rfc9263.original   rfc9263.txt 
Service Function Chaining Working Group Yuehua. Wei, Ed. Internet Engineering Task Force (IETF) Y. Wei, Ed.
Internet-Draft ZTE Corporation Request for Comments: 9263 ZTE Corporation
Intended status: Standards Track U. Elzur Category: Standards Track U. Elzur
Expires: 22 October 2022 Intel ISSN: 2070-1721 Intel
S. Majee S. Majee
Individual contributor Individual Contributor
C. Pignataro C. Pignataro
Cisco Cisco
D. Eastlake D. Eastlake 3rd
Futurewei Technologies Futurewei Technologies
20 April 2022 August 2022
Network Service Header (NSH) Metadata Type 2 Variable-Length Context Network Service Header (NSH) Metadata Type 2 Variable-Length Context
Headers Headers
draft-ietf-sfc-nsh-tlv-15
Abstract Abstract
Service Function Chaining (SFC) uses the Network Service Header (NSH) Service Function Chaining (SFC) uses the Network Service Header (NSH)
(RFC 8300) to steer and provide context Metadata (MD) with each (RFC 8300) to steer and provide context metadata (MD) with each
packet. Such Metadata can be of various Types including MD Type 2 packet. Such metadata can be of various types, including MD Type 2,
consisting of variable length context headers. This document consisting of Variable-Length Context Headers. This document
specifies several such context headers that can be used within a specifies several such Context Headers that can be used within a
service function path. Service Function Path (SFP).
Status of This Memo Status of This Memo
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Internet Standards is available in Section 2 of RFC 7841.
This Internet-Draft will expire on 22 October 2022. Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
https://www.rfc-editor.org/info/rfc9263.
Copyright Notice Copyright Notice
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction
2. Conventions used in this document . . . . . . . . . . . . . . 3 2. Conventions Used in This Document
2.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3 2.1. Terminology
2.2. Requirements Language . . . . . . . . . . . . . . . . . . 3 2.2. Requirements Language
3. NSH MD Type 2 format . . . . . . . . . . . . . . . . . . . . 3 3. NSH MD Type 2 Format
4. NSH MD Type 2 Context Headers . . . . . . . . . . . . . . . . 4 4. NSH MD Type 2 Context Headers
4.1. Forwarding Context . . . . . . . . . . . . . . . . . . . 4 4.1. Forwarding Context
4.2. Tenant Identifier . . . . . . . . . . . . . . . . . . . . 6 4.2. Tenant ID
4.3. Ingress Network Node Information . . . . . . . . . . . . 7 4.3. Ingress Network Node Information
4.4. Ingress Network Source Interface . . . . . . . . . . . . 8 4.4. Ingress Network Source Interface
4.5. Flow ID . . . . . . . . . . . . . . . . . . . . . . . . . 8 4.5. Flow ID
4.6. Source and/or Destination Groups . . . . . . . . . . . . 9 4.6. Source and/or Destination Groups
4.7. Policy Identifier . . . . . . . . . . . . . . . . . . . . 10 4.7. Policy ID
5. Security Considerations . . . . . . . . . . . . . . . . . . . 11 5. Security Considerations
5.1. Forwarding Context . . . . . . . . . . . . . . . . . . . 11 5.1. Forwarding Context
5.2. Tenant Identifier . . . . . . . . . . . . . . . . . . . . 12 5.2. Tenant ID
5.3. Ingress Network Node Information . . . . . . . . . . . . 12 5.3. Ingress Network Node Information
5.4. Ingress Node Source Interface . . . . . . . . . . . . . . 12 5.4. Ingress Node Source Interface
5.5. Flow ID . . . . . . . . . . . . . . . . . . . . . . . . . 12 5.5. Flow ID
5.6. Source and/or Destination Groups . . . . . . . . . . . . 13 5.6. Source and/or Destination Groups
5.7. Policy Identifier . . . . . . . . . . . . . . . . . . . . 13 5.7. Policy ID
6. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 13 6. IANA Considerations
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13 6.1. MD Type 2 Context Types
7.1. MD Type 2 Context Types . . . . . . . . . . . . . . . . . 13 6.2. Forwarding Context Types
7.2. Forwarding Context Types . . . . . . . . . . . . . . . . 14 6.3. Flow ID Context Types
7.3. Flow ID Context Types . . . . . . . . . . . . . . . . . . 15 7. References
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 15 7.1. Normative References
8.1. Normative References . . . . . . . . . . . . . . . . . . 15 7.2. Informative References
8.2. Informative References . . . . . . . . . . . . . . . . . 16 Acknowledgments
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 17 Authors' Addresses
1. Introduction 1. Introduction
The Network Service Header (NSH) [RFC8300] is the Service Function The Network Service Header (NSH) [RFC8300] is the Service Function
Chaining (SFC) encapsulation that supports the SFC architecture Chaining (SFC) encapsulation that supports the SFC architecture
[RFC7665]. As such, the NSH provides following key elements: [RFC7665]. As such, the NSH provides the following key elements:
1. Service Function Path (SFP) identification. 1. Service Function Path (SFP) identification
2. Indication of location within a Service Function Path. 2. indication of location within an SFP
3. Optional, per-packet metadata (fixed-length or variable-length). 3. optional, per-packet metadata (fixed-length or variable-length)
[RFC8300] further defines two metadata formats (MD Types): 1 and 2. [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 1 defines the fixed-length, 16-octet metadata, whereas MD
MD Type 2 defines a variable-length context format for metadata. Type 2 defines a variable-length context format for metadata. This
This document defines several common metadata context headers for use document defines several common metadata Context Headers for use
within NSH MD Type 2. These supplement the Subscriber Identity and within NSH MD Type 2. These supplement the Subscriber Identifier and
Performance Policy MD Type 2 metadata context headers specified in Performance Policy MD Type 2 metadata Context Headers specified in
[RFC8979]. [RFC8979].
This document does not address metadata usage, updating/chaining of This document does not address metadata usage, updating/chaining of
metadata, or other SFP functions. Those topics are described in metadata, or other SFP functions. Those topics are described in
[RFC8300]. [RFC8300].
2. Conventions used in this document 2. Conventions Used in This Document
2.1. Terminology 2.1. Terminology
This document uses the terminology defined in the SFC Architecture This document uses the terminology defined in the SFC architecture
[RFC7665] and the Network Service Header [RFC8300]. [RFC7665] and the NSH [RFC8300].
2.2. Requirements Language 2.2. Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP "OPTIONAL" in this document are to be interpreted as described in
14 [RFC2119] [RFC8174] when, and only when, they appear in all BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here. capitals, as shown here.
3. NSH MD Type 2 format 3. NSH MD Type 2 Format
An NSH is composed of a 4-octet Base Header, a 4-octet Service Path 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 Header, and optional Context Headers. The Base Header identifies the
MD-Type in use: MD Type in use:
0 1 2 3 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 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 | |Ver|O|U| TTL | Length |U|U|U|U|MD Type| Next Protocol |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 1: NSH Base Header Figure 1: NSH Base Header
Please refer to NSH [RFC8300] for a detailed header description. Please refer to the NSH [RFC8300] for a detailed header description.
When the base header specifies MD Type = 0x2, zero or more Variable When the Base Header specifies MD Type = 0x2, zero or more Variable-
Length Context Headers MAY be added, immediately following the Length Context Headers MAY be added, immediately following the
Service Path Header. Figure 2 below depicts the format of the Service Path Header. Figure 2 below depicts the format of the
Context Header as defined in Section 2.5.1 of [RFC8300]. Context Header as defined in Section 2.5.1 of [RFC8300].
0 1 2 3 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 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 | | Metadata Class | Type |U| Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Variable-Length Metadata | | Variable-Length Metadata |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2: NSH Variable-Length Context Headers Figure 2: NSH Variable-Length Context Headers
4. NSH MD Type 2 Context Headers 4. NSH MD Type 2 Context Headers
[RFC8300] specifies Metadata Class 0x0000 as IETF Base NSH MD Class. [RFC8300] specifies Metadata Class 0x0000 as IETF Base NSH MD Class.
In this document, metadata types are defined for the IETF Base NSH MD In this document, metadata types are defined for the IETF Base NSH MD
Class. The Context Headers specified in the subsections below are as Class. The Context Headers specified in the subsections below are as
follows: follows:
1. Forwarding Context 1. Forwarding Context
2. Tenant Identifier 2. Tenant ID
3. Ingress Network Node Information 3. Ingress Network Node Information
4. Ingress Node Source Interface 4. Ingress Node Source Interface
5. Flow ID 5. Flow ID
6. Source and/or Destination Groups 6. Source and/or Destination Groups
7. Policy Identifier 7. Policy ID
4.1. Forwarding Context 4.1. Forwarding Context
This metadata context carries a network forwarding context, used for This metadata context carries a network forwarding context, used for
segregation and forwarding scope. Forwarding context can take segregation and forwarding scope. Forwarding context can take
several forms depending on the network environment. For example, several forms depending on the network environment, for example,
VXLAN/VXLAN-GPE VNID, VRF identification, or VLAN. Virtual eXtensible Local Area Network (VXLAN) / Generic Protocol
Extension for VXLAN (VXLAN-GPE) Virtual Network Identifier (VNID),
VPN Routing and Forwarding (VRF) identification, or VLAN.
0 1 2 3 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 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 | | Metadata Class = 0x0000 | Type = 0x04 |U| Length = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|CT=0x0 | Reserved | VLAN ID | |CT=0x0 | Reserved | VLAN ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 3: VLAN Forwarding Context Figure 3: VLAN Forwarding Context
0 1 2 3 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 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 | | Metadata Class = 0x0000 | Type = 0x04 |U| Length = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|CT=0x1 |Resv | Service VLAN ID | Customer VLAN ID | |CT=0x1 |Resv | Service VLAN ID | Customer VLAN ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 4: QinQ Forwarding Context Figure 4: QinQ Forwarding Context
0 1 2 3 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 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 | | Metadata Class = 0x0000 | Type = 0x04 |U| Length = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|CT=0x2 | Reserved | MPLS VPN Label | |CT=0x2 | Reserved | MPLS VPN Label |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 5: MPLS VPN Forwarding Context Figure 5: MPLS VPN Forwarding Context
0 1 2 3 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 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 | | Metadata Class = 0x0000 | Type = 0x04 |U| Length = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|CT=0x3 | Resv | Virtual Network Identifier | |CT=0x3 | Resv | Virtual Network Identifier |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 6: VNI Forwarding Context Figure 6: VNI Forwarding Context
0 1 2 3 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 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 | | Metadata Class = 0x0000 | Type = 0x04 |U| Length = 8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|CT=0x4 | Reserved | |CT=0x4 | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Session ID | | Session ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 7: Session ID Forwarding Context Figure 7: Session ID Forwarding Context
where: The fields are described as follows:
Context Type (CT) is four bits-long field that defines the Context Type (CT): This 4-bit field that defines the interpretation
interpretation of the Forwarding Context field. Please see the of the Forwarding Context field. Please see the IANA
IANA Considerations in Section 7.2. This document defines these considerations in Section 6.2. This document defines these CT
CT values: values:
- 0x0 - 12 bits VLAN identifier [IEEE.802.1Q_2018]. See 0x0: 12-bit VLAN identifier [IEEE.802.1Q_2018]. See Figure 3.
Figure 3.
- 0x1 - 24 bits double tagging identifiers. A service VLAN tag 0x1: 24-bit double tagging identifiers. A service VLAN tag
followed by a customer VLAN tag [IEEE.802.1Q_2018]. The two followed by a customer VLAN tag [IEEE.802.1Q_2018]. The two
VLAN IDs are concatenated and appear in the same order that VLAN IDs are concatenated and appear in the same order that
they appeared in the payload. See Figure 4. they appeared in the payload. See Figure 4.
- 0x2 - 20 bits MPLS VPN label([RFC3032])([RFC4364]). See 0x2: 20-bit MPLS VPN label [RFC3032] [RFC4364]. See Figure 5.
Figure 5.
- 0x3 - 24 bits virtual network identifier (VNI)[RFC8926]. See 0x3: 24-bit virtual network identifier (VNI) [RFC8926]. See
Figure 6. Figure 6.
- 0x4 - 32 bits Session ID ([RFC3931]). This is called Key in 0x4: 32-bit Session ID [RFC3931]. This is called Key in GRE
GRE [RFC2890]. See Figure 7. [RFC2890]. See Figure 7.
Reserved (Resv) bits in the context fields MUST be sent as zero Reserved (Resv): These bits in the context fields MUST be sent as
and ignored on receipt. zero and ignored on receipt.
4.2. Tenant Identifier 4.2. Tenant ID
Tenant identification is often used for segregation within a multi- Tenant identification is often used for segregation within a multi-
tenant environment. Orchestration system-generated tenant IDs are an tenant environment. Orchestration system-generated Tenant IDs are an
example of such data. This context header carries the value of the example of such data. This Context Header carries the value of the
Tenant identifier. [OpenDaylight-VTN] Virtual Tenant Network (VTN) Tenant ID. Virtual Tenant Network (VTN) [OpenDaylight-VTN] is an
is an application that provides multi-tenant virtual network on an application that provides multi-tenant virtual networks on a
SDN controller. Software-Defined Networking (SDN) controller.
0 1 2 3 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 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 | | Metadata Class = 0x0000 | Type = 0x05 |U| Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ Tenant ID ~ ~ Tenant ID ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 8: Tenant Identifier List Figure 8: Tenant ID List
The fields are described as follows: The fields are described as follows:
Length: Indicates the length of the Tenant ID in octets (see Length: Indicates the length of the Tenant ID in octets (see
Section 2.5.1 of [RFC8300]). Section 2.5.1 of [RFC8300]).
Tenant ID: Represents an opaque value pointing to Orchestration Tenant ID: Represents an opaque value pointing to orchestration
system-generated tenant identifier. The structure and semantics system-generated Tenant ID. The structure and semantics of this
of this field are specific to the operator's deployment across its field are specific to the operator's deployment across its
operational domain, and are specified and assigned by an operational domain and are specified and assigned by an
orchestration function. The specifics of that orchestration-based orchestration function. The specifics of that orchestration-based
assignment are outside the scope of this document. assignment are outside the scope of this document.
4.3. Ingress Network Node Information 4.3. Ingress Network Node Information
This context header carries a Node ID of the network node at which This Context Header carries a Node ID of the network node at which
the packet entered the SFC-enabled domain. This node will the packet entered the SFC-enabled domain. This node will
necessarily be a Classifier [RFC7665]. In cases where the SPI necessarily be a classifier [RFC7665]. In cases where the Service
identifies the ingress node, this context header is superfluous. Path Identifier (SPI) identifies the ingress node, this Context
Header is superfluous.
0 1 2 3 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 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 | | Metadata Class = 0x0000 | Type = 0x06 |U| Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ Node ID ~ ~ Node ID ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 9: Ingress Network Node ID Figure 9: Ingress Network Node ID
The fields are described as follows: The fields are described as follows:
Length: Indicates the length of the Node ID in octets (see Length: Indicates the length of the Node ID in octets (see
Section 2.5.1 of [RFC8300]). Section 2.5.1 of [RFC8300]).
Node ID: Represents an opaque value of the ingress network node Node ID: Represents an opaque value of the ingress network Node ID.
ID. The structure and semantics of this field are deployment The structure and semantics of this field are deployment specific.
specific. For example, Node ID may be a 4 octets IPv4 address For example, Node ID may be a 4-octet IPv4 address Node ID, a
Node ID, or a 16 octets IPv6 address Node ID, or a 6 octets MAC 16-octet IPv6 address Node ID, a 6-octet MAC address, an 8-octet
address, or 8 octets MAC address (EUI-64), etc. MAC address (64-bit Extended Unique Identifier (EUI-64)), etc.
4.4. Ingress Network Source Interface 4.4. Ingress Network Source Interface
This context identifies the ingress interface of the ingress network This context identifies the ingress interface of the ingress network
node. The l2vlan (135), l3ipvlan (136), ipForward (142), mpls (166) node. The l2vlan (135), l3ipvlan (136), ipForward (142), and mpls
in [IANAifType] are examples of source interfaces. (166) in [IANAifType] are examples of source interfaces.
0 1 2 3 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 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 | | Metadata Class = 0x0000 | Type = 0x07 |U| Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ Source Interface ~ ~ Source Interface ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 10: Ingress Network Source Interface Figure 10: Ingress Network Source Interface
The fields are described as follows: The fields are described as follows:
Length: Indicates the length of the Source Interface in octets Length: Indicates the length of the Source Interface in octets (see
(see Section 2.5.1 of [RFC8300]). Section 2.5.1 of [RFC8300]).
Source Interface: Represents an opaque value of identifier of the Source Interface: Represents an opaque value of the identifier of
ingress interface of the ingress network node. the ingress interface of the ingress network node.
4.5. Flow ID 4.5. Flow ID
Flow ID provides a field in the NSH MD Type 2 to label packets Flow ID provides a field in NSH MD Type 2 to label packets belonging
belonging to the same flow. For example, [RFC8200] defined IPv6 Flow to the same flow. For example, [RFC8200] defines IPv6 Flow Label as
Label as Flow ID, [RFC6790] defined an entropy label which is Flow ID. Another example of Flow ID is how [RFC6790] defines an
generated based on flow information in the MPLS network is another entropy label that is generated based on flow information in the MPLS
example of Flow ID. Absence of this field, or a value of zero network. Absence of this field or a value of zero denotes that
denotes that packets have not been labeled with a Flow ID. packets have not been labeled with a Flow ID.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Metadata Class = 0x0000 | Type = 0x08 |U| Length = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|CT=0x0 | Reserved | IPv6 Flow ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Metadata Class = 0x0000 | Type = TBA5 |U| Length = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|CT=0x0 | Reserved | IPv6 Flow ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 11: IPv6 Flow ID Figure 11: IPv6 Flow ID
0 1 2 3 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 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 | | Metadata Class = 0x0000 | Type = 0x08 |U| Length = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|CT=0x1 | Reserved | MPLS entropy label | |CT=0x1 | Reserved | MPLS entropy label |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 12: MPLS entropy label Figure 12: MPLS Entropy Label
The fields are described as follows: The fields are described as follows:
Length: Indicates the length of the Flow ID in octets (see Length: Indicates the length of the Flow ID in octets (see
Section 2.5.1 of [RFC8300]). For example, IPv6 Flow Label in Section 2.5.1 of [RFC8300]). For example, the IPv6 Flow Label in
[RFC8200] is 20-bit long. An entropy label in the MPLS network in [RFC8200] is 20 bits long. An entropy label in the MPLS network
[RFC6790] is also 20-bit long. in [RFC6790] is also 20 bits long.
Context Type (CT) is four bits-long field that defines the Context Type (CT): This 4-bit field that defines the interpretation
interpretation of the Flow ID field. Please see the IANA of the Flow ID field. Please see the IANA considerations in
Considerations in Section 7.3. This document defines these CT Section 6.3. This document defines these CT values:
values:
- 0x0 - 20 bits IPv6 Flow Label in [RFC8200]. See Figure 11. 0x0: 20-bit IPv6 Flow Label in [RFC8200]. See Figure 11.
- 0x1 - 20 bits entropy label in the MPLS network in [RFC6790]. 0x1: 20-bit entropy label in the MPLS network in [RFC6790]. See
See Figure 12. Figure 12.
Reserved bits in the context fields MUST be sent as zero and Reserved: These bits in the context fields MUST be sent as zero and
ignored on receipt. ignored on receipt.
4.6. Source and/or Destination Groups 4.6. Source and/or Destination Groups
Intent-based systems can use this data to express the logical Intent-based systems can use this data to express the logical
grouping of source and/or destination objects. [OpenStack] and grouping of source and/or destination objects. [OpenStack] and
[OpenDaylight] provide examples of such a system. Each is expressed [OpenDaylight] provide examples of such a system. Each is expressed
as a 32-bit opaque object. as a 32-bit opaque object.
0 1 2 3 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 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 | | Metadata Class = 0x0000 | Type = 0x09 |U| Length=8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Source Group | | Source Group |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Destination Group | | Destination Group |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 13: Source/Destination Groups Figure 13: Source/Destination Groups
If there is no group information specified for the source group or If there is no group information specified for the Source Group or
destination group field, the field MUST be sent as zero and ignored Destination Group field, the field MUST be sent as zero and ignored
on receipt. on receipt.
4.7. Policy Identifier 4.7. Policy ID
Traffic handling policies are often referred to by a system-generated 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 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 content locally. For example, this identifier could be an index to
an array, a lookup key, a database Id. The identifier allows an array, a lookup key, or a database ID. The identifier allows
enforcement agents or services to look up the content of their part enforcement agents or services to look up the content of their part
of the policy. of the policy.
0 1 2 3 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 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 | | Metadata Class = 0x0000 | Type = 0x0A |U| Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ Policy ID ~ ~ Policy ID ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 14: Policy ID Figure 14: Policy ID
The fields are described as follows: The fields are described as follows:
Length: Indicates the length of the Policy ID in octets (see Length: Indicates the length of the Policy ID in octets (see
Section 2.5.1 of [RFC8300]). Section 2.5.1 of [RFC8300]).
Policy ID: Represents an opaque value of the Policy ID. Policy ID: Represents an opaque value of the Policy ID.
This policy identifier is a general policy ID, essentially a key to This Policy ID is a general Policy ID, essentially a key to allow
allow Service Functions to know which policies to apply to packets. Service Functions (SFs) to know which policies to apply to packets.
Those policies generally will not have much to do with performance, Those policies generally will not have much to do with performance
but rather with what specific treatment to apply. It may for example but rather with what specific treatment to apply. It may, for
select a URL filter data set for a URL filter, or select a video example, select a URL filter data set for a URL filter or select a
transcoding policy in a transcoding SF. The Performance Policy video transcoding policy in a transcoding SF. The Performance Policy
Identifier in [RFC8979] is described there as having very specific ID in [RFC8979] is described there as having very specific use and,
use, and for example says that fully controlled SFPs would not use for example, says that fully controlled SFPs would not use it. The
it. The Policy ID in this document is for cases not covered by Policy ID in this document is for cases not covered by [RFC8979].
[RFC8979].
5. Security Considerations 5. Security Considerations
A misbehaving node from within the SFC-enabled domain may alter the A misbehaving node from within the SFC-enabled domain may alter the
content of the Context Headers, which may lead to service disruption. content of the Context Headers, which may lead to service disruption.
Such an attack is not unique to the Context Headers defined in this Such an attack is not unique to the Context Headers defined in this
document. Measures discussed in Section 8 of [RFC8300] describes the document. Measures discussed in Section 8 of [RFC8300] describes the
general security considerations for protecting NSH. general security considerations for protecting the NSH. [RFC9145]
[I-D.ietf-sfc-nsh-integrity] specifies methods of protecting the specifies methods of protecting the integrity of the NSH metadata.
integrity of the NSH metadata. If the NSH includes the MAC and If the NSH includes the Message Authentication Code (MAC) and
Encrypted Metadata Context Header [RFC9145], the authentication of Encrypted Metadata Context Header [RFC9145], the authentication of
the packet MUST be verified before using any data. If the the packet MUST be verified before using any data. If the
verification fails, the receiver MUST stop processing the variable verification fails, the receiver MUST stop processing the Variable-
length context headers and notify an operator. Length Context Headers and notify an operator.
The security and privacy considerations for the 7 types of context The security and privacy considerations for the 7 types of Context
header specified above are discussed below. Since NSH ignorant SFs Headers specified above are discussed below. Since NSH-ignorant SFs
will never see the NSH, then even if they are malign, they cannot will never see the NSH, then even if they are malign, they cannot
compromise security or privacy based on the NSH or any of these compromise security or privacy based on the NSH or any of these
context headers, although they could cause compromise based on the Context Headers; however, they could cause compromise based on the
rest of the packet. To the extent that any of these headers is rest of the packet. To the extent that any of these headers are
included when it would be unneeded or have no effect, they provide a included when they would be unneeded or have no effect, they provide
covert channel for the entity adding the context header to a covert channel for the entity adding the Context Header to
communicate a limited amount of arbitrary information to downstream communicate a limited amount of arbitrary information to downstream
entities within the SFC-enabled domain. entities within the SFC-enabled domain.
5.1. Forwarding Context 5.1. Forwarding Context
All of the Forwarding Context variants specified in this document All of the Forwarding Context variants specified in this document
(those with CT values between 0 and 4) merely repeat a field that is (those with CT values between 0 and 4) merely repeat a field that is
available in the packet encapsulated by the NSH. These variants available in the packet encapsulated by the NSH. These variants
repeat that field in the NSH for convenience. Thus, there are no repeat that field in the NSH for convenience. Thus, there are no
special security or privacy considerations in these cases. Any special security or privacy considerations in these cases. Any
future new values of CT for the Forwarding Context must specify the future new values of CT for the Forwarding Context must specify the
security and privacy considerations for those extensions. security and privacy considerations for those extensions.
5.2. Tenant Identifier 5.2. Tenant ID
The Tenant ID indicates the tenant to which traffic belongs and might The Tenant ID indicates the tenant to which traffic belongs and might
be used to tie together and correlate packets for a tenant that some be used to tie together and correlate packets for a tenant that some
monitoring function could not otherwise group especially if other monitoring function could not otherwise group, especially if other
possible identifiers were being randomized. As such, it may reduce possible identifiers were being randomized. As such, it may reduce
security by facilitating traffic analysis but only within the SFC- security by facilitating traffic analysis but only within the SFC-
enabled domain where this context header is present in packets. enabled domain where this Context Header is present in packets.
5.3. Ingress Network Node Information 5.3. Ingress Network Node Information
The SFC-enabled domain manager normally operates the initial ingress The SFC-enabled domain manager normally operates the initial ingress/
/ classifier node and is thus potentially aware of the information classifier node and is thus potentially aware of the information
provided by this context header. Furthermore, in many cases the SPI provided by this Context Header. Furthermore, in many cases, the SPI
that will be present in the NSH identifies or closely constrains the that will be present in the NSH identifies or closely constrains the
ingress node. Also, in most cases, it is anticipated that many ingress node. Also, in most cases, it is anticipated that many
entities will be sending packets into an SFC-enabled domain through entities will be sending packets into an SFC-enabled domain through
the same ingress node. Thus, under most circumstances, this context the same ingress node. Thus, under most circumstances, this Context
header is expected to weaken security and privacy to only a minor Header is expected to weaken security and privacy to only a minor
extent and only within the SFC-enabled domain. extent and only within the SFC-enabled domain.
5.4. Ingress Node Source Interface 5.4. Ingress Node Source Interface
This context header is likely to be meaningless unless the Ingress This Context Header is likely to be meaningless unless the Ingress
Network Node Information context header is also present. When that Network Node Information Context Header is also present. When that
node information header is present, this source interface header node information header is present, this source interface header
provides a more fine-grained view of the source by identifying not provides a more fine-grained view of the source by identifying not
just the initial ingress / classifier node but also the port of that just the initial ingress/classifier node but also the port of that
node on which the data arrived. Thus, it is more likely to identify node on which the data arrived. Thus, it is more likely to identify
a specific source entity or at least to more tightly constrain the a specific source entity or at least to more tightly constrain the
set of possible source entities, than just the node information set of possible source entities than just the node information
header. As a result, inclusion of this context header with the node header. As a result, inclusion of this Context Header with the node
information context header is potentially a greater threat to information Context Header is potentially a greater threat to
security and privacy than the node information header alone but this security and privacy than the node information header alone, but this
threat is still constrained to the SFC-enabled domain. threat is still constrained to the SFC-enabled domain.
5.5. Flow ID 5.5. Flow ID
The variations of this context header specified in this document The variations of this Context Header specified in this document
simply repeat fields already available in the packet and thus have no simply repeat fields already available in the packet and thus have no
special security or privacy considerations. Any future new values of special security or privacy considerations. Any future new values of
CT for the Flow ID must specify the security and privacy CT for the Flow ID must specify the security and privacy
considerations for those extensions. considerations for those extensions.
5.6. Source and/or Destination Groups 5.6. Source and/or Destination Groups
This context header provides additional information that might help This Context Header provides additional information that might help
identify the source and/or destination of packets. Depending on the identify the source and/or destination of packets. Depending on the
granularity of the groups, it could either (1) distinguish packets as granularity of the groups, it could either (1) distinguish packets as
part of flows from and/or to objects where those flows could not part of flows from and/or to objects where those flows could not
otherwise be easily distinguished but appear to be part of one or otherwise be easily distinguished but appear to be part of one or
fewer flows or (2) group packet flows that are from and/or to an fewer flows or (2) group packet flows that are from and/or to an
object where those flows could not otherwise be easily grouped for object where those flows could not otherwise be easily grouped for
analysis or whatever. Thus, the presence of this context header with analysis or another purpose. Thus, the presence of this Context
non-zero source and/or destination groups can, within the SFC-enabled Header with non-zero source and/or destination groups can, within the
domain, erode security and privacy to an extent that depends on the SFC-enabled domain, erode security and privacy to an extent that
details of the grouping. depends on the details of the grouping.
5.7. Policy Identifier 5.7. Policy ID
This context header carries an identifier that nodes in the SFC- This Context Header carries an identifier that nodes in the SFC-
enabled domain can use to look up policy to potentially influence enabled domain can use to look up policy to potentially influence
their actions with regard to the packet carrying this header. If their actions with regard to the packet carrying this header. If
there are no such action decisions, then the header should not be there are no such decisions regarding their actions, then the header
included. If are such decisions, the information on which they are should not be included. If there are such decisions, the information
to be based needs to be included somewhere in the packet. There is on which they are to be based needs to be included somewhere in the
no reason for inclusion in this context header to have any security packet. There is no reason for inclusion in this Context Header to
or privacy considerations that would not apply to any other plaintext have any security or privacy considerations that would not apply to
way of including such information. It may provide additional any other plaintext way of including such information. It may
information to help identify a flow of data for analysis. provide additional information to help identify a flow of data for
analysis.
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 6. IANA Considerations
7.1. MD Type 2 Context Types 6.1. MD Type 2 Context Types
IANA is requested to assign the following types (Table 1) from the IANA has assigned the following types (Table 1) from the "NSH IETF-
"NSH IETF-Assigned Optional Variable-Length Metadata Types" registry Assigned Optional Variable-Length Metadata Types" registry available
available at [IANA-NSH-MD2]. at [IANA-NSH-MD2].
+=======+==================================+===============+ +=======+==================================+===========+
| Value | Description | Reference | | Value | Description | Reference |
+=======+==================================+===============+ +=======+==================================+===========+
| TBA1 | Forwarding Context | This document | | 0x04 | Forwarding Context | RFC 9263 |
+-------+----------------------------------+---------------+ +-------+----------------------------------+-----------+
| TBA2 | Tenant Identifier | This document | | 0x05 | Tenant ID | RFC 9263 |
+-------+----------------------------------+---------------+ +-------+----------------------------------+-----------+
| TBA3 | Ingress Network NodeID | This document | | 0x06 | Ingress Network Node ID | RFC 9263 |
+-------+----------------------------------+---------------+ +-------+----------------------------------+-----------+
| TBA4 | Ingress Network Interface | This document | | 0x07 | Ingress Network Interface | RFC 9263 |
+-------+----------------------------------+---------------+ +-------+----------------------------------+-----------+
| TBA5 | Flow ID | This document | | 0x08 | Flow ID | RFC 9263 |
+-------+----------------------------------+---------------+ +-------+----------------------------------+-----------+
| TBA6 | Source and/or Destination Groups | This document | | 0x09 | Source and/or Destination Groups | RFC 9263 |
+-------+----------------------------------+---------------+ +-------+----------------------------------+-----------+
| TBA7 | Policy Identifier | This document | | 0x0A | Policy ID | RFC 9263 |
+-------+----------------------------------+---------------+ +-------+----------------------------------+-----------+
Table 1: Type Values Table 1: Type Values
7.2. Forwarding Context Types 6.2. Forwarding Context Types
IANA is requested to create a new sub-registry for "Forwarding IANA has created a new subregistry for "Forwarding Context Types" at
Context" context types at [IANA-NSH-MD2] as follows: [IANA-NSH-MD2] as follows.
The Registration Policy is IETF Review The registration policy is IETF Review.
+=========+=========================================+===============+ +=========+=========================================+===========+
| Value | Forwarding Context Header Types | Reference | | Value | Description | Reference |
+=========+=========================================+===============+ +=========+=========================================+===========+
| 0x0 | 12-bit VLAN identifier | This document | | 0x0 | 12-bit VLAN identifier | RFC 9263 |
+---------+-----------------------------------------+---------------+ +---------+-----------------------------------------+-----------+
| 0x1 | 24-bit double tagging identifiers | This document | | 0x1 | 24-bit double tagging identifiers | RFC 9263 |
+---------+-----------------------------------------+---------------+ +---------+-----------------------------------------+-----------+
| 0x2 | 20-bit MPLS VPN label | This document | | 0x2 | 20-bit MPLS VPN label | RFC 9263 |
+---------+-----------------------------------------+---------------+ +---------+-----------------------------------------+-----------+
| 0x3 | 24-bit virtual network identifier | This document | | 0x3 | 24-bit virtual network identifier (VNI) | RFC 9263 |
| | (VNI) | | +---------+-----------------------------------------+-----------+
+---------+-----------------------------------------+---------------+ | 0x4 | 32-bit Session ID | RFC 9263 |
| 0x4 | 32-bit Session ID | This document | +---------+-----------------------------------------+-----------+
+---------+-----------------------------------------+---------------+ | 0x5-0xE | Unassigned | |
| 0x5-0xE | Unassigned | | +---------+-----------------------------------------+-----------+
+---------+-----------------------------------------+---------------+ | 0xF | Reserved | RFC 9263 |
| 0xF | Reserved | This document | +---------+-----------------------------------------+-----------+
+---------+-----------------------------------------+---------------+
Table 2: Forwarding Context Types Table 2: Forwarding Context Types
7.3. Flow ID Context Types 6.3. Flow ID Context Types
IANA is requested to create a new sub-registry for "Flow ID Context" IANA has created a new subregistry for "Flow ID Context Types" at
context types at [IANA-NSH-MD2] as follows: [IANA-NSH-MD2] as follows.
The Registration Policy is IETF Review The registration policy is IETF Review.
+=========+==============================+===============+ +=========+==========================================+===========+
| Value | Flow ID Context Header Types | Reference | | Value | Description | Reference |
+=========+==============================+===============+ +=========+==========================================+===========+
| 0x0 | 20-bit IPv6 Flow Label | This document | | 0x0 | 20-bit IPv6 Flow Label | RFC 9263 |
+---------+------------------------------+---------------+ +---------+------------------------------------------+-----------+
| 0x1 | 20-bit entropy label in the | This document | | 0x1 | 20-bit entropy label in the MPLS network | RFC 9263 |
| | MPLS network | | +---------+------------------------------------------+-----------+
+---------+------------------------------+---------------+ | 0x2-0xE | Unassigned | |
| 0x2-0xE | Unassigned | | +---------+------------------------------------------+-----------+
+---------+------------------------------+---------------+ | 0xF | Reserved | RFC 9263 |
| 0xF | Reserved | This document | +---------+------------------------------------------+-----------+
+---------+------------------------------+---------------+
Table 3: Flow ID Context Types Table 3: Flow ID Context Types
8. References 7. References
8.1. Normative References
[I-D.ietf-sfc-nsh-integrity] 7.1. Normative References
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-MD2]
IANA, "NSH IETF-Assigned Optional Variable-Length Metadata IANA, "Network Service Header (NSH) Parameters",
Types", <https://www.iana.org/assignments/nsh/ <https://www.iana.org/assignments/nsh>.
nsh.xhtml#optional-variable-length-metadata-types>.
[IEEE.802.1Q_2018] [IEEE.802.1Q_2018]
IEEE, "IEEE Standard for Local and Metropolitan Area IEEE, "IEEE Standard for Local and Metropolitan Area
Networks--Bridges and Bridged Networks", July 2018, Network -- Bridges and Bridged Networks", July 2018,
<http://ieeexplore.ieee.org/servlet/ <https://ieeexplore.ieee.org/document/8403927>.
opac?punumber=8403925>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997, DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>. <https://www.rfc-editor.org/info/rfc2119>.
[RFC3931] Lau, J., Ed., Townsley, M., Ed., and I. Goyret, Ed., [RFC3931] Lau, J., Ed., Townsley, M., Ed., and I. Goyret, Ed.,
"Layer Two Tunneling Protocol - Version 3 (L2TPv3)", "Layer Two Tunneling Protocol - Version 3 (L2TPv3)",
RFC 3931, DOI 10.17487/RFC3931, March 2005, RFC 3931, DOI 10.17487/RFC3931, March 2005,
<https://www.rfc-editor.org/info/rfc3931>. <https://www.rfc-editor.org/info/rfc3931>.
skipping to change at page 16, line 30 skipping to change at line 677
"Network Service Header (NSH)", RFC 8300, "Network Service Header (NSH)", RFC 8300,
DOI 10.17487/RFC8300, January 2018, DOI 10.17487/RFC8300, January 2018,
<https://www.rfc-editor.org/info/rfc8300>. <https://www.rfc-editor.org/info/rfc8300>.
[RFC9145] Boucadair, M., Reddy.K, T., and D. Wing, "Integrity [RFC9145] Boucadair, M., Reddy.K, T., and D. Wing, "Integrity
Protection for the Network Service Header (NSH) and Protection for the Network Service Header (NSH) and
Encryption of Sensitive Context Headers", RFC 9145, Encryption of Sensitive Context Headers", RFC 9145,
DOI 10.17487/RFC9145, December 2021, DOI 10.17487/RFC9145, December 2021,
<https://www.rfc-editor.org/info/rfc9145>. <https://www.rfc-editor.org/info/rfc9145>.
8.2. Informative References 7.2. Informative References
[IANAifType] [IANAifType]
IANA, "IANAifType", 2021, IANA, "IANAifType-MIB DEFINITIONS", 2021,
<https://www.iana.org/assignments/ianaiftype-mib/ <https://www.iana.org/assignments/ianaiftype-mib/
ianaiftype-mib>. ianaiftype-mib>.
[OpenDaylight] [OpenDaylight]
OpenDaylight, "Group Based Policy", 2021, OpenDaylight, "Group Based Policy User Guide", 2021,
<https://docs.opendaylight.org/en/stable-fluorine/user- <https://docs.opendaylight.org/en/stable-fluorine/user-
guide/group-based-policy-user- guide/group-based-policy-user-
guide.html?highlight=group%20policy#>. guide.html?highlight=group%20policy#>.
[OpenDaylight-VTN] [OpenDaylight-VTN]
OpenDaylight, "OpenDaylight VTN", 2021, <https://nexus.ope OpenDaylight, "OpenDaylight VTN", 2021, <https://nexus.ope
ndaylight.org/content/sites/site/org.opendaylight.docs/mas ndaylight.org/content/sites/site/org.opendaylight.docs/mas
ter/userguide/manuals/userguide/bk-user-guide/ ter/userguide/manuals/userguide/bk-user-guide/
content/_vtn.html>. content/_vtn.html>.
[OpenStack] [OpenStack]
OpenStack, "Group Based Policy", 2021, OpenStack, "GroupBasedPolicy", 2021,
<https://wiki.openstack.org/wiki/GroupBasedPolicy>. <https://wiki.openstack.org/wiki/GroupBasedPolicy>.
[RFC2890] Dommety, G., "Key and Sequence Number Extensions to GRE", [RFC2890] Dommety, G., "Key and Sequence Number Extensions to GRE",
RFC 2890, DOI 10.17487/RFC2890, September 2000, RFC 2890, DOI 10.17487/RFC2890, September 2000,
<https://www.rfc-editor.org/info/rfc2890>. <https://www.rfc-editor.org/info/rfc2890>.
[RFC3032] Rosen, E., Tappan, D., Fedorkow, G., Rekhter, Y., [RFC3032] Rosen, E., Tappan, D., Fedorkow, G., Rekhter, Y.,
Farinacci, D., Li, T., and A. Conta, "MPLS Label Stack Farinacci, D., Li, T., and A. Conta, "MPLS Label Stack
Encoding", RFC 3032, DOI 10.17487/RFC3032, January 2001, Encoding", RFC 3032, DOI 10.17487/RFC3032, January 2001,
<https://www.rfc-editor.org/info/rfc3032>. <https://www.rfc-editor.org/info/rfc3032>.
skipping to change at page 17, line 44 skipping to change at line 739
"Geneve: Generic Network Virtualization Encapsulation", "Geneve: Generic Network Virtualization Encapsulation",
RFC 8926, DOI 10.17487/RFC8926, November 2020, RFC 8926, DOI 10.17487/RFC8926, November 2020,
<https://www.rfc-editor.org/info/rfc8926>. <https://www.rfc-editor.org/info/rfc8926>.
[RFC8979] Sarikaya, B., von Hugo, D., and M. Boucadair, "Subscriber [RFC8979] Sarikaya, B., von Hugo, D., and M. Boucadair, "Subscriber
and Performance Policy Identifier Context Headers in the and Performance Policy Identifier Context Headers in the
Network Service Header (NSH)", RFC 8979, Network Service Header (NSH)", RFC 8979,
DOI 10.17487/RFC8979, February 2021, DOI 10.17487/RFC8979, February 2021,
<https://www.rfc-editor.org/info/rfc8979>. <https://www.rfc-editor.org/info/rfc8979>.
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.
Authors' Addresses Authors' Addresses
Yuehua Wei (editor) Yuehua Wei (editor)
ZTE Corporation ZTE Corporation
No.50, Software Avenue No.50, Software Avenue
Nanjing Nanjing
210012 210012
China China
Email: wei.yuehua@zte.com.cn Email: wei.yuehua@zte.com.cn
Uri Elzur Uri Elzur
Intel Intel
Email: uri.elzur@intel.com Email: uri.elzur@intel.com
Sumandra Majee Sumandra Majee
Individual contributor Individual Contributor
Email: Sum.majee@gmail.com Email: Sum.majee@gmail.com
Carlos Pignataro Carlos Pignataro
Cisco Cisco
Email: cpignata@cisco.com Email: cpignata@cisco.com
Donald E. Eastlake Donald E. Eastlake, 3rd
Futurewei Technologies Futurewei Technologies
2386 Panoramic Circle 2386 Panoramic Circle
Apopka, FL 32703 Apopka, FL 32703
United States of America United States of America
Phone: +1-508-333-2270
Email: d3e3e3@gmail.com Email: d3e3e3@gmail.com
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