LSR Working Group P. Kaneriya
Internet-Draft T. Li
Intended status: Standards Track A. Przygienda
Expires: 25 August 2025 S. Hegde
Juniper Networks
L. Ginsberg
Cisco Systems
21 February 2025
Multi-Part TLVs in IS-IS
draft-ietf-lsr-multi-tlv-10
Abstract
New technologies are adding new information into IS-IS while
deployment scales are simultaneously increasing, causing the contents
of many critical TLVs to exceed the currently supported limit of 255
octets. Extensions exist that require significant IS-IS changes that
could help address the problem, but a less drastic solution would be
beneficial. This document codifies the common mechanism of extending
the TLV content space through multiple TLVs.
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
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This Internet-Draft will expire on 25 August 2025.
Copyright Notice
Copyright (c) 2025 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 publication of this document.
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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
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Requirements Language . . . . . . . . . . . . . . . . . . . . 4
3. Overview of TLVs . . . . . . . . . . . . . . . . . . . . . . 4
3.1. TLVs Which Advertise a List of Objects . . . . . . . . . 4
3.2. TLVs Which Advertise Objects with Identifier(s) . . . . . 4
3.2.1. Example: Extended IS Reachability . . . . . . . . . . 4
3.2.2. Example: Extended IP Reachability . . . . . . . . . . 5
4. Multi-Part TLVs . . . . . . . . . . . . . . . . . . . . . . . 5
5. Procedure for Receiving Multi-Part TLVs . . . . . . . . . . . 6
6. Specification of Applicability of Multi-Part TLV . . . . . . 7
7. MP-TLV Capability Advertisement . . . . . . . . . . . . . . . 8
8. Deployment Considerations . . . . . . . . . . . . . . . . . . 9
8.1. Recommended Controls and Alarms . . . . . . . . . . . . . 9
8.2. Restrictions on Generation of MP-TLVs . . . . . . . . . . 10
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10
9.1. MP-TLV Support sub-TLV . . . . . . . . . . . . . . . . . 10
9.2. Extension to IS-IS Top Level TLV Registries . . . . . . . 10
9.2.1. MP-TLV for IS-IS Top-Level TLV Codepoints . . . . . . 11
9.2.2. MP-TLV for IS-IS Sub-TLVs for Reverse Metric TLV . . 15
9.2.3. MP-TLV for IS-IS Sub-TLVs for TLVs Advertising Neighbor
Information . . . . . . . . . . . . . . . . . . . . . 15
9.2.4. MP-TLV for IS-IS Sub-TLVs for TLVs Advertising Prefix
Reachability . . . . . . . . . . . . . . . . . . . . 17
9.2.5. MP-TLV for IS-IS Sub-TLVs for MT-Capability TLV . . . 18
9.2.6. MP-TLV for IS-IS Sub-TLVs for IS-IS Router CAPABILITY
TLV . . . . . . . . . . . . . . . . . . . . . . . . . 19
9.2.7. IS-IS Sub-Sub-TLVs for SRv6 Capabilities Sub-TLV . . 21
9.2.8. MP-TLV IS-IS Sub-Sub-TLVs for BIER Info Sub-TLV . . . 21
9.2.9. MP-TLV for IS-IS Sub-TLVs for Segment Identifier/Label
Binding TLVs . . . . . . . . . . . . . . . . . . . . 21
9.2.10. MP-TLV for IS-IS Sub-Sub-TLV Codepoints for
Application-Specific Link Attributes . . . . . . . . 22
9.2.11. MP-TLV for IS-IS Sub-TLVs for Application-Specific SRLG
TLV . . . . . . . . . . . . . . . . . . . . . . . . . 23
9.2.12. MP-TLV for IS-IS Sub-Sub-TLVs for SRv6 SID
Sub-TLVs . . . . . . . . . . . . . . . . . . . . . . 24
9.2.13. MP-TLV for IS-IS Sub-Sub-TLVs for Flexible Algorithm
Definition Sub-TLV . . . . . . . . . . . . . . . . . 24
9.2.14. MP-TLV for IS-IS Sub-Sub-TLVs for Flood Reflection
Discovery Sub-TLV . . . . . . . . . . . . . . . . . . 25
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10. Security Considerations . . . . . . . . . . . . . . . . . . . 25
11. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 25
12. Normative References . . . . . . . . . . . . . . . . . . . . 25
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 27
1. Introduction
The continued growth of the Internet has resulted in a commensurate
growth in the scale of service provider networks and the amount of
information carried in IS-IS [ISO10589] Type-Length-Value (TLV)
tuples. Simultaneously, new traffic engineering technologies are
defining new attributes, further adding to the scaling pressures.
The original TLV definition allows for 255 octets of payload, which
is becoming increasingly stressful.
Some TLV definitions have addressed this by explicitly stating that a
TLV may appear multiple times inside of an LSP. However, this has
not been done for many legacy TLVs, leaving the situation somewhat
ambiguous.
For example, [RFC5305] defines the Extended IS Reachability TLV (22)
and [RFC5120] defines the MT Intermediate Systems TLV (222). These
documents do not specify sending multiple TLVs for the same object
and no other mechanism for expanding the information carrying
capacity of the TLV has been specified.
The intent of this document is to clarify and codify the situation by
explicitly making multiple occurences of a TLV the standard mechanism
for scaling TLV contents. Any future document which proposes a
different mechanism for scaling TLV contents for a given codepoint
MUST provide justification.
This document does not alter the encoding of any TLV where multiple
occurrences of a TLV are already defined. Some examples of this are:
Router Capability TLV (Type 242) [RFC7981]
Application-Specific SRLG (Type 238) [RFC9479]
Instance Identifier (type 7) [RFC8202]
Application-Specific Link Attributes (sub-TLV Type 16) [RFC9479]
[RFC7356] has defined a 16 bit length field for TLVs in flooding
scoped Protocol Data Units (PDUs), but this does not address how to
expand the information advertised when using the existing 8-bit
length TLVs.
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The mechanism described in this document has not been documented for
all TLVs previously, so there is risk that interoperability problems
could occur. This document provides the necessary protocol
definition.
This document specifies a means for extending TLVs where no extension
mechanism has been previously explicitly specified, and defines this
mechanism as the default extension mechanism for future TLVs, if they
choose not to specify another extension mechanism. The mechanism
described in this document is applicable to top level TLVs as well as
any level of sub-TLVs which may appear within a top level TLV.
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. Overview of TLVs
A TLV is a tuple of (Type, Length, Value) and can be advertised in
IS-IS packets. Both Type and Length fields are one octet in size,
which leads to the limitation that a maximum of 255 octets can be
sent in a single TLV.
3.1. TLVs Which Advertise a List of Objects
Some TLVs are simply a list of objects of a given type. For example,
the BFD-Enabled TLV (type 148) [RFC6213] contains a list of Multi-
Topology Identifier (MTID)/ Network Layer Protocol Identifier (NLPID)
pairs. If more than 255 octets is required to advertise all of the
MTID/NLPID pairs, multiple BFD-Enabled TLVs would be required. The
relationship between multiple BFD-Enabled TLVs is established using
the TLV type.
3.2. TLVs Which Advertise Objects with Identifier(s)
Some TLVs support advertisement of objects of a given type, where
each object is identified by a unique set of identifiers. In this
case the "key" which uniquely identifies a given object consists of
the set of identifiers.
3.2.1. Example: Extended IS Reachability
As an example, consider the Extended IS Reachability TLV (type 22).
A neighbor in this TLV is specified by:
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* 7 octets of system ID and pseudonode number
* 3 octets of default metric
* Optionally one or more of the following link identifiers:
- IPv4 interface address and IPv4 neighbor address as specified
in [RFC5305]
- IPv6 interface address and IPv6 neighbor address as specified
in [RFC6119]
- Link Local/Remote Identifiers as specified in [RFC5307]
The key consists of the 7 octets of system ID and pseudonode number
plus the set of link identifiers which are present.
3.2.2. Example: Extended IP Reachability
As another example, consider the Extended IP Reachability TLV (type
135) [RFC5305]. A prefix in this TLV is specified by:
* 4 octets of metric information
* 1 octet of control information which includes 6 bits specifying
the prefix length
* 0-4 octets of IPv4 prefix
followed by up to 250 octets of sub-TLV information.
The key consists of the 6 bits of prefix length plus 0-4 octets of
IPv4 prefix.
4. Multi-Part TLVs
If a router advertises multiple TLV tuples with the same TLV type and
the same key (when applicable) in an IS-IS Hello (IIH) packet or in
the set of LSPs for a given level, they are considered a Multi-Part
TLV (MP-TLV).
In the absence of MP-TLV support, when a router receives an MP-TLV,
the receiver chooses which TLV will be processed and which TLV will
be ignored. Note that this can occur either legitimately as a
transient when a TLV moves from one LSP to another or as a result of
a defect in the sending implementation.
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In the presence of MP-TLV support, when a router receives an MP-TLV,
information from all the TLVs is processed.
The encoding of TLVs is not altered by the introduction of MP-TLV
support. In particular, the "key" which is used to identify the set
of TLVs which form an MP-TLV is the same key used in the absence of
MP-TLV support. Also note the definition of the "key" exists in the
specification(s) which define the TLV.
NOTE: This document intentionally does not include a definition of
the key for each codepoint. To do so would be redundant and risk
unintentionally deviating from the definition which already exists in
the relevant specifications.
Each TLV that is part of an MP-TLV MUST be parsable independent of
other TLVs in the MP-TLV. Breaking of a single sub-TLV or other data
unit across TLVs MUST NOT be done.
5. Procedure for Receiving Multi-Part TLVs
A node that receives a Multi-Part TLV MUST accept all of the
information in all of the parts. The order of arrival and placement
of the TLV parts in LSP fragments is irrelevant. Multiple TLV parts
MAY occur in a single LSP or parts MAY occur in different LSPs.
The placement of the TLV parts in an IIH is irrelevant.
When processing MP-TLVs, implementations MUST NOT impose a minimum
length check. Although MP-TLVs SHOULD NOT be sent unless the
capacity of a single TLV (255 octets) is exceeded, receivers MUST NOT
reject MP-TLVs if senders do not strictly adhere to this constraint.
For example, if two MP-TLVs are received, each of which has a length
of 100 bytes, the fact that the total amount of data does not exceed
255 bytes MUST NOT cause the TLVs to be rejected. See Section 8.2
for guidance when sending MP-TLVs.
The contents of a Multi-Part TLV MUST be processed as if they were
concatenated. If the internals of the TLV contain key information,
then replication of the key information MUST be taken to indicate
that subsequent data MUST be processed as if the subsequent data were
concatenated after a single copy of the key information.
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For example, suppose that a node receives an LSP with a Multi-Part
Extended IS Reachability TLV. The first part contains key
information K with sub-TLVs A, B, and C. The second part contains
key information K with sub-TLVs D, E, and F. The receiving node must
then process this as having key information K and sub-TLVs A, B, C,
D, E, F, or, because ordering is irrelevant, sub-TLVs D, E, F, A, B,
C, or any other permutation.
A TLV may contain information in its fixed part that is not part of
the key. For example, the metric in both the Extended IS
Reachability TLV and the Extended IP Reachability TLV does not
specify which object the TLV refers to, and thus is not part of the
key. Having inconsistent information in different parts of a MP-TLV
is an error.
It is also possible that information which is not part of the fixed
part of a TLV can be duplicated e.g., a sub-TLV which is intended to
only appear once appears multiple times and has inconsistent values.
This could occur within the same TLV or in different parts of an MP-
TLV. This is also an error.
Specifying how to handle such cases is the responsibility of the
document which defines the TLV. If such a document is not explicit
in how to handle such cases, it is RECOMMENDED that the first
occurrence in the lowest numbered LSP be used. In the case of IIHs,
it is RECOMMENDED that the first occurrence in the IIH be used.
6. Specification of Applicability of Multi-Part TLV
As mentioned in Section 1, existing specifications for some TLVs have
explicitly stated that the use of Multi-Part TLV procedures are
applicable to that codepoint. However, Multi-Part TLV procedures are
potentially applicable to any codepoint that allows sub-TLVs to be
included as part of the information advertised. Multi-Part
procedures may also be applicable to codepoints which do not support
sub-TLVs, but which define an unbounded number of attributes which
may be advertised in a single codepoint. An example of the latter is
GMPLS-SRLG as defined in [RFC5307].
The lack of explicit indication of applicability of Multi-Part TLV
procedures to all codepoints to which such procedures could be
applied contributes to potential interoperability problems if/when
the need arises to advertise more than 255 octets of information for
such a codepoint.
This document makes explicit the applicability of Multi-Part TLV
procedures for all existing codepoints defined for the IS-IS protocol
by extending existing and relevant IANA protocol registries to
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include an explicit indication of applicability of Multi-Part TLV
procedures for each codepoint. See Section 9. This guarantees that
any new codepoints defined by future protocol extensions will
explicitly indicate the applicability of Multi-Part TLV procedures to
the new codepoints.
7. MP-TLV Capability Advertisement
Introduction of the use of MP-TLV for codepoints where the existing
specifications have not explicitly defined MP-TLV support can be
extremely disruptive to network operations in cases where not all
nodes in the network support MP-TLV for those codepoints. Partial
deployment can easily result in traffic loss and/or other unexpected
behaviors which may be hard to diagnose.
As an aid to network operators when disgnosing such situations, a new
sub-TLV of the IS-IS Router CAPABILITY TLV [RFC7981] is defined:
MP-TLV Support for TLVs with implicit support
Type 30 (suggested - to be assigned by IANA) 1 octet
Length 0 1 octet
Nodes which support MP-TLV for codepoints for which existing
specifications do not explicitly define such support, but for which
MP-TLV is applicable, SHOULD include this sub-TLV in a Router
Capability TLV.
Scope of the associated Router Capability TLV is per level (S-bit
clear).
This advertisement is for informational purposes only.
Implementations MUST NOT alter what is sent or how what is received
is processed based on these advertisements.
The sub-TLV intentionally does not provide a syntax to specify MP-TLV
support on a per-codepoint basis. It is presumed that if such
support is provided that it applies to all relevant codepoints. It
is understood that in reality, a given implementation might limit MP-
TLV support to particular codepoints based on the needs of the
deployment scenarios in which it is used. Therefore, diligence is
still required on the part of the operator to ensure that
configurations which require the sending of MP-TLV for a given
codepoint are not introduced on any node in the network until all
nodes in the network support MP-TLV for the relevant codepoints.
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The Router Capability TLV is meant to advertise capabilities which
are of direct use to the IS-IS protocol. The MP-TLV Support sub-TLV
advertises management information, not of direct use to the protocol.
The intent is to provide information which may be of use to a network
operator. This exception to the intended use of the Router
Capability TLV is introduced to help mitigate the potential
disruptiveness associated with the introduction of MP-TLV support in
cases where such support has not been explicitly defined. This is
not intended to introduce a generic new use case for the Router
Capability TLV.
Note that with the introduction of explicit specification of MP-TLV
applicability for codepoints (see Section 9), implicit MP-TLV support
will never occur in the future. Where MP-TLV support is explicitly
defined, conformant implementations MUST support MP-TLV.
8. Deployment Considerations
Sending of MP-TLVs in the presence of nodes which do not correctly
process such advertisements can result in interoperablity issues,
including incorrect forwarding of packets. This section discusses
best practices which SHOULD be used when a deployment requires the
use of MP-TLVs for codepoints for which existing specifications do
not explicitly indicate MP-TLV support.
While it is not in scope for this document to mandate how
implementations provide the means to prevent (or at least make less
likely) partial deployment of MP-TLV for a given codepoint, it is
important to emphasize the need to assist operators in avoiding
inadvertent problematic deployment scenarios. Providing appropriate
controls to enable/disable the sending of MP-TLVs as discussed in
Section 8.1 is important to avoid interoperability issues.
Network operators SHOULD NOT enable Multi-Part TLVs until ensuring
that all implementations that will receive the Multi-Part TLVs are
capable of interpreting them correctly as described in Section 5.
8.1. Recommended Controls and Alarms
It is RECOMMENDED that implementations which support the sending of
MP-TLVs provide configuration controls to enable/disable generation
of MP-TLVs. Given that MP-TLV support in a given implementation may
vary on a per TLV basis, these controls SHOULD support per codepoint
granularity. For example, an implementation might support MP-TLVs
for IS Extended Reachability but not for IP Reachability.
Implementations which support disablement of MP-TLVs MUST report
alarms under the following conditions:
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* If an MP-TLV is received when use of MP-TLVs is disabled.
* If local LSP generation requires the use of MP-TLVs when
generation of MP-TLVs is disabled.
8.2. Restrictions on Generation of MP-TLVs
This section discusses restrictions on sending of MP-TLVs. When
applying these restrictions it is assumed that it has already been
determined that sending of MP-TLVs is allowed based on the setting of
the controls discussed in Section 8.1.
Sending a single TLV with all the information about an object is
preferable to sending multiple TLVs. It is simpler and more
efficient to parse information from a single TLV than to combine the
information from multiple TLVs. Implementations SHOULD NOT send
multiple TLVs unless MP-TLV is applicable to the TLV and the amount
of information which is required to be sent exceeds the capacity of a
single TLV. For example, when additional space is required in an
existing TLV, as long as there is space in the TLV, information
SHOULD NOT be split into multiple TLVs. If there is no space in the
current LSP to fit the now larger TLV, the TLV SHOULD be moved to a
new LSP.
9. IANA Considerations
9.1. MP-TLV Support sub-TLV
This document requests the following code point from the "IS-IS Sub-
TLVs for IS-IS Router CAPABILITY TLV" registry:
Type: 30 (suggested)
Description: MP-TLV Support for TLVs with implicit support
MP-TLV Applicability: N
Reference: This document Section 7.2
9.2. Extension to IS-IS Top Level TLV Registries
This document requests that IANA extend a number of registries under
the "IS-IS TLV Codepoints" registries to include a column that
indicates whether the MP-TLV procedures described in this document
are applicable to that codepoint. "Y" indicates that MP-TLV is
applicable. "N" indicates MP-TLV is not applicable.
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The following sub-sections provide the initial contents of the new
column for a number of existing registries. The initial values for
MP-TLV applicability defined in the following sub-sections are based
on the rule that MP-TLV is applicable to any codepoint which supports
sub-TLVs, without regard to whether the sub-TLVs which are currently
defined are sufficient to require MP-TLVs to be sent.
9.2.1. MP-TLV for IS-IS Top-Level TLV Codepoints
+===========+========================================+====+
| Value | Name | MP |
+===========+========================================+====+
| 0 | Reserved | |
+-----------+----------------------------------------+----+
| 1 | Area Addresses | N |
+-----------+----------------------------------------+----+
| 2 | IIS Neighbors | N |
+-----------+----------------------------------------+----+
| 3 | ES Neighbors | N |
+-----------+----------------------------------------+----+
| 4 | Part. DIS | N |
+-----------+----------------------------------------+----+
| 5 | Prefix Neighbors | N |
+-----------+----------------------------------------+----+
| 6 | IIS Neighbors | N |
+-----------+----------------------------------------+----+
| 7 | Instance Identifier | Y |
+-----------+----------------------------------------+----+
| 8 | Padding | N |
+-----------+----------------------------------------+----+
| 9 | LSP Entries | N |
+-----------+----------------------------------------+----+
| 10 | Authentication | N |
+-----------+----------------------------------------+----+
| 11 | ESN TLV | N |
+-----------+----------------------------------------+----+
| 12 | Opt. Checksum | N |
+-----------+----------------------------------------+----+
| 13 | Purge Originator Identification | N |
+-----------+----------------------------------------+----+
| 14 | LSPBufferSize | N |
+-----------+----------------------------------------+----+
| 15 | Router-Fingerprint | N |
+-----------+----------------------------------------+----+
| 16 | Reverse Metric | N |
+-----------+----------------------------------------+----+
| 17 | IS-IS Area Node IDs TLV | N |
+-----------+----------------------------------------+----+
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| 18 | IS-IS Flooding Path TLV | N |
+-----------+----------------------------------------+----+
| 19 | IS-IS Flooding Request TLV | N |
+-----------+----------------------------------------+----+
| 20 | Area Proxy | N |
+-----------+----------------------------------------+----+
| 21 | Flooding Parameters TLV | N |
+-----------+----------------------------------------+----+
| 22 | Extended IS reachability | Y |
+-----------+----------------------------------------+----+
| 23 | IS Neighbor Attribute | Y |
+-----------+----------------------------------------+----+
| 24 | IS Alias ID | N |
+-----------+----------------------------------------+----+
| 25 | L2 Bundle Member Attributes | Y |
+-----------+----------------------------------------+----+
| 26 | Unassigned | |
+-----------+----------------------------------------+----+
| 27 | SRv6 Locator | Y |
+-----------+----------------------------------------+----+
| 28 | Zone ID | N |
+-----------+----------------------------------------+----+
| 29-41 | Unassigned | |
+-----------+----------------------------------------+----+
| 42 | DECnet Phase IV | N |
+-----------+----------------------------------------+----+
| 43-65 | Unassigned | |
+-----------+----------------------------------------+----+
| 66 | Lucent Proprietary | N |
+-----------+----------------------------------------+----+
| 67-125 | Unassigned | |
+-----------+----------------------------------------+----+
| 126 | IPv4 Algorithm Prefix Reachability TLV | N |
+-----------+----------------------------------------+----+
| 127 | IPv6 Algorithm Prefix Reachability TLV | N |
+-----------+----------------------------------------+----+
| 128 | IP Int. Reach | N |
+-----------+----------------------------------------+----+
| 129 | Prot. Supported | N |
+-----------+----------------------------------------+----+
| 130 | IP Ext. Address | N |
+-----------+----------------------------------------+----+
| 131 | IDRPI | N |
+-----------+----------------------------------------+----+
| 132 | IP Intf. Address | N |
+-----------+----------------------------------------+----+
| 133 | Illegal | N |
+-----------+----------------------------------------+----+
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| 134 | Traffic Engineering router ID | N |
+-----------+----------------------------------------+----+
| 135 | Extended IP reachability | Y |
+-----------+----------------------------------------+----+
| 136 | Unassigned | |
+-----------+----------------------------------------+----+
| 137 | Dynamic Name | N |
+-----------+----------------------------------------+----+
| 138 | GMPLS-SRLG | Y |
+-----------+----------------------------------------+----+
| 139 | IPv6 SRLG | N |
+-----------+----------------------------------------+----+
| 140 | IPv6 TE Router ID | N |
+-----------+----------------------------------------+----+
| 141 | inter-AS reachability information | Y |
+-----------+----------------------------------------+----+
| 142 | GADDR-TLV | Y |
+-----------+----------------------------------------+----+
| 143 | MT-Port-Cap-TLV | Y |
+-----------+----------------------------------------+----+
| 144 | MT-Capability TLV | Y |
+-----------+----------------------------------------+----+
| 145 | TRILL Neighbor TLV | N |
+-----------+----------------------------------------+----+
| 146 | Unassigned | |
+-----------+----------------------------------------+----+
| 147 | MAC-RI TLV | Y |
+-----------+----------------------------------------+----+
| 148 | BFD-Enabled TLV | Y |
+-----------+----------------------------------------+----+
| 149 | Segment Identifier / Label Binding | Y |
+-----------+----------------------------------------+----+
| 150 | Multi-Topology Segment Identifier / | Y |
| | Label Binding | |
+-----------+----------------------------------------+----+
| 151-160 | Unassigned | |
+-----------+----------------------------------------+----+
| 161 | Flood Reflection | N |
+-----------+----------------------------------------+----+
| 162-175 | Unassigned | |
+-----------+----------------------------------------+----+
| 176 | Nortel Proprietary | N |
+-----------+----------------------------------------+----+
| 177 | Nortel Proprietary | N |
+-----------+----------------------------------------+----+
| 178-210 | Unassigned | |
+-----------+----------------------------------------+----+
| 211 | Restart TLV | N |
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+-----------+----------------------------------------+----+
| 212-221 | Unassigned | |
+-----------+----------------------------------------+----+
| 222 | MT-ISN | Y |
+-----------+----------------------------------------+----+
| 223 | MT IS Neighbor Attribute | Y |
+-----------+----------------------------------------+----+
| 224-228 | Unassigned | |
+-----------+----------------------------------------+----+
| 229 | M-Topologies | N |
+-----------+----------------------------------------+----+
| 230-231 | Unassigned | |
+-----------+----------------------------------------+----+
| 232 | IPv6 Intf. Addr. | N |
+-----------+----------------------------------------+----+
| 233 | IPv6 Global Interface Address TLV | N |
+-----------+----------------------------------------+----+
| 234 | Unassigned | |
+-----------+----------------------------------------+----+
| 235 | MT IP. Reach | Y |
+-----------+----------------------------------------+----+
| 236 | IPv6 IP. Reach | Y |
+-----------+----------------------------------------+----+
| 237 | MT IPv6 IP. Reach | Y |
+-----------+----------------------------------------+----+
| 238 | Application-Specific SRLG | Y |
+-----------+----------------------------------------+----+
| 239 | Unassigned | |
+-----------+----------------------------------------+----+
| 240 | P2P 3-Way Adj. State | N |
+-----------+----------------------------------------+----+
| 241 | Unassigned | |
+-----------+----------------------------------------+----+
| 242 | IS-IS Router CAPABILITY TLV | Y |
+-----------+----------------------------------------+----+
| 243 | Scope Flooding Support | N |
+-----------+----------------------------------------+----+
| 244-250 | Unassigned | |
+-----------+----------------------------------------+----+
| 251 | Generic Information | Y |
+-----------+----------------------------------------+----+
| 252-65535 | Unassigned | |
+-----------+----------------------------------------+----+
Table 1: IS-IS Top-Level TLV Codepoints
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9.2.2. MP-TLV for IS-IS Sub-TLVs for Reverse Metric TLV
+========+============================+====+
| Value | Name | MP |
+========+============================+====+
| 0 | Reserved | |
+--------+----------------------------+----+
| 1-17 | Unassigned | |
+--------+----------------------------+----+
| 18 | Traffic Engineering Metric | N |
+--------+----------------------------+----+
| 19-255 | Unassigned | |
+--------+----------------------------+----+
Table 2: IS-IS Sub-TLVs for Reverse
Metric TLV
9.2.3. MP-TLV for IS-IS Sub-TLVs for TLVs Advertising Neighbor
Information
+=========+===================================================+====+
| Value | Name | MP |
+=========+===================================================+====+
| 0-2 | Unassigned | |
+---------+---------------------------------------------------+----+
| 3 | Administrative group (color) | N |
+---------+---------------------------------------------------+----+
| 4 | Link Local/Remote Identifiers | N |
+---------+---------------------------------------------------+----+
| 5 | Unassigned | |
+---------+---------------------------------------------------+----+
| 6 | IPv4 interface address | N |
+---------+---------------------------------------------------+----+
| 7 | Unassigned | |
+---------+---------------------------------------------------+----+
| 8 | IPv4 neighbor address | N |
+---------+---------------------------------------------------+----+
| 9 | Maximum link bandwidth | N |
+---------+---------------------------------------------------+----+
| 10 | Maximum reservable link bandwidth | N |
+---------+---------------------------------------------------+----+
| 11 | Unreserved bandwidth | N |
+---------+---------------------------------------------------+----+
| 12 | IPv6 Interface Address | N |
+---------+---------------------------------------------------+----+
| 13 | IPv6 Neighbor Address | N |
+---------+---------------------------------------------------+----+
| 14 | Extended Administrative Group | N |
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+---------+---------------------------------------------------+----+
| 15 | Link MSD | Y |
+---------+---------------------------------------------------+----+
| 16 | Application-Specific Link Attributes | Y |
+---------+---------------------------------------------------+----+
| 17 | Generic Metric | N |
+---------+---------------------------------------------------+----+
| 18 | TE Default metric | N |
+---------+---------------------------------------------------+----+
| 19 | Link-attributes | N |
+---------+---------------------------------------------------+----+
| 20 | Link Protection Type | N |
+---------+---------------------------------------------------+----+
| 21 | Interface Switching Capability Descriptor | Y |
+---------+---------------------------------------------------+----+
| 22 | Bandwidth Constraints | N |
+---------+---------------------------------------------------+----+
| 23 | Unconstrained TE LSP Count (sub-)TLV | N |
+---------+---------------------------------------------------+----+
| 24 | Remote AS Number | N |
+---------+---------------------------------------------------+----+
| 25 | IPv4 Remote ASBR Identifier | N |
+---------+---------------------------------------------------+----+
| 26 | IPv6 Remote ASBR Identifier | N |
+---------+---------------------------------------------------+----+
| 27 | Interface Adjustment Capability Descriptor (IACD) | Y |
+---------+---------------------------------------------------+----+
| 28 | MTU | N |
+---------+---------------------------------------------------+----+
| 29 | SPB-Metric | N |
+---------+---------------------------------------------------+----+
| 30 | SPB-A-OALG | Y |
+---------+---------------------------------------------------+----+
| 31 | Adjacency Segment Identifier | N |
+---------+---------------------------------------------------+----+
| 32 | LAN Adjacency Segment Identifier | N |
+---------+---------------------------------------------------+----+
| 33 | Unidirectional Link Delay | N |
+---------+---------------------------------------------------+----+
| 34 | Min/Max Unidirectional Link Delay | N |
+---------+---------------------------------------------------+----+
| 35 | Unidirectional Delay Variation | N |
+---------+---------------------------------------------------+----+
| 36 | Unidirectional Link Loss | N |
+---------+---------------------------------------------------+----+
| 37 | Unidirectional Residual Bandwidth | N |
+---------+---------------------------------------------------+----+
| 38 | Unidirectional Available Bandwidth | N |
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+---------+---------------------------------------------------+----+
| 39 | Unidirectional Utilized Bandwidth | N |
+---------+---------------------------------------------------+----+
| 40 | RTM Capability | N |
+---------+---------------------------------------------------+----+
| 41 | L2 Bundle Member Adj-SID | Y |
+---------+---------------------------------------------------+----+
| 42 | L2 Bundle Member LAN Adj-SID | Y |
+---------+---------------------------------------------------+----+
| 43 | SRv6 End.X SID | Y |
+---------+---------------------------------------------------+----+
| 44 | SRv6 LAN End.X SID | Y |
+---------+---------------------------------------------------+----+
| 45 | IPv6 Local ASBR Identifier | N |
+---------+---------------------------------------------------+----+
| 46-160 | Unassigned | |
+---------+---------------------------------------------------+----+
| 161 | Flood Reflector Adjacency | N |
+---------+---------------------------------------------------+----+
| 162-249 | Unassigned | |
+---------+---------------------------------------------------+----+
| 250-254 | Reserved for Cisco-specific extensions | |
+---------+---------------------------------------------------+----+
| 255 | Reserved for future expansion | |
+---------+---------------------------------------------------+----+
Table 3: IS-IS Sub-TLVs for TLVs Advertising Neighbor Information
9.2.4. MP-TLV for IS-IS Sub-TLVs for TLVs Advertising Prefix
Reachability
+========+=========================================+====+
| Value | Name | MP |
+========+=========================================+====+
| 0 | Unassigned | |
+--------+-----------------------------------------+----+
| 1 | 32-bit Administrative Tag Sub-TLV | Y |
+--------+-----------------------------------------+----+
| 2 | 64-bit Administrative Tag Sub-TLV | Y |
+--------+-----------------------------------------+----+
| 3 | Prefix Segment Identifier | N |
+--------+-----------------------------------------+----+
| 4 | Prefix Attribute Flags | N |
+--------+-----------------------------------------+----+
| 5 | SRv6 End SID | Y |
+--------+-----------------------------------------+----+
| 6 | Flexible Algorithm Prefix Metric (FAPM) | N |
+--------+-----------------------------------------+----+
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| 7-10 | Unassigned | |
+--------+-----------------------------------------+----+
| 11 | IPv4 Source Router ID | N |
+--------+-----------------------------------------+----+
| 12 | IPv6 Source Router ID | N |
+--------+-----------------------------------------+----+
| 13-31 | Unassigned | |
+--------+-----------------------------------------+----+
| 32 | BIER Info | Y |
+--------+-----------------------------------------+----+
| 32-255 | Unassigned | |
+--------+-----------------------------------------+----+
Table 4: IS-IS Sub-TLVs for TLVs Advertising Prefix
Reachability
9.2.5. MP-TLV for IS-IS Sub-TLVs for MT-Capability TLV
+========+==============================+====+
| Value | Name | MP |
+========+==============================+====+
| 0 | Reserved | |
+--------+------------------------------+----+
| 1 | SPB-Inst | N |
+--------+------------------------------+----+
| 2 | SPB-I-OALG | Y |
+--------+------------------------------+----+
| 3 | SPBM-SI | Y |
+--------+------------------------------+----+
| 4 | SPBV-ADDR | Y |
+--------+------------------------------+----+
| 5 | Unassigned | |
+--------+------------------------------+----+
| 6 | NICKNAME | Y |
+--------+------------------------------+----+
| 7 | TREES | N |
+--------+------------------------------+----+
| 8 | TREE-RT-IDs | Y |
+--------+------------------------------+----+
| 9 | TREE-USE-IDs | Y |
+--------+------------------------------+----+
| 10 | INT-VLAN | Y |
+--------+------------------------------+----+
| 11-12 | Unassigned | |
+--------+------------------------------+----+
| 13 | TRILL-VER | N |
+--------+------------------------------+----+
| 14 | VLAN-GROUP | Y |
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+--------+------------------------------+----+
| 15 | INT-LABEL | Y |
+--------+------------------------------+----+
| 16 | RBCHANNELS | Y |
+--------+------------------------------+----+
| 17 | AFFINITY | Y |
+--------+------------------------------+----+
| 18 | LABEL-GROUP | Y |
+--------+------------------------------+----+
| 19-20 | Unassigned | |
+--------+------------------------------+----+
| 21 | Topology sub-TLV | Y |
+--------+------------------------------+----+
| 22 | Hop sub-TLV | N |
+--------+------------------------------+----+
| 23 | Bandwidth Constraint sub-TLV | N |
+--------+------------------------------+----+
| 24 | Bandwidth Assignment sub-TLV | N |
+--------+------------------------------+----+
| 25 | Timestamp sub-TLV | N |
+--------+------------------------------+----+
| 26-254 | Unassigned | |
+--------+------------------------------+----+
| 255 | Reserved | |
+--------+------------------------------+----+
Table 5: IS-IS Sub-TLVs for MT-Capability TLV
9.2.6. MP-TLV for IS-IS Sub-TLVs for IS-IS Router CAPABILITY TLV
+=========+====================================+====+
| Value | Name | MP |
+=========+====================================+====+
| 0 | Reserved | |
+---------+------------------------------------+----+
| 1 | TE Node Capability Descriptor | N |
+---------+------------------------------------+----+
| 2 | Segment Routing Capability | N |
+---------+------------------------------------+----+
| 3 | TE-MESH-GROUP TLV (IPv4) | Y |
+---------+------------------------------------+----+
| 4 | TE-MESH-GROUP TLV (IPv6) | Y |
+---------+------------------------------------+----+
| 5 | PCED sub-TLV | N |
+---------+------------------------------------+----+
| 6 | NICKNAME | Y |
+---------+------------------------------------+----+
| 7 | TREES | N |
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+---------+------------------------------------+----+
| 8 | TREE-RT-IDs | Y |
+---------+------------------------------------+----+
| 9 | TREE-USE-IDs | Y |
+---------+------------------------------------+----+
| 10 | INT-VLAN | Y |
+---------+------------------------------------+----+
| 11 | IPv4 TE Router ID | N |
+---------+------------------------------------+----+
| 12 | IPv6 TE Router ID | N |
+---------+------------------------------------+----+
| 13 | TRILL-VER | N |
+---------+------------------------------------+----+
| 14 | VLAN-GROUP | Y |
+---------+------------------------------------+----+
| 15 | INT-LABEL | Y |
+---------+------------------------------------+----+
| 16 | RBCHANNELS | Y |
+---------+------------------------------------+----+
| 17 | AFFINITY | Y |
+---------+------------------------------------+----+
| 18 | LABEL-GROUP | Y |
+---------+------------------------------------+----+
| 19 | Segment Routing Algorithm | N |
+---------+------------------------------------+----+
| 20 | S-BFD Discriminators | N |
+---------+------------------------------------+----+
| 21 | Node-Admin-Tag | N |
+---------+------------------------------------+----+
| 22 | Segment Routing Local Block (SRLB) | N |
+---------+------------------------------------+----+
| 23 | Node MSD | Y |
+---------+------------------------------------+----+
| 24 | Segment Routing Mapping Server | N |
| | Preference (SRMS Preference) | |
+---------+------------------------------------+----+
| 25 | SRv6 Capabilities | N |
+---------+------------------------------------+----+
| 26 | Flexible Algorithm Definition | N |
| | (FAD) | |
+---------+------------------------------------+----+
| 27 | IS-IS Area Leader Sub-TLV | N |
+---------+------------------------------------+----+
| 28 | IS-IS Dynamic Flooding Sub-TLV | N |
+---------+------------------------------------+----+
| 29 | IP Algorithm Sub-TLV | N |
+---------+------------------------------------+----+
| 30-160 | Unassigned | |
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+---------+------------------------------------+----+
| 161 | Flood Reflection Discovery | Y |
+---------+------------------------------------+----+
| 162-255 | Unassigned | |
+---------+------------------------------------+----+
Table 6: IS-IS Sub-TLVs for IS-IS Router
CAPABILITY TLV
9.2.7. IS-IS Sub-Sub-TLVs for SRv6 Capabilities Sub-TLV
+=======+============+====+
| Value | Name | MP |
+=======+============+====+
| 0 | Reserved | |
+-------+------------+----+
| 1-255 | Unassigned | |
+-------+------------+----+
Table 7: IS-IS Sub-Sub-
TLVs for SRv6
Capabilities Sub-TLV
9.2.8. MP-TLV IS-IS Sub-Sub-TLVs for BIER Info Sub-TLV
+=======+=========================+====+
| Value | Name | MP |
+=======+=========================+====+
| 0 | Unassigned | |
+-------+-------------------------+----+
| 1 | BIER MPLS Encapsulation | N |
+-------+-------------------------+----+
| 2-255 | Unassigned | |
+-------+-------------------------+----+
Table 8: IS-IS Sub-Sub-TLVs for BIER
Info Sub-TLV
9.2.9. MP-TLV for IS-IS Sub-TLVs for Segment Identifier/Label Binding
TLVs
+=======+===========================+====+
| Value | Name | MP |
+=======+===========================+====+
| 0 | Reserved | |
+-------+---------------------------+----+
| 1 | SID/Label | N |
+-------+---------------------------+----+
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| 2 | Unassigned | |
+-------+---------------------------+----+
| 3 | Prefix Segment Identifier | N |
+-------+---------------------------+----+
| 4-255 | Unassigned | |
+-------+---------------------------+----+
Table 9: IS-IS Sub-TLVs for Segment
Identifier/Label Binding TLVs
9.2.10. MP-TLV for IS-IS Sub-Sub-TLV Codepoints for Application-
Specific Link Attributes
+========+====================================+====+
| Value | Name | MP |
+========+====================================+====+
| 0-2 | Unassigned | |
+--------+------------------------------------+----+
| 3 | Administrative group (color) | N |
+--------+------------------------------------+----+
| 4-8 | Unassigned | |
+--------+------------------------------------+----+
| 9 | Maximum link bandwidth | N |
+--------+------------------------------------+----+
| 10 | Maximum reservable link bandwidth | N |
+--------+------------------------------------+----+
| 11 | Unreserved bandwidth | N |
+--------+------------------------------------+----+
| 12-13 | Unassigned | |
+--------+------------------------------------+----+
| 14 | Extended Administrative Group | N |
+--------+------------------------------------+----+
| 15-16 | Unassigned | |
+--------+------------------------------------+----+
| 17 | Generic Metric | Y |
+--------+------------------------------------+----+
| 18 | TE Default Metric | N |
+--------+------------------------------------+----+
| 19-32 | Unassigned | |
+--------+------------------------------------+----+
| 33 | Unidirectional Link Delay | N |
+--------+------------------------------------+----+
| 34 | Min/Max Unidirectional Link Delay | N |
+--------+------------------------------------+----+
| 35 | Unidirectional Delay Variation | N |
+--------+------------------------------------+----+
| 36 | Unidirectional Link Loss | N |
+--------+------------------------------------+----+
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| 37 | Unidirectional Residual Bandwidth | N |
+--------+------------------------------------+----+
| 38 | Unidirectional Available Bandwidth | N |
+--------+------------------------------------+----+
| 39 | Unidirectional Utilized Bandwidth | N |
+--------+------------------------------------+----+
| 40-255 | Unassigned | |
+--------+------------------------------------+----+
Table 10: IS-IS Sub-Sub-TLV Codepoints for
Application-Specific Link Attributes
9.2.11. MP-TLV for IS-IS Sub-TLVs for Application-Specific SRLG TLV
+========+===============================+====+
| Value | Name | MP |
+========+===============================+====+
| 0-3 | Unassigned | |
+--------+-------------------------------+----+
| 4 | Link Local/Remote Identifiers | N |
+--------+-------------------------------+----+
| 5 | Unassigned | |
+--------+-------------------------------+----+
| 6 | IPv4 interface address | N |
+--------+-------------------------------+----+
| 7 | Unassigned | |
+--------+-------------------------------+----+
| 8 | IPv4 neighbor address | N |
+--------+-------------------------------+----+
| 9-11 | Unassigned | |
+--------+-------------------------------+----+
| 12 | IPv6 Interface Address | N |
+--------+-------------------------------+----+
| 13 | IPv6 Neighbor Address | N |
+--------+-------------------------------+----+
| 14-255 | Unassigned | |
+--------+-------------------------------+----+
Table 11: IS-IS Sub-TLVs for Application-
Specific SRLG TLV
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9.2.12. MP-TLV for IS-IS Sub-Sub-TLVs for SRv6 SID Sub-TLVs
+=======+====================+====+
| Value | Name | MP |
+=======+====================+====+
| 0 | Reserved | |
+-------+--------------------+----+
| 1 | SRv6 SID Structure | N |
+-------+--------------------+----+
| 2-255 | Unassigned | |
+-------+--------------------+----+
Table 12: IS-IS Sub-Sub-TLVs
for SRv6 SID Sub-TLVs
9.2.13. MP-TLV for IS-IS Sub-Sub-TLVs for Flexible Algorithm Definition
Sub-TLV
+========+============================================+====+
| Value | Name | MP |
+========+============================================+====+
| 0 | Reserved | |
+--------+--------------------------------------------+----+
| 1 | Flexible Algorithm Exclude Admin Group | N |
+--------+--------------------------------------------+----+
| 2 | Flexible Algorithm Include-Any Admin Group | N |
+--------+--------------------------------------------+----+
| 3 | Flexible Algorithm Include-All Admin Group | N |
+--------+--------------------------------------------+----+
| 4 | Flexible Algorithm Definition Flags | N |
+--------+--------------------------------------------+----+
| 5 | Flexible Algorithm Exclude SRLG | N |
+--------+--------------------------------------------+----+
| 6 | IS-IS Exclude Minimum Bandwidth | N |
+--------+--------------------------------------------+----+
| 7 | IS-IS Exclude Maximum Delay | N |
+--------+--------------------------------------------+----+
| 8 | IS-IS Reference Bandwidth | N |
+--------+--------------------------------------------+----+
| 9 | IS-IS Threshold Metric | N |
+--------+--------------------------------------------+----+
| 10-255 | Unassigned | |
+--------+--------------------------------------------+----+
Table 13: IS-IS Sub-Sub-TLVs for Flexible Algorithm
Definition Sub-TLV
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9.2.14. MP-TLV for IS-IS Sub-Sub-TLVs for Flood Reflection Discovery
Sub-TLV
+=========+================================+====+
| Value | Name | MP |
+=========+================================+====+
| 0-160 | Unassigned | |
+---------+--------------------------------+----+
| 161 | Flood Reflection Discovery | N |
| | Tunnel Encapsulation Attribute | |
+---------+--------------------------------+----+
| 162-255 | Unassigned | |
+---------+--------------------------------+----+
Table 14: IS-IS Sub-Sub-TLVs for Flood
Reflection Discovery Sub-TLV
10. Security Considerations
This document creates no new security issues for IS-IS. Additional
instances of existing TLVs expose no new information.
Security concerns for IS-IS are addressed in [ISO10589], [RFC5304],
and [RFC5310].
11. Contributors
The following people gave a substantial contribution to the content
of this document and should be considered coauthors:
Chris Bowers
Email: cbowers107@gmail.com
12. Normative References
[ISO10589] ISO, "Intermediate system to Intermediate system routing
information exchange protocol for use in conjunction with
the Protocol for providing the Connectionless-mode Network
Service (ISO 8473)", November 2002, <ISO/IEC 10589:2002>.
[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>.
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[RFC5120] Przygienda, T., Shen, N., and N. Sheth, "M-ISIS: Multi
Topology (MT) Routing in Intermediate System to
Intermediate Systems (IS-ISs)", RFC 5120,
DOI 10.17487/RFC5120, February 2008,
<https://www.rfc-editor.org/info/rfc5120>.
[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>.
[RFC5305] Li, T. and H. Smit, "IS-IS Extensions for Traffic
Engineering", RFC 5305, DOI 10.17487/RFC5305, October
2008, <https://www.rfc-editor.org/info/rfc5305>.
[RFC5307] Kompella, K., Ed. and Y. Rekhter, Ed., "IS-IS Extensions
in Support of Generalized Multi-Protocol Label Switching
(GMPLS)", RFC 5307, DOI 10.17487/RFC5307, October 2008,
<https://www.rfc-editor.org/info/rfc5307>.
[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>.
[RFC6119] Harrison, J., Berger, J., and M. Bartlett, "IPv6 Traffic
Engineering in IS-IS", RFC 6119, DOI 10.17487/RFC6119,
February 2011, <https://www.rfc-editor.org/info/rfc6119>.
[RFC6213] Hopps, C. and L. Ginsberg, "IS-IS BFD-Enabled TLV",
RFC 6213, DOI 10.17487/RFC6213, April 2011,
<https://www.rfc-editor.org/info/rfc6213>.
[RFC7356] Ginsberg, L., Previdi, S., and Y. Yang, "IS-IS Flooding
Scope Link State PDUs (LSPs)", RFC 7356,
DOI 10.17487/RFC7356, September 2014,
<https://www.rfc-editor.org/info/rfc7356>.
[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>.
[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>.
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[RFC8202] Ginsberg, L., Previdi, S., and W. Henderickx, "IS-IS
Multi-Instance", RFC 8202, DOI 10.17487/RFC8202, June
2017, <https://www.rfc-editor.org/info/rfc8202>.
[RFC9479] Ginsberg, L., Psenak, P., Previdi, S., Henderickx, W., and
J. Drake, "IS-IS Application-Specific Link Attributes",
RFC 9479, DOI 10.17487/RFC9479, October 2023,
<https://www.rfc-editor.org/info/rfc9479>.
Authors' Addresses
Parag Kaneriya
Juniper Networks
Elnath-Exora Business Park Survey
Bangalore 560103
Karnataka
India
Email: pkaneria@juniper.net
Tony Li
Juniper Networks
1133 Innovation Way
Sunnyvale, California 94089
United States of America
Email: tony.li@tony.li
Antoni Przygienda
Juniper Networks
1133 Innovation Way
Sunnyvale, California 94089
United States of America
Email: prz@juniper.net
Shraddha Hegde
Juniper Networks
Elnath-Exora Business Park Survey
Bangalore 560103
Karnataka
India
Email: shraddha@juniper.net
Les Ginsberg
Cisco Systems
Email: ginsberg@cisco.com
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