROUTEV4 INFO |
|<---to UPs via CUSP------------|
| |
| CP sends USER_PPP_INFO |
|<---to UPs via CUSP------------|
| |
| UP report the USER_DETECT_RESULT_INFO
|----to CP via CUSP------------>|
| |
| UP report the USER_TRAFFIC_INFO
|----to CP via CUSP------------>|
| |
Once a CUSP session has been established, if an PPPoE session be
required that the UPs report attributes of corresponding interfaces
and slots via CUSP, and the CP initiate a NETCONF session to
configure requested access interface of BNG.
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Once above process has been accomplished, the CP sends the
ACCESS_IF_INFO (Access Interface Information) message to UPs that
contains a variety of objects that specify the set of constrains and
attributes for the BNG access interface. For example, ifname = 0001,
BNG service enable, IPv4 connection trigger enable, neighbor
detection enable, etc.
And then the user dialup via VXLAN, the CP sends the USER_BASIC_INFOR
message, USER_PPP_INFO message, USER_IPV4_INFOR message, and
USER_ROUTEV4_INFO message to UPs that contains a variety of objects
that specify the attributes for the user's basic information, user's
PPP information, user's ipv4 information, and routing information.
Upon receiving above messages from a CP, the UPs reports the user
detection results and user's traffic status via
USER_DETECT_RESULT_INFO message and USER_TRAFFIC_INFO, etc.
3.5. Set User's QoS Information
UP CP
| |
| UP report the resources |
|----via CUSP------------------>|
| |
| Configure BNG Access interface
|<-----via netconf--------------|
| |
| Configure QOS template |
|<-----via netconf--------------|
| |
| User dialup via VXLAN/ |
|<---CP sends objecitve tlv/event
| report,etc. |
| |
| CP sends USER_QOS_INFO |
|<---to UPs via CUSP------------|
| |
Once a CUSP session has been established, if a user's QoS needs to be
set dynamically that the UPs report attributes of according
interfaces and slots via CUSP, and the CP initiate a NETCONF session
to configure requested access interface of BNG and User's
configuration template. And then the user dialup via VXLAN, the CP
sends the USER_BASIC_INFOR message, USER_IPV4_INFOR message, and
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USER_ROUTEV4_INFO message to UP, the UPs reports the user detection
results and user's traffic status.
Once above process has been accomplished, the CP sends the
USER_QOS_AUTH_INFO message to UPs that contains a variety of objects
that specify the set of constrains and attributes for the user's
required QoS.(Note that the format of these QoS attributes should
synchronize with QoS configuration templates.)
3.6. CUSP session statistic
UP CP
| |
| |
|<-----statistic REQUEST ------------|
| |
|------statistic_REQUEST (ACK)------>|
| |
|------statistic_BEGIN-------------->|
| |
|<-----statistic_BEGIN (ACK)---------|
| |
|------statistic_DATA--------------->|
| |
|------statistic_END---------------->|
| |
|<-----statistic_END (ACK)-----------|
| |
| |
If the CUSP session down, the CU separation BNG required that the
users' information should be reserved. And if the CUSP session
restart, the CP may request the UP to report the previous session's
statistics to synchronize user information. Above figure describe
this process, and the details about the session statistic message can
be found in Sections 6.3 respectively.
4. CUSP common header
A CUSP message consists of a common header followed by a variable-
length body made of a set of objects. A CUSP message with a missing
mandatory object MUST trigger an Error message (see Section 5.6).
Conversely, if an object is optional, the object may or may not be
present.
Common header:
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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-Type |F| Resv | Message-Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Transaction id |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
CUSP Message Common Header
Message-Type (8 bits): The following message types are currently
defined:
Value Meaning
1 Update objective
2 Hello
3 Smooth Request
4 Smooth Begin
5 Smooth Data
6 Smooth End
7 Source Report
8 Event Report
9 Error
Flags (1 bits): The control message ACK mode be enabled by setting it
to one.
Resv (7 bits): Unassigned bits are considered as reserved. They MUST
be set to zero on transmission and MUST be ignored on receipt.
Message-Length (16 bits): total length of the CUSP message including
the common header, expressed in bytes.
5. Objective Message Formats
CUSP objects have a common format. They begin with a CUSP common
header (see Section 4). This is followed by object-specific fields
defined for each different object. The object may also include one
or more type-length-value (TLV) encoded data sets. Each TLV has the
same structure as described in Section 5.1.
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5.1. Objective TLV Format
A CUSP object may include a set of one or more optional TLVs. All
CUSP objective TLVs have the following format:
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 | Message-Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Value |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type: 2 bytes
Length: 2 bytes
Value: variable
A CUSP object TLV is comprised of 2 bytes for the type, 2 bytes
specifying the TLV length, and a value field.
The first 4 bits of Type field indicate the operation of this TLV,
currently, there are two types: 0 - update the objectives; 1 - delete
the objectives.
The other bits of Type field indicate the TLV's type (4-15 bits), the
following message types are currently defined:
Value Meaning
0 USER_BASIC_INFO
1 USER_PPP_INFO
2 ACCESS_IFSRV_INFO
3 USER_IPV4_INFO
4 USER_IPV6_INFO
5 USER_QOS_AUTH_INFO
6 ROUTEV4_INFO
7 ROUTEV6_INFO
8 STATIC_USER_INFO
The Length field defines the length of the value portion in bytes.
The TLV is padded to 4-bytes alignment; padding is not included in
the Length field (so a 3-byte value would have a length of 3, but the
total size of the TLV would be 8 bytes).
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Unrecognized TLVs MUST be ignored.
IANA management of the CUSP Object TLV type identifier codespace is
described in Section 11.
The details about the attributes of Objective TLV are specified in
[Section 4.1 of draft-cuspdt-rtgwg-cu-separation-infor-model-00]
6. Control Message Format
CUSP Control TLV have a common format. They begin with a CUSP common
header (see Section 3). It is followed by control TLV fields defined
for each different control operations. It may also include one or
more type-length-value (TLV) encoded control data sets. Each TLV has
the same structure as described in Section 6.1.
For each CUSP message type, rules are defined that specify the set of
objects that the message can carry. We use the Backus-Naur Form
(BNF) (see [RBNF]) to specify such rules. Square brackets refer to
optional sub-sequences. An implementation MUST form the CUSP
messages using the object ordering specified in this document.
6.1. Control TLV Format
A CUSP control may include a set of one or more optional TLVs. All
CUSP control TLVs have the following format:
Type: 2 bytes
Length: 2 bytes
Value: variable
A CUSP control TLV is comprised of 2 bytes for the type, 2 bytes
specifying the TLV length, and a value field.
Control Type (8 bits): The following message types are currently
defined:
Value Meaning
0 Hello
1 Smooth
The Length field defines the length of the value portion in bytes.
The TLV is padded to 4-bytes alignment; padding is not included in
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the Length field (so a 3-byte value would have a length of 3, but the
total size of the TLV would be 8 bytes).
Unrecognized TLVs MUST be ignored.
IANA management of the CUSP Object TLV type identifier codespace is
described in Section 11.
6.2. Hello Message
The Hello message is a CUSP message sent by a UP to a CP and by a CP
to a UP in order to establish a CUSP session. The Type field of the
CUSP common header for the Hello message is set to 2.
Once the TCP connection has been successfully established, the first
message sent by the UP to the CP or by the CP to the UP MUST be a
Hello message.
Any message received prior to a Hello message MUST trigger a protocol
error condition causing an ERROR message to be sent with Error-Type
Version_ Negotiation_Failed and the CUSP session establishment
attempt MUST be terminated by closing the TCP connection.
The Hello message is used to establish a CUSP session between the
CUSP peers. During the establishment phase, the CUSP peers exchange
version information. If both parties agree on such version
negotiation, the CUSP session is successfully established.
The format of a Hello message is as follows:
<Hello Message>::= <Common Header>
<HELLO_TLV>
<Hello_TLV>:: = <version>
Version (4 bytes) : specifies the CP/UP supported CUSP's version,
currently, the version is 1.
6.3. Smooth Message
If the CUSP session down, the CU separation BNG required that the
users' information should be reserved. And if the CUSP session
restart, the CP may request the UP to report the previous session's
statistics to synchronize user information.
The Type field of the CUSP common header for the Smooth message is
set to 3/4/5/6.
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The format of a Smooth message is as follows:
<Hello Message>::= <Common Header>
<Smooth_TLV>
<Smooth_TLV>::= <ClassID><Event><Resv>
ClassID (2 bytes): specified the statistics type of CUS session, the
following statistics types are currently defined:
Value Meaning
0 objective message statistic
1 Source report message statistic
2 Event report message statistic
Event (2 bytes): specified the Smooth message's subtypes, the
following subtypes are currently defined:
Value Meaning
0 request smooth message
1 begin smooth message
2 Smooth data message
3 End smooth message
Note that, the event value MUST be synchronized with the type of
comment header.
7. Event TLV Format
CUSP Event TLV have a common format. They begin with a CUSP common
header (see Section 3). It is followed by Event TLV fields defined
for each different Events. It may also include one or more type-
length-value (TLV) encoded Event data sets. Each TLV has the same
structure as described in Section 7.1.
For each CUSP message type, rules are defined that specify the set of
objects that the message can carry. We use the Backus-Naur Form
(BNF) (see [RBNF]) to specify such rules. Square brackets refer to
optional sub-sequences. An implementation MUST form the CUSP
messages using the object ordering specified in this document.
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7.1. Event TLV Format
A CUSP Event may include a set of one or more optional TLVs. All
CUSP Event TLVs have the following format:
Type: 2 bytes
Length: 2 bytes
Value: variable
A CUSP Event TLV is comprised of 2 bytes for the type, 2 bytes
specifying the TLV length, and a value field.
Event Type (8 bits): The following message types are currently
defined:
Value Meaning
0 USER_TRAFFIC_INFORMATION
1 USER_DETECT_RESULT_ INFORMATION
The Length field defines the length of the value portion in bytes.
The TLV is padded to 4-bytes alignment; padding is not included in
the Length field (so a 3-byte value would have a length of 3, but the
total size of the TLV would be 8 bytes).
Unrecognized TLVs MUST be ignored.
IANA management of the CUSP Object TLV type identifier codespace is
described in Section 11.
7.2. USER_TRAFFIC_INFORMATION Message
The USER_TRAFFIC_INFORMATION Message be used to reported the user's
traffic statistics by UP.
The format of a USER_TRAFFIC_INFORMATION message is as follows:
<USER_TRAFFIC_INFORMATION Message>::= <Common Header>
<USER_TRAFFIC_INFORMATION_TLV>
<USER_TRAFFIC_INFORMATION _TLV>::= <UserId><StatisticsType>
<IngressPackets><IngressBytes>
<EngressPackets>< EgressBytes >
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USER_ID (4 bytes): is the identifier of user. This parameter is
unique and mandatory. This attribute is used to distinguish
different users.
StatisticsType (4 bytes): be used to indicate the Statistics type,
the following types are currently defined:
Value Meaning
0 IPv4 traffic statistic
1 IPv6 traffic statistic
IngressPackets (8 bytes): be used to present the ingress packets.
IngressBytes (8 bytes): be used to present the ingress bytes.
EgressPackets (8 bytes): be used to present the egress packets.
EgressBytes (8 bytes): be used to present the egress bytes.
7.3. USER_DETECT_RESULT_ INFORMATION Message
The USER_TRAFFIC_INFORMATION Message be used to reported the user
detect fail by UP.
The format of a USER_DETECT_RESULT_ INFORMATION message is as
follows:
< USER_DETECT_RESULT_ INFORMATION Message>::= <Common Header>
< USER_DETECT_RESULT_ INFORMATION _TLV>
< USER_DETECT_RESULT_ INFORMATION _TLV>::= <UserId><DetectFail>
USER_ID (4 bytes): is the identifier of user. This parameter is
unique and mandatory. This attribute is used to distinguish
different users.
DetectFail (2 bytes): be used to indicate that the user detect fail.
8. Resource Report TLV Format
CUSP Resource Report TLV have a common format. They begin with a
CUSP common header (see Section 3). It is followed by Event TLV
fields defined for each different Resources. It may also include one
or more type-length-value (TLV) encoded Resource Report data sets.
Each TLV has the same structure as described in Section 7.1.
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8.1. Resource Report TLV Format
A CUSP Resource Report may include a set of one or more optional
TLVs. All CUSP Resource Report TLVs have the following format:
Type: 2 bytes
Length: 2 bytes
Value: variable
A CUSP Resource Report TLV is comprised of 2 bytes for the type, 2
bytes specifying the TLV length, and a value field.
Resource Type (8 bits): The following message types are currently
defined:
Value Meaning
0 RESOURCE_IF_INFO
1 RESOURCE_SLOT_INFO
The Length field defines the length of the value portion in bytes.
The TLV is padded to 4-bytes alignment; padding is not included in
the Length field (so a 3-byte value would have a length of 3, but the
total size of the TLV would be 8 bytes).
Unrecognized TLVs MUST be ignored.
IANA management of the CUSP Object TLV type identifier codespace is
described in Section 11.
The details about the attributes of Resource Report TLV are specified
in [Section 4.2 of draft-cuspdt-rtgwg-cu-separation-infor-model-00]
9. Error Message Format
Error messages are used by the CP or UPs to notify the other side of
the connection of problems. They are mostly used by the UPs to
indicate a failure of a request initiated by the CP.
The format of an Error message is as follows:
<Err Message> ::= <Common Header>
<ERRID>
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ERRID (4 bytes): be used to indicate the error type, the following
types are currently defined:
Value Meaning
00~1000 Reserved
1001 version negotiation failed
1002 TLV type cannot be recognized
1003 TLV length Anomaly
1004 TLV objective Anomaly
1005 Smooth failed
1006 Smooth request not support
10. Security Considerations
None.
11. IANA Considerations
None.
12. Normative References
[I-D.cuspdt-rtgwg-cu-separation-bng-deployment]
Gu, R., Hu, S., and Z. Wang, "Deployment Model of Control
Plane and User Plane Separation BNG", draft-cuspdt-rtgwg-
cu-separation-bng-deployment-00 (work in progress),
October 2017.
[I-D.cuspdt-rtgwg-cu-separation-infor-model]
Wang, Z., Gu, R., Lopezalvarez, V., and S. Hu,
"Information Model of Control-Plane and User-Plane
separation BNG", draft-cuspdt-rtgwg-cu-separation-infor-
model-00 (work in progress), February 2018.
[I-D.cuspdt-rtgwg-cusp-requirements]
Hu, S., Gu, R., Lopezalvarez, V., Song, J., and Z. Wang,
"Requirements for Control Plane and User Plane Separated
BNG Protocol", draft-cuspdt-rtgwg-cusp-requirements-01
(work in progress), February 2018.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
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[RFC2863] McCloghrie, K. and F. Kastenholz, "The Interfaces Group
MIB", RFC 2863, DOI 10.17487/RFC2863, June 2000,
<https://www.rfc-editor.org/info/rfc2863>.
[RFC5511] Farrel, A., "Routing Backus-Naur Form (RBNF): A Syntax
Used to Form Encoding Rules in Various Routing Protocol
Specifications", RFC 5511, DOI 10.17487/RFC5511, April
2009, <https://www.rfc-editor.org/info/rfc5511>.
[RFC5837] Atlas, A., Ed., Bonica, R., Ed., Pignataro, C., Ed., Shen,
N., and JR. Rivers, "Extending ICMP for Interface and
Next-Hop Identification", RFC 5837, DOI 10.17487/RFC5837,
April 2010, <https://www.rfc-editor.org/info/rfc5837>.
Authors' Addresses
Shujun Hu
China Mobile
32 Xuanwumen West Ave, Xicheng District
Beijing, Beijing 100053
China
Email: hushujun@chinamobile.com
Zitao Wang
Huawei
101 Software Avenue, Yuhua District
Nanjing, Jiangsu 210012
China
Email: wangzitao@huawei.com
Fengwei Qin
China Mobile
32 Xuanwumen West Ave, Xicheng District
Beijing, Beijing 100053
China
Email: qinfengwei@chinamobile.com
Hu, et al. Expires January 1, 2019 [Page 19]
Internet-Draft CU separation protocol June 2018
Zhenqiang Li
China Mobile
32 Xuanwumen West Ave, Xicheng District
Beijing, Beijing 100053
China
Email: lizhenqiang@chinamobile.com
Jun Song
Huawei
101 Software Avenue, Yuhua District
Nanjing, Jiangsu 210012
China
Hu, et al. Expires January 1, 2019 [Page 20]