Networking Working Group L. Ginsberg
Internet-Draft A. Bashandy
Intended status: Standards Track C. Filsfils
Expires: April 2, 2018 Cisco Systems
B. Decraene
Orange
September 29, 2017
IS-IS Extensions to Support Routing over IPv6 Dataplane
draft-bashandy-isis-srv6-extensions-01.txt
Abstract
Segment Routing (SR) allows for a flexible definition of end-to-end
paths by encoding paths as sequences of topological sub-paths, called
"segments". Segment routing architecture can be implemented over an
MPLS data plane as well as an IPv6 data plane. This draft describes
the IS-IS extensions required to support Segment Routing over an IPv6
data plane.
Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119].
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 April 2, 2018.
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Copyright Notice
Copyright (c) 2017 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
(https://trustee.ietf.org/license-info) in effect on the date of
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described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. SRv6-Capabilities sub-TLV . . . . . . . . . . . . . . . . . . 3
2.1. Maximum SL sub-sub-TLV . . . . . . . . . . . . . . . . . 4
2.2. Maximum End Pop SRH sub-sub-TLV . . . . . . . . . . . . . 5
2.3. Maximum T.Insert SRH sub-sub-TLV . . . . . . . . . . . . 5
2.4. Maximum T.Encap SRH sub-sub-TLV . . . . . . . . . . . . . 5
2.5. Maximum End D SRH sub-sub-TLV . . . . . . . . . . . . . . 6
3. SRv6-function Descriptor . . . . . . . . . . . . . . . . . . 6
4. SRv6-SID TLV . . . . . . . . . . . . . . . . . . . . . . . . 9
5. Function Code Points . . . . . . . . . . . . . . . . . . . . 11
6. Advertising SRv6 SIDs associated with a Neighbor . . . . . . 11
6.1. P2P Srv6 X-SID sub-TLV . . . . . . . . . . . . . . . . . 11
6.2. LAN SRv6 X-SID sub-TLV . . . . . . . . . . . . . . . . . 12
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13
7.1. SRv6 SID TLV and sub-TLVs . . . . . . . . . . . . . . . . 14
7.2. IS-IS SRv6-functions Codepoints Registry . . . . . . . . 14
7.3. SRv6 Capabilities sub-TLV . . . . . . . . . . . . . . . . 15
7.4. P2P SRv6 X-SID and LAN SRv6 X-SID sub-TLVs . . . . . . . 15
7.5. IS-IS SRv6 X-SID sub-sub-TLV Codepoints Registry . . . . 16
8. Security Considerations . . . . . . . . . . . . . . . . . . . 16
9. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 16
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 17
10.1. Normative References . . . . . . . . . . . . . . . . . . 18
10.2. Informative References . . . . . . . . . . . . . . . . . 18
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 18
1. Introduction
With Segment Routing (SR)[SRARCH], a node steers a packet through an
ordered list of instructions, called segments.
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Segments are identified through Segment Identifiers (SIDs).
Segment Routing can be directly instantiated on the IPv6 data plane
through the use of the Segment Routing Header defined in [SRH]. SRv6
refers to this SR instantiation on the IPv6 dataplane.
The network programming paradigm [NP] is central to SRv6.
It describes how any function can be bound to a SID and how any
network program can be expressed as a combination of SID's.
It defines several well-known functions such as End, End.X, T.Insert,
T.Encaps, etc.
This document specifies IS-IS extensions that allow IS-IS protocol to
encode some of these functions.
Familiarity with the network programming paradigm [NP] is necessary
to understand the extensions specified in this document.
This document defines one new top level IS-IS_TLV and three new IS-
IS sub-TLVs.
The SRv6 Capabilities sub-TLV announces the ability to support SRv6
and some functions defined in [NP] as well as advertising limitations
when applying such functions.
The SRv6 SID top level TLV, the P2P SRv6 X-SID sub-TLV, and the LAN
SRv6 X-SID sub-TLV are used to advertise which SIDs are instantiated
at a node and what function is bound to each instantiated SID.
Only ISIS-related functions such as End and its variants D and X [NP]
are defined in this document.
2. SRv6-Capabilities sub-TLV
As described in [SRH] and [NP], the list of Segments is stored in the
segment routing header referred hereafter as "SRH".
A router that supports SRv6 MUST be able to process the segment
routing header as described in [SRH] and [NP] up to the limitations
set by the advertised SRv6-capabilities sub-TLV.
To announce this ability, a router uses the newly defined SRv6-
capabilities sub-TLV of the router capabilities TLV [RFC7981]. The
SRv6- capabilities sub-TLV may contain optional sub-sub-TLVs.
The SRv6 Capabilities sub-TLV has the following format:
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Flags |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| sub-sub-TLVs...
Type: Suggested value 22, to be assigned by IANA
Length: 2 + length of sub-sub-TLVs
Flags: 2 octets The following flags are defined:
0 1
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|E| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
where:
E-flag: If set, then router is able to apply "T.Encap"
operation
The following sections define the supported sub-sub-TLVs.
2.1. Maximum SL sub-sub-TLV
The Maximum Segments Left sub-sub-TLV specifies the maximum value of
the "SL" field [SRH] in the SRH of a received packet before applying
the function associated with a SID.
0 1 2
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Max SL |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type: 1
Length: 1
SL Value: 1 octet
An 8 bit unsigned integer.
If the sub-sub-TLV is NOT advertised the value is assumed to be 0.
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2.2. Maximum End Pop SRH sub-sub-TLV
The Maximum End Pop SRH sub-sub-TLV specifies the maximum number of
SIDs in the top SRH in an SRH stack to which the router can apply
"PSP" or USP" [NP] flavors.
0 1 2
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length |Max-End-Pop-SRH|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type: 2
Length: 1
Max-End-Pop-SRH Value: 1 octet
An 8 bit unsigned integer.
If the value is zero or the sub-sub-TLV is NOT advertised,
then it is assumed that the router cannot apply PSP or USP flavors.
2.3. Maximum T.Insert SRH sub-sub-TLV
The Maximum T.Insert SRH sub-sub-TLV specifies the maximum number of
SIDs that can be inserted as part of the "T.insert" behavior [NP].
0 1 2
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Max-T.Insert |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type: 3
Length: 1
Max-T.Insert Value: 1 octet
An 8 bit unsigned integer.
If the value is zero or the sub-sub-TLV is omitted,
then the router is assumed not to support any variation
of the "T.insert" behavior.
2.4. Maximum T.Encap SRH sub-sub-TLV
The Maximum T.Encap SRH sub-sub-TLV specifies the maximum number of
SIDs that can be included as part of the "T.Encap" behavior [NP].
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0 1 2
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Max-T.Encap |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type: 4
Length: 1
Max-T.Encap Value: 1 octet
An 8 bit unsigned integer.
If this value is zero or the sub-sub-TLV is omitted and
the "E" flag is set in the associated SRv6 Capabilities
sub-TLV, then it is assumed that the router can apply T.Encap
by encapsulating the incoming packet in another IPv6 header
without SRH the same way IPinIP encapsulation is performed.
If the "E" flag is clear, then this sub-sub-TLV SHOULD NOT
be transmitted and MUST be ignored on receipt.
2.5. Maximum End D SRH sub-sub-TLV
The Maximum End D SRH sub-sub-TLV specifies the maximum number of
SIDs in an SRH when applying "End.DX6" and "End.DT6" functions.
0 1 2
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Max End D |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type: 5
Length: 1
Max End D Value: 1 octet
An 8 bit unsigned integer.
If this value is zero or the sub-sub-TLV is omitted,
then it is assumed that the router cannot apply
"End.DX6" or "End.DT6" functions if the extension
header right underneath the outer IPv6 header is an SRH.
3. SRv6-function Descriptor
The SRv6 SID TLV defined in Section 4, P2P SRv6 X-SID sub-TLV
specified in Section 6.1, and LAN SRv6 X-SID sub-TLV specified in
section 6.2 MUST include one SRv6 function Descriptor.
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When included in the SRv6 SID TLV, the descriptor is encoded as a
sub-TLV. When included in a P2P/LAN SRv6 X-SID sub-TLV, the
descriptor is encoded as a sub-sub-TLV.
The SRv6-function Descriptor encodes the function (and its flavors)
bound to the SRv6 SID advertised in the SRv6 SID TLV [NP].
The SRv6 SID function Descriptor has the following format:
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0 1
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+-+-+-+-+-+-+-+-+
| Type |
+-+-+-+-+-+-+-+-+
| Length |
+-+-+-+-+-+-+-+-+
| Flags |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Function (2 octets) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type: See IANA considerations in Section 7.
Length: 3
Flags:
0 1 2 3 4 5 6 7
+-+-+-+-+-+-+-+-+
|P|U| Reserved |
+-+-+-+-+-+-+-+-+
This document defines two flags to specify the
flavor(s) [NP] associated with the SRv6 function
specified in the "Function" field:
P bit: If set, then the PSP flavor [NP] is associated with the
function encoded in the "function" field
U bit: If set, then the USP flavor [NP] is associated with the
function encoded in the "function" field
Reserved Bits SHOULD be transmitted as 0 and MUST be ignored on
receipt.
The second two octets encode the function. Function code points
are defined in Section 5.
For a given SRv6 SID function encoded in the "Function" field,
the "P" and "U" bits are set/cleared according to the rules of
enabling/disabling the PSP and USP flavors, respectively, for
that function as specified in [NP].
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4. SRv6-SID TLV
A new top level TLV is introduced to advertise SRv6 Segment
Identifiers (SID) and their attributes.
The new TLV is used to advertise SRv6 SIDs with any of the functions
defined in [NP] whose code point is defined in this document except
those SIDs which must be associated with a particular neighbor in
order to be correctly applied [NP]. SRv6 SIDs associated with a
neighbor are advertised in the sub-TLVs defined in Section 6.
This new TLV shares the sub-TLV space defined for TLVs 135, 235, 236
and 237. The SRv6 SID TLV has the following format:
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | flags | SID-size |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| SID (variable) . . . |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| sub-tlv-len | Sub-TLVs (variable) . . . |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type: 27 (Suggested value to be assigned by IANA)
Length: variable.
One or more SID entries, each of which has the following format:
Flags: 1 octet. The following flags are defined
0
0 1 2 3 4 5 6 7
+-+-+-+-+-+-+-+-+
|D| Reserved |
+-+-+-+-+-+-+-+-+
where:
D bit: When the SID is leaked from level-2 to level-1, the D
bit MUST be set. Otherwise, this bit MUST be clear. SIDs with
the D bit set MUST NOT be leaked from level-1 to level-2. This
is to prevent looping.
The remaining bits are reserved for future use. They SHOULD be
set to zero on transmission and MUST be ignored on receipt.
SID-Size: 1 octet. Number of bits in the SID field.
SID: 1-16 octets. This field encodes the advertised SRv6 SID. The
"SID-size" field can have the values 1-128 and indicates the
number of bits in the SID. The SRv6 SID is encoded in the
minimal number of octets for the given number of bits. The owning
router may associate one or more functions as specified in [NP],
in other documents, or as locally configured.
Sub-TLV-length: 1 octet. Number of octets used by sub-TLVs
The function associated with the advertised SID is specified by
the SRv6-Function Descriptor sub-TLV specified in Section 3.
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5. Function Code Points
This section defines the code points for supported functions
associated with SRv6 SIDs. Functions are defined in [NP].
o 0: Reserved
o 1: End Function
o 2: End.X Function
o 3: End.DX6 Function
o 4: End.DT6 Function
6. Advertising SRv6 SIDs associated with a Neighbor
Certain SRv6 functions [NP] must be associated with a particular
neighbor, and in case of multiple layer 3 links to the same neighbor,
with a particular link in order to be correctly applied.
This document specifies how to advertise two such functions in IS-
IS, namely End.X and End.DX6 [NP].
SIDs associated with End.X and End.DX6 functions are advertised
within neighbor reachability TLVs.
This document defines two new sub-TLVs of TLV 22, 23, 222, 223, and
141 - namely "P2P SRv6 X-SID" and "LAN SRv6 X- SID".
6.1. P2P Srv6 X-SID sub-TLV
This sub-TLV is used to advertise one or more SRv6 SIDs associated
with End.X and End.DX6 [NP] functions over a point to point
adjacency.
The "P2P SRv6 X-SID" sub-TLV has the following format:
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0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Flags | SID-size |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| SID (variable) . . . |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|sub-sub-tlv-len| Sub-sub-TLVs (variable) . . . |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type: 40 (Suggested value to be assigned by IANA)
Length: variable.
One or more SIDs each of which has the following format:
Flags: 1 octet. No flags defined in this document
SID-Size: 1 octet. Number of bits in the SID field.
SID: 1-16 octets. This field encodes the advertised SRv6 SID. The
"SID-size" field can have the values 1-128 and indicates the
number of bits in the SID. The SRv6 SID is encoded in the
minimal number of octets for the given number of bits. The owning
router may associate one or more functions as specified in [NP],
in other documents, or as locally configured.
Sub-sub-TLV-length: 1 octet. Number of octets used by sub-sub-
TLVs
The function associated with the advertised SID is specified by the
SRv6-Function Descriptor sub-sub-TLV specified in Section 3. If the
SRv6-Function Descriptor is encoded in the P2P SRv6 X-SID sub-TLV,
then the encoded SRv6 SID function MUST include only the code points
of SRv6 SID functions that require the specification of a neighbor to
be correctly applied. This document specifies the code points of two
such functions, namely End.X and End.DX6 [NP].
6.2. LAN SRv6 X-SID sub-TLV
This sub-TLV is used to advertise one or more SRv6 SIDs associated
with End.X and End.DX6 [NP] functions over a LAN adjacency. The "LAN
SRv6 X-SID" sub-TLV has the following format:
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | System ID (6 octets) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Flags | SID-size | SID (variable) . . . |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|sub-sub-tlv-len| sub-sub-TLVs (variable) . . . |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type: 41 (Suggested value to be assigned by IANA)
Length: variable.
System-ID: 6 octets of IS-IS System-ID of length "ID Length" as
defined in [ISO10589].
One or more SIDs each of which has the following format:
Flags 1 Octet. No flags are defined in this document
SID-Size: 1 octet. Number of bits in the SID field.
SID: 1-16 octets. This field encodes the advertised SRv6 SID. The
"SID-size" field can have the values 1-128 and indicates the
number of bits in the SID. The SRv6 SID is encoded in the
minimal number of octets for the given number of bits. The owning
router may associate one or more functions as specified in [NP],
in other documents, or as locally configured.
Sub-sub-TLV-length: 1 octet. Number of octets used by sub-sub-
TLVs.
The function associated with the advertised SID is specified by the
SRv6-Function Descriptor sub-sub-TLV specified in Section 3. If the
SRv6-Function Descriptor is encoded in the P2P SRv6 X-SID sub-TLV,
then the encoded SRv6 SID function MUST include only the code points
of SRv6 SID functions that require the specification of a neighbor to
be correctly applied. This document specifies the code points of two
such functions, namely End.X and End.DX6 [NP].
7. IANA Considerations
This documents request allocation for the following TLVs, sub- TLVs,
and sub-sub-TLVs as well updating the ISIS TLV registry and defining
a new registry.
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7.1. SRv6 SID TLV and sub-TLVs
This document adds the following new TLV to the IS-IS TLV Codepoints
registry.
Value: 27 (suggested - to be assigned by IANA)
Name: SRv6 SID
The name of the "Sub-TLVs for TLVs 135, 235, 236 and 237 registry"
needs to be changed to "Sub-TLVs for TLVs 27, 135, 235, 236 and 237
registry".
This document adds a new sub-TLV to the (renamed) "Sub-TLVs for TLVs
27, 135, 235, 236 and 237 registry".
Value: 5 (Suggested - to be assigned by IANA)
Name: SRv6-function Descriptor
The revised table of sub-TLVs in the registry should be:
Type 27 135 235 236 237
1 n y y y y
2 n y y y y
3 y y y y y
4 y y y y y
5(new)y n n n n
11 y y y y y
12 y y y y y
7.2. IS-IS SRv6-functions Codepoints Registry
This document requests the creation of a new IANA managed registry to
identify SRv6 SID functions. The registration procedure is "Expert
Review" as defined in [RFC7370]. Suggested registry name is "SRv6
SID Function Types". A function identifier is an unsigned 8 bit
value. The following values are defined by this document:
0 Reserved
1 End function.
2 End.X function
3 End.DX6 function.
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4 End.DT6 function.
7.3. SRv6 Capabilities sub-TLV
This document adds the definition of a new sub-TLV in the "Sub- TLVs
for TLV 242 registry".
Type: 22 (Suggested - to be assigned by IANA)
Description: SRv6 Capabilities
Thuis document requests the creation of a new IANA managed registry
for sub-sub-TLVs of the SRv6 Capability sub-TLV. The registration
procedure is "Expert Review" as defined in [RFC7370]. Suggested
registry name is "sub-sub-TLVs for SRv6 Capability sub-TLV". The
following sub-TLVs are defined by this document:
0: Reserved
1: Max-SL
2: Max-End-Pop-SRH
3: Max-T-Ins-SRH
4: Max-T-Encap-SRH
5: Max-End-D-SR
7.4. P2P SRv6 X-SID and LAN SRv6 X-SID sub-TLVs
This document adds the definition of two new sub-TLVs in the "sub-
TLVs for TLV 22, 23, 141, 222 and 223 registry".
Type: 40 (suggested - to be assigned by IANA)
Description: Point-to-Point SRv6 X-SID
Type: 41 (suggested - to be assigned by IANA)
Description: LAN SRv6 X-SID
Type 22 23 141 222 223
40 y y y y y
41 y y y y y
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7.5. IS-IS SRv6 X-SID sub-sub-TLV Codepoints Registry
This document requests the creation of a new IANA managed registry to
identify SRv6 SID functions encoded in P2P/LAN X-SID sub-TLVs. The
registration procedure is "Expert Review" as defined in [RFC7370].
Suggested registry name is "SRv6 X-SID sub-sub-TLV Codepoints
Registry". The following values are defined by this document:
Value: 5 (Suggested - to be assigned by IANA)
Name: SRv6-function
Descriptor This sub-sub-TLV MAY appear in either the Point-to-Point
SRv6 X-SID or the LAN SRv6 X-SID sub-TLVs described in Section 7.4.
8. Security Considerations
Security concerns for IS-IS are addressed in [ISO10589, [RFC5304],
and [RFC5310].
9. Contributors
The following people gave a substantial contribution to the content
of this document and should be considered as co-authors:
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Stefano Previdi
Cisco Systems, Inc.
Email: stefano@previdi.net
Peter Psenak
Cisco Systems
Apollo Business Center Mlynske nivy 43
Bratislava 821 09
Slovakia
Email: ppsenak@cisco.com
Paul Wells
Cisco Systems
Saint Paul,
Minnesota
United States
Email: pauwells@cisco.com
Daniel Voyer
Email: daniel.voyer@bell.ca
Satoru Matsushima
Email: satoru.matsushima@g.softbank.co.jp
Bart Peirens
Email: bart.peirens@proximus.com
Hani Elmalky
Email: hani.elmalky@ericsson.com
Prem Jonnalagadda
Email: prem@barefootnetworks.com
Milad Sharif
Email: msharif@barefootnetworks.com>
Robert Hanzl
Cisco Systems
Millenium Plaza Building, V Celnici 10, Prague 1,
Prague, Czech Republic
Email rhanzl@cisco.com
10. References
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10.1. Normative References
[ISO10589]
"Intermediate system to Intermediate system intra-domain
routeing information exchange protocol for use in
conjunction with the protocol for providing the
connectionless-mode Network Service (ISO 8473), ISO/IEC
10589:2002, Second Edition.", Nov 2002.
[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>.
[RFC5304] Li, T. and R. Atkinson, "IS-IS Cryptographic
Authentication", RFC 5304, DOI 10.17487/RFC5304, October
2008, <https://www.rfc-editor.org/info/rfc5304>.
[RFC5310] Bhatia, M., Manral, V., Li, T., Atkinson, R., White, R.,
and M. Fanto, "IS-IS Generic Cryptographic
Authentication", RFC 5310, DOI 10.17487/RFC5310, February
2009, <https://www.rfc-editor.org/info/rfc5310>.
[RFC7370] Ginsberg, L., "Updates to the IS-IS TLV Codepoints
Registry", RFC 7370, DOI 10.17487/RFC7370, September 2014,
<https://www.rfc-editor.org/info/rfc7370>.
[RFC7981] Ginsberg, L., Previdi, S., and M. Chen, "IS-IS Extensions
for Advertising Router Information", RFC 7981,
DOI 10.17487/RFC7981, October 2016,
<https://www.rfc-editor.org/info/rfc7981>.
10.2. Informative References
[NP] "SRv6 Network Programming, draft-filsfils-spring-srv6-
network-programming-01 (work in progress)", June 2017.
[SRARCH] "Segment Routing Architecture, draft-ietf-spring-segment-
routing-12(work in progress)", June 2017.
[SRH] "IPv6 SegmentRouting Header (SRH), draft-ietf-6man-
segment-routing-header-07 (work in progress)", July 2017.
Authors' Addresses
Ginsberg, et al. Expires April 2, 2018 [Page 18]
Internet-Draft draft-bashandy-isis-srv6-extensions September 2017
Les Ginsberg
Cisco Systems
821 Alder Drive
Milpitas, CA 95035
USA
Email: ginsberg@cisco.com
Ahmed Bashandy
Cisco Systems
170 West Tasman Dr
San Jose, CA 95134
USA
Email: bashandy@cisco.com
Clarence Filsfils
Cisco Systems
Brussels
Belgium
Email: cfilsfil@cisco.com
Bruno Decraene
Orange
Issy-les-Moulineaux
France
Email: bruno.decraene@orange.com
Ginsberg, et al. Expires April 2, 2018 [Page 19]