Network Service Header Metadata Type 2 Variable-Length Context Headers
draft-ietf-sfc-nsh-tlv-11
The information below is for an old version of the document.
| Document | Type |
This is an older version of an Internet-Draft that was ultimately published as RFC 9263.
|
|
|---|---|---|---|
| Authors | Yuehua Wei , Uri Elzur , Sumandra Majee , Carlos Pignataro , Donald E. Eastlake 3rd | ||
| Last updated | 2022-01-12 | ||
| RFC stream | Internet Engineering Task Force (IETF) | ||
| Formats | |||
| Reviews | |||
| Additional resources | Mailing list discussion | ||
| Stream | WG state | Submitted to IESG for Publication | |
| Document shepherd | Greg Mirsky | ||
| Shepherd write-up | Show Last changed 2021-09-01 | ||
| IESG | IESG state | Became RFC 9263 (Proposed Standard) | |
| Consensus boilerplate | Yes | ||
| Telechat date |
(None)
Needs 2 more YES or NO OBJECTION positions to pass. |
||
| Responsible AD | Martin Vigoureux | ||
| Send notices to | gregimirsky@gmail.com | ||
| IANA | IANA review state | Version Changed - Review Needed |
draft-ietf-sfc-nsh-tlv-11
SFC Yuehua. Wei, Ed.
Internet-Draft ZTE Corporation
Intended status: Standards Track U. Elzur
Expires: 16 July 2022 Intel
S. Majee
Individual contributor
C. Pignataro
Cisco
D. Eastlake
Futurewei Technologies
12 January 2022
Network Service Header Metadata Type 2 Variable-Length Context Headers
draft-ietf-sfc-nsh-tlv-11
Abstract
Service Function Chaining (SFC) uses the Network Service Header (NSH)
(RFC 8300) to steer and provide context Metadata (MD) with each
packet. Such Metadata can be of various Types including MD Type 2
variable length context headers. This document specifies several
such context headers that can be used within a service function path.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
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."
This Internet-Draft will expire on 16 July 2022.
Copyright Notice
Copyright (c) 2022 IETF Trust and the persons identified as the
document authors. All rights reserved.
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This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents (https://trustee.ietf.org/
license-info) in effect on the date of publication of this document.
Please review these documents carefully, as they describe your rights
and restrictions with respect to this document. Code Components
extracted from this document must include Revised BSD License text as
described in Section 4.e of the Trust Legal Provisions and are
provided without warranty as described in the Revised BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Conventions used in this document . . . . . . . . . . . . . . 3
2.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3
2.2. Requirements Language . . . . . . . . . . . . . . . . . . 3
3. NSH MD Type 2 format . . . . . . . . . . . . . . . . . . . . 3
4. NSH MD Type 2 Context Headers . . . . . . . . . . . . . . . . 4
4.1. Forwarding Context . . . . . . . . . . . . . . . . . . . 4
4.2. Tenant Identifier . . . . . . . . . . . . . . . . . . . . 6
4.3. Ingress Network Node Information . . . . . . . . . . . . 6
4.4. Ingress Network Source Interface . . . . . . . . . . . . 7
4.5. Flow ID . . . . . . . . . . . . . . . . . . . . . . . . . 8
4.6. Source and/or Destination Groups . . . . . . . . . . . . 8
4.7. Policy Identifier . . . . . . . . . . . . . . . . . . . . 9
5. Security Considerations . . . . . . . . . . . . . . . . . . . 9
6. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 10
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10
7.1. MD Type 2 Context Types . . . . . . . . . . . . . . . . . 10
7.2. Forwarding Context Types . . . . . . . . . . . . . . . . 10
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 11
8.1. Normative References . . . . . . . . . . . . . . . . . . 11
8.2. Informative References . . . . . . . . . . . . . . . . . 12
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 13
1. Introduction
The Network Service Header (NSH) [RFC8300] is the Service Function
Chaining (SFC) encapsulation that supports the SFC architecture
[RFC7665]. As such, the NSH provides following key elements:
1. Service Function Path (SFP) identification.
2. Indication of location within a Service Function Path.
3. Optional, per-packet metadata (fixed-length or variable-length).
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[RFC8300] further defines two metadata formats (MD Types): 1 and 2.
MD Type 1 defines the fixed-length, 16-octet long metadata, whereas
MD Type 2 defines a variable-length context format for metadata.
This document defines several common metadata context headers for use
with NSH MD Type 2. These supplement the Subscriber Identity and
Performance Policy MD Type 2 metadata context headers specified in
[RFC8979].
This document does not address metadata usage, updating/chaining of
metadata, or other SFP functions. Those topics are described in
[RFC8300].
2. Conventions used in this document
2.1. Terminology
This document uses the terminology defined in the SFC Architecture
[RFC7665] and the Network Service Header [RFC8300].
2.2. Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
3. NSH MD Type 2 format
An NSH is composed of a 4-octet Base Header, a 4-octet Service Path
Header and optional Context Headers. The Base Header identifies the
MD-Type in use:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Ver|O|U| TTL | Length |U|U|U|U|MD Type| Next Protocol |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 1: NSH Base Header
Please refer to NSH [RFC8300] for a detailed header description.
When the base header specifies MD Type = 0x2, zero or more Variable
Length Context Headers MAY be added, immediately following the
Service Path Header. Figure 2 below depicts the format of the
Context Header as defined in Section 2.5.1 of [RFC8300].
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Metadata Class | Type |U| Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Variable-Length Metadata |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2: NSH Variable-Length Context Headers
4. NSH MD Type 2 Context Headers
[RFC8300] specifies Metadata Class 0x0000 as IETF Base NSH MD Class.
In this document, metadata types are defined for the IETF Base NSH MD
Class.
4.1. Forwarding Context
This metadata context carries a network forwarding context, used for
segregation and forwarding scope. Forwarding context can take
several forms depending on the network environment. For example,
VXLAN/VXLAN-GPE VNID, VRF identification, or VLAN.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Metadata Class = 0x0000 | Type = TBA1 |U| Length = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|CT=0x0 | Reserved | VLAN ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 3: Forwarding Context - 1(VLAN)
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Metadata Class = 0x0000 | Type = TBA1 |U| Length = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|CT=0x1 |Resv | Service VLAN ID | Customer VLAN ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 4: Forwarding Context - 2(QinQ)
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Metadata Class = 0x0000 | Type = TBA1 |U| Length = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|CT=0x2 | Reserved | MPLS VPN Label |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 5: Forwarding Context - 3(MPLS VPN)
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Metadata Class = 0x0000 | Type = TBA1 |U| Length = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|CT=0x3 | Resv | Virtual Network Identifier |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 6: Forwarding Context - 4(VNI)
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Metadata Class = 0x0000 | Type = TBA1 |U| Length = 8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|CT=0x4 | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Session ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 7: Forwarding Context - 5(Session ID)
where:
Context Type (CT) is four bits-long field that defines the length
and the interpretation of the Forwarding Context field. Please
see the IANA Considerations in Section 7. This document defines
these CT values:
- 0x0 - 12 bits VLAN identifier. See Figure 3. Reserved bits
MUST be sent as zero and ignored on receipt
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- 0x1 - 24 bits double tagging identifiers. A service VLAN tag
followed by a customer VLAN tag [IEEE.802.1Q_2018]. The two
VLAN IDs are concatenated and appear in the same order that
they appeared in the payload. See Figure 4. Reserved bits
MUST be sent as zero and ignored on receipt
- 0x2 - 20 bits MPLS VPN label. See Figure 5. Reserved bits
MUST be sent as zero and ignored on receipt
- 0x3 - 24 bits virtual network identifier (VNI). See Figure 6.
Reserved bits MUST be sent as zero and ignored on receipt
- 0x4 - 32 bits Session ID ([RFC3931]). This is called Key in
GRE [RFC2890]. See Figure 7.
4.2. Tenant Identifier
Tenant identification is often used for segregation within a multi-
tenant environment. Orchestration system-generated tenant IDs are an
example of such data. This context header carries the value of the
Tenant identifier.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Metadata Class = 0x0000 | Type = TBA2 |U| Length = var|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ Tenant ID ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 8: Tenant Identifier List
The fields are described as follows:
Length: Indicates the length of the Tenant ID in octets (see
Section 2.5.1 of [RFC8300]).
Tenant ID: Represents an opaque value pointing to Orchestration
system-generated tenant identifier. The structure and semantics
of this field are deployment specific.
4.3. Ingress Network Node Information
This context header carries a Node ID of the ingress network node.
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Metadata Class = 0x0000 | Type = TBA3 |U| Length = var|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ Node ID ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 9: Ingress Network Node ID
The fields are described as follows:
Length: Indicates the length of the Node ID in octets (see
Section 2.5.1 of [RFC8300]).
Node ID: Represents an opaque value of the ingress network node
ID. The structure and semantics of this field are deployment
specific. For example, Node ID may be a 4 octets IPv4 address
Node ID, or a 16 octets IPv6 address Node ID, or a 6 octets MAC
address, or 8 octets MAC address (EUI-64), etc.
4.4. Ingress Network Source Interface
This context identifies the ingress interface of the ingress network
node.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Metadata Class = 0x0000 | Type = TBA4 |U| Length = var|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ Source Interface ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 10: Ingress Network Source Interface
The fields are described as follows:
Length: Indicates the length of the Source Interface in octets
(see Section 2.5.1 of [RFC8300]).
Source Interface: Represents an opaque value of identifier of the
ingress interface of the ingress network node.
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4.5. Flow ID
Flow ID provides a field in the NSH MD Type 2 to label packets
belonging to the same flow. Absence of this field, or a value of
zero denotes that packets have not been labeled.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Metadata Class = 0x0000 | Type = TBA5 |U| Length = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Flow ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 11: Flow ID
The fields are described as follows:
Length: Indicates the length of the Flow ID in octets (see
Section 2.5.1 of [RFC8300]). [RFC8200] defined IPv6 Flow Label as
a 20-bit long unsigned integer. Also, [RFC6790], which defined
the use of an entropy label in the MPLS network, is 20-bit long.
Flow ID: Represents an opaque value of the Flow ID. The Flow ID
is right justified (appears in the least significant bits of the
Flow ID word) and is padded on the left with bits which MUST be
sent as zero and ignored on receipt.
4.6. Source and/or Destination Groups
Intent-based systems can use this data to express the logical
grouping of source and/or destination objects. [OpenStack] and
[OpenDaylight] provide examples of such a system. Each is expressed
as a 32-bit opaque object.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Metadata Class = 0x0000 | Type = TBA6 |U| Length=8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Source Group |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Dest Group |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 12: Source/Dest Groups
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4.7. Policy Identifier
Traffic handling policies are often referred to by a system-generated
identifier, which is then used by the devices to look up the policy's
content locally. For example, this identifier could be an index to
an array, a lookup key, a database Id. The identifier allows
enforcement agents or services to look up the content of their part
of the policy.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Metadata Class = 0x0000 | Type = TBA7 |U| Length=var |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ Policy ID ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 13: Policy ID
The fields are described as follows:
Length: Indicates the length of the Policy ID in octets (see
Section 2.5.1 of [RFC8300]).
Policy ID: Represents an opaque value of the Policy ID.
This policy identifier is a general policy ID, essentially a key to
allow Service Functions to know which policies to apply to packets.
Those policies generally will not have much to do with performance,
but rather with what specific treatment to apply. It may for example
select a URL filter data set for a URL filter, or select a video
transcoding policy in a transcoding SF. The Performance Policy
Identifier in [RFC8979] is described there as having very specific
use, and for example says that fully controlled SFPs would not use
it. The Policy ID in this document is for cases not covered by
[RFC8979].
5. Security Considerations
A misbehaving node from within the SFC-enabled domain may alter the
content of the Context Headers, which may lead to service disruption.
Such an attack is not unique to the Context Headers defined in this
document. Measures discussed in Section 8 of [RFC8300] describes the
general security considerations for protecting NSH.
[I-D.ietf-sfc-nsh-integrity] specifies methods of protecting the
integrity of the NSH metadata. If the NSH includes the MAC Context
Header, the authentication of the packet MUST be verified before
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using any data. If the verification fails, the receiver MUST stop
processing the variable length context headers and notify an
operator.
6. Acknowledgments
The authors would like to thank Paul Quinn, Behcet Sarikaya, Dirk von
Hugo, Mohamed Boucadair, Gregory Mirsky, and Joel Halpern for
providing invaluable concepts and content for this document.
7. IANA Considerations
7.1. MD Type 2 Context Types
IANA is requested to assign the following types (Table 1) from the
"NSH IETF- Assigned Optional Variable-Length Metadata Types" registry
available at [IANA-NSH-MD2].These Metadata Types only apply when the
Metadata Class is 0x000 (IETF Base NSH MD Class)
+=======+==================================+===============+
| Value | Description | Reference |
+=======+==================================+===============+
| TBA1 | Forwarding Context | This document |
+-------+----------------------------------+---------------+
| TBA2 | Tenant Identifier | This document |
+-------+----------------------------------+---------------+
| TBA3 | Ingress Network NodeID | This document |
+-------+----------------------------------+---------------+
| TBA4 | Ingress Network Interface | This document |
+-------+----------------------------------+---------------+
| TBA5 | Flow ID | This document |
+-------+----------------------------------+---------------+
| TBA6 | Source and/or Destination Groups | This document |
+-------+----------------------------------+---------------+
| TBA7 | Policy Identifier | This document |
+-------+----------------------------------+---------------+
Table 1: Type Values
7.2. Forwarding Context Types
IANA is requested to create a new sub-registry for "Forwarding
Context" context types at [IANA-NSH-MD2] as follows:
The Registration Policy is IETF Review
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+=========+=========================================+===============+
| Value | Forwarding Context Header Types | Reference |
+=========+=========================================+===============+
| 0x0 | 12-bit VLAN identifier | This document |
+---------+-----------------------------------------+---------------+
| 0x1 | 24-bit double tagging identifiers | This document |
+---------+-----------------------------------------+---------------+
| 0x2 | 20-bit MPLS VPN label | This document |
+---------+-----------------------------------------+---------------+
| 0x3 | 24-bit virtual network identifier | This document |
| | (VNI) | |
+---------+-----------------------------------------+---------------+
| 0x4 | 32-bit Session ID | This document |
+---------+-----------------------------------------+---------------+
| 0x5-0xE | Unassigned | |
+---------+-----------------------------------------+---------------+
| 0xF | Reserved | This document |
+---------+-----------------------------------------+---------------+
Table 2: Forwarding Context Types
8. References
8.1. Normative References
[I-D.ietf-sfc-nsh-integrity]
Boucadair, M., Reddy, T., and D. Wing, "Integrity
Protection for the Network Service Header (NSH) and
Encryption of Sensitive Context Headers", Work in
Progress, Internet-Draft, draft-ietf-sfc-nsh-integrity-09,
20 September 2021, <https://www.ietf.org/archive/id/draft-
ietf-sfc-nsh-integrity-09.txt>.
[IANA-NSH-MD2]
IANA, "NSH IETF-Assigned Optional Variable-Length Metadata
Types", <https://www.iana.org/assignments/nsh/
nsh.xhtml#optional-variable-length-metadata-types>.
[IEEE.802.1Q_2018]
IEEE, "IEEE Standard for Local and Metropolitan Area
Networks--Bridges and Bridged Networks", July 2018,
<http://ieeexplore.ieee.org/servlet/
opac?punumber=8403925>.
[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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[RFC3931] Lau, J., Ed., Townsley, M., Ed., and I. Goyret, Ed.,
"Layer Two Tunneling Protocol - Version 3 (L2TPv3)",
RFC 3931, DOI 10.17487/RFC3931, March 2005,
<https://www.rfc-editor.org/info/rfc3931>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[RFC8300] Quinn, P., Ed., Elzur, U., Ed., and C. Pignataro, Ed.,
"Network Service Header (NSH)", RFC 8300,
DOI 10.17487/RFC8300, January 2018,
<https://www.rfc-editor.org/info/rfc8300>.
8.2. Informative References
[OpenDaylight]
OpenDaylight, "Group Based Policy", 2021,
<https://docs.opendaylight.org/en/stable-fluorine/user-
guide/group-based-policy-user-
guide.html?highlight=group%20policy#>.
[OpenStack]
OpenStack, "Group Based Policy", 2021,
<https://wiki.openstack.org/wiki/GroupBasedPolicy>.
[RFC2890] Dommety, G., "Key and Sequence Number Extensions to GRE",
RFC 2890, DOI 10.17487/RFC2890, September 2000,
<https://www.rfc-editor.org/info/rfc2890>.
[RFC6790] Kompella, K., Drake, J., Amante, S., Henderickx, W., and
L. Yong, "The Use of Entropy Labels in MPLS Forwarding",
RFC 6790, DOI 10.17487/RFC6790, November 2012,
<https://www.rfc-editor.org/info/rfc6790>.
[RFC7665] Halpern, J., Ed. and C. Pignataro, Ed., "Service Function
Chaining (SFC) Architecture", RFC 7665,
DOI 10.17487/RFC7665, October 2015,
<https://www.rfc-editor.org/info/rfc7665>.
[RFC8200] Deering, S. and R. Hinden, "Internet Protocol, Version 6
(IPv6) Specification", STD 86, RFC 8200,
DOI 10.17487/RFC8200, July 2017,
<https://www.rfc-editor.org/info/rfc8200>.
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[RFC8979] Sarikaya, B., von Hugo, D., and M. Boucadair, "Subscriber
and Performance Policy Identifier Context Headers in the
Network Service Header (NSH)", RFC 8979,
DOI 10.17487/RFC8979, February 2021,
<https://www.rfc-editor.org/info/rfc8979>.
Authors' Addresses
Yuehua Wei (editor)
ZTE Corporation
No.50, Software Avenue
Nanjing
210012
China
Email: wei.yuehua@zte.com.cn
Uri Elzur
Intel
Email: uri.elzur@intel.com
Sumandra Majee
Individual contributor
Email: Sum.majee@gmail.com
Carlos Pignataro
Cisco
Email: cpignata@cisco.com
Donald E. Eastlake
Futurewei Technologies
Email: d3e3e3@gmail.com
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