wdiff rfc8408.original rfc8408.txt

PCE Working Group
Internet Engineering Task Force (IETF) S. Sivabalan
Internet-Draft
Request for Comments: 8408 Cisco Systems, Inc.
Intended status:
Category: Standards Track J. Tantsura
Expires: November 5, 2018
ISSN: 2070-1721 Nuage Networks
I. Minei
Google, Inc.
R. Varga
Pantheon Technologies SRO
J. Hardwick
Metaswitch Networks
May 4,
June 2018

Conveying path setup type Path Setup Type in PCEP messages
draft-ietf-pce-lsp-setup-type-10 PCE Communication Protocol (PCEP) Messages

Abstract

A Path Computation Element (PCE) can compute Traffic Engineering (TE)
paths through a network that network; these paths are subject to various
constraints. Currently, TE paths are Label Switched Paths (LSPs) which
that are set up using the RSVP-TE signaling protocol. However, other
TE path setup methods are possible within the PCE architecture. This
document proposes an extension to the PCE communication protocol Communication Protocol
(PCEP) to allow support for different path setup methods over a given
PCEP session.

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 an Internet Standards Track document.

This document is a product of the Internet Engineering Task Force
(IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list It represents the consensus of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.

Internet-Drafts are draft documents valid the IETF community. It has
received public review and has been approved for a maximum publication by the
Internet Engineering Steering Group (IESG). Further information on
Internet Standards is available in Section 2 of RFC 7841.

Information about the current status of six months this document, any errata,
and how to provide feedback on it may be updated, replaced, or obsoleted by other documents obtained 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 November 5, 2018.
https://www.rfc-editor.org/info/rfc8408.

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Provisions Relating to IETF Documents
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Table of Contents

1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Requirements Language . . . . . . . . . . . . . . . . . . 3
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4 3
3. Path Setup Type Capability TLV . . . . . . . . . . . . . . . 4
4. Path Setup Type TLV . . . . . . . . . . . . . . . . . . . . . 6 5
5. Operation . . . . . . . . . . . . . . . . . . . . . . . . . . 6
6. Manageability Considerations . . . . . . . . . . . . . . . . 8 7
7. Security Considerations . . . . . . . . . . . . . . . . . . . 8
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 9
8.1. Additions to PCEP TLV Type Indicators . . . . . . . . . . . Registry . . . . . 9
8.2. New PCEP Path Setup Type Types Registry . . . . . . . . . . . . . . 9
8.3. PCEP-Error Additions to PCEP-ERROR Object Error Types and Values
Registry . . . . . . . . . . . . . . . . . . . . 10
9. Contributors . . . . 9
9. References . . . . . . . . . . . . . . . . . . . . 10
10. Acknowledgements . . . . . 9
9.1. Normative References . . . . . . . . . . . . . . . . . 10
11. . 9
9.2. Informative References . . . . . . . . . . . . . . . . . 10
Acknowledgements . . . . . . . . 10
11.1. Normative References . . . . . . . . . . . . . . . . 11
Contributors . . . . . . . . . 10
11.2. Informative References . . . . . . . . . . . . . . . . . 11
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 11

1. Introduction

[RFC5440] describes the Path Computation Element communication PCE Communication Protocol (PCEP) for
communication between a Path Computation Client (PCC) and a Path
Computation Element (PCE), (PCE) or between a PCE and a PCE. A PCC requests
requests, from a PCE, a path subject to various constraints and
optimization criteria from a PCE. criteria. The PCE responds to the PCC with a hop-by-hop
path in an Explicit Route Object (ERO). The PCC uses the ERO to set
up the path in the network.

[RFC8231] specifies extensions to PCEP that allow a PCC to delegate
its LSPs to a PCE. The PCE can then update the state of LSPs
delegated to it. In particular, the PCE may modify the path of an
LSP by sending a new ERO. The PCC uses this ERO to re-route reroute the LSP
in a make-before-break fashion. [RFC8281] specifies a mechanism
allowing that
allows a PCE to dynamically instantiate an LSP on a PCC by sending
the ERO and the characteristics of the LSP. The PCC creates the LSP
using the ERO and other attributes sent by the PCE.

So far, PCEP and its extensions have assumed that the TE paths are
label switched and are established via the RSVP-TE signaling
protocol. However, other methods of LSP setup are possible in the
PCE architecture (see [RFC4655] and [RFC4657]). This document
generalizes PCEP to allow other LSP setup methods to be used. It
defines two new TLVs and specifies the base procedures to facilitate
this, as follows.
this:

o The PATH-SETUP-TYPE-CAPABILITY TLV, which TLV allows a PCEP speaker to
announce which LSP setup methods it supports when the PCEP session
is established.

o The PATH-SETUP-TYPE TLV, which TLV allows a PCEP speaker to specify which
setup method should be used for a given LSP. When multiple path
setup types are deployed in a network, a given PCEP session may
have to simultaneously support more than one path setup type. A
PCEP speaker uses the PATH-SETUP-TYPE TLV to explicitly indicate
the intended path setup type in the appropriate PCEP messages,
unless the path setup type is RSVP-TE (which is assumed to be the
path setup type if no other setup type is indicated). This is so
that both the PCC and the PCE can take the necessary steps to set
up the path.

This document defines a path setup type code for RSVP-TE. When a new
path setup type (other than RSVP-TE) is introduced for setting up a
path, a path setup type code and, optionally, a sub-TLV pertaining to
the new path setup type will be defined by the document that
specifies the new path setup type.

1.1. 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.

2. Terminology

The following terminologies are terminology is used in this document:

ERO: Explicit Route Object.

LSR: Label Switching Router. Object

PCC: Path Computation Client. Client

PCE: Path Computation Element.

PCEP: Path Computation Element Protocol.

PCEP: PCE Communication Protocol
PST: Path Setup Type. Type

TLV: Type, Length, and Value. Value

3. Path Setup Type Capability TLV

A PCEP speaker indicates which PSTs it supports during the PCEP
initialization phase, as follows. phase using the following process. When the PCEP
session is created, it sends an Open message with an OPEN object
containing the PATH-
SETUP-TYPE-CAPABILITY PATH-SETUP-TYPE-CAPABILITY TLV. The format of this
TLV is as follows.

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 (TBD1) (34) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reserved | Num of PSTs |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| PST#1 | ... | PST#N | Padding |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
// Optional sub-TLVs (variable) //
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Figure 1: PATH-SETUP-TYPE-CAPABILITY TLV

The TLV type Type is TBD1 (to be assigned by IANA). 34. Its reserved Reserved field MUST be set to zero by the
sender and MUST be ignored by the receiver. The other fields in the
TLV are as follows.

Length: The total length in bytes of the remainder of the TLV, that
is, excluding the Type and Length fields.

Number

Num of PSTs: The number of PSTs in the following list, excluding
padding.

List of PSTs: A list of the PSTs that the PCEP speaker supports.
Each PST is a single byte in length. Duplicate entries in this
list MUST be ignored. The PCEP speaker MUST pad the list with
zeros so that it is a muliple multiple of four bytes in length. This
document defines the following PST value:

* PST = 0: Path is setup set up using the RSVP-TE signaling protocol. protocol

Optional sub-TLVs: A list of sub-TLVs associated with the supported
PSTs. Each PST has zero or one sub-TLVs associated with it, and
each sub-TLV is associated with exactly one PST. Each sub-TLV
MUST obey the rules for TLV formatting defined in ([RFC5440]). [RFC5440]. That
is, each sub-TLV is padded to a four byte four-byte alignment, and the
length
Length field of each sub-TLV does not include the padding bytes.
This document does not define any sub-TLVs; an example sub-TLV can
be found in [I-D.ietf-pce-segment-routing]. [PCEP-EXTENSIONS].

A PCEP speaker MUST check that this TLV is correctly formatted, as
follows.

o If there are no sub-TLVs, then the TLV length Length field MUST be equal
to four bytes plus the size of the PST list, excluding any padding
bytes.

o If there are sub-TLVs sub-TLVs, then the TLV Length field MUST be equal to
four bytes plus the size of the PST list (rounded up to the
nearest multiple of four) plus the size of the appended sub-TLVs sub-TLVs,
excluding any padding bytes in the final sub-TLV.

o The Number Num of PSTs field MUST be greater than zero.

If a PCEP speaker receives a PATH-SETUP-TYPE-CAPABILITY TLV which that
violates these rules, then the PCEP speaker MUST send a PCErr message
with Error-Type = 10 (Reception of an invalid object) and Error-Value Error-value
= 11 (Malformed object) and MUST close the PCEP session. The PCEP
speaker MAY include the malformed OPEN object in the PCErr message as
well.

If a PCEP speaker receives an OPEN object with more than one PATH-
SETUP-TYPE-CAPABILITY TLV TLV, then it MUST ignore all but the first
instance of this TLV.

The absence of the PATH-SETUP-TYPE-CAPABILITY TLV from the OPEN
object is equivalent to a PATH-SETUP-TYPE-CAPABILITY TLV containing a
single PST value of 0 (RSVP-TE (Path is set up using the RSVP-TE signaling
protocol) and no sub-TLVs. A PCEP speaker MAY omit the PATH-SETUP-TYPE-CAPABILITY PATH-SETUP-
TYPE-CAPABILITY TLV if the only PST it supports is RSVP-TE. If a
PCEP speaker supports other PSTs besides RSVP-TE, then it SHOULD
include the PATH-SETUP-TYPE-
CAPABILITY PATH-SETUP-TYPE-CAPABILITY TLV in its OPEN object.

If a PCEP speaker does not recognize the PATH-SETUP-TYPE-CAPABILITY
TLV, it will ignore the TLV in accordance with [RFC5440].

4. Path Setup Type TLV

When a PCEP session is used to set up TE paths using different
methods, the corresponding PCE and PCC must be aware of the path
setup method used. That means, This means that a PCE must be able to specify
paths in the correct format format, and a PCC must be able to take control control-
plane and forwarding plane forwarding-plane actions appropriate to the PST.

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 (28) | Length (4) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reserved | PST |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Figure 2: PATH-SETUP-TYPE TLV

The PATH-SETUP-TYPE TLV is an optional TLV associated with the RP
([RFC5440])
Request Parameters (RP) [RFC5440] and the SRP ([RFC8231]) Stateful PCE Request
Parameters (SRP) [RFC8231] objects. Its format is shown in
the above figure. Figure 2.
The TLV type is 28. Its reserved Reserved field MUST be set to zero. The one byte value
one-byte PST field contains the PST as defined for the
PATH-SETUP-TYPE-CAPABILITY PATH-SETUP-
TYPE-CAPABILITY TLV.

The absence of the PATH-SETUP-TYPE TLV is equivalent to a PATH-SETUP-
TYPE TLV with a PST value of 0 (RSVP-TE). (Path is set up using the RSVP-TE
signaling protocol). A PCEP speaker MAY omit the TLV if the PST is
RSVP-TE. If the RP or SRP object contains more than one PATH-SETUP-TYPE PATH-SETUP-
TYPE TLV, only the first TLV MUST be processed processed, and the rest MUST be
ignored.

If a PCEP speaker does not recognize the PATH-SETUP-TYPE TLV, it will
ignore the TLV in accordance with [RFC5440], [RFC5440] and will use RSVP-TE to set up
the path.

5. Operation

During the PCEP initialization phase, if a PCEP speaker receives a
PATH-SETUP-TYPE-CAPABILITY TLV from its peer, it MUST assume that the
peer supports only the PSTs listed in the TLV. If the PCEP speaker
and its peer have no PSTs in common, then the PCEP speaker MUST send
a PCErr message with Error-Type = 21 (Invalid traffic engineering
path setup type) and Error-Value Error-value = 2 (Mismatched path setup type) and
close the PCEP session.

If the peer has sent no PATH-SETUP-TYPE-CAPABILITY TLV, then the PCEP
speaker MUST infer that the peer supports path setup using at least
RSVP-TE. The PCEP speaker MAY also infer that the peer supports
other path setup types, but the means of inference are outside the
scope of this document.

When a PCC sends a PCReq message to a PCE ([RFC5440]), [RFC5440], it MUST include
the PATH-SETUP-TYPE TLV in the RP object, unless the intended PST is RSVP-TE, in
RSVP-TE (in which case it MAY omit the PATH-SETUP-TYPE TLV. TLV). If the
PCE is capable of expressing the path in a format appropriate to the
intended PST, it MUST use the appropriate ERO format in the PCRep
message.

When a PCE sends a PCRep message to a PCC ([RFC5440]), [RFC5440], it MUST include
the PATH-SETUP-TYPE TLV in the RP object, unless the PST is
RSVP-TE, in RSVP-TE
(in which case it MAY omit the PATH-SETUP-TYPE TLV. TLV). If the PCE does
not support the intended PST, it MUST send a PCErr message with
Error-Type = 21 (Invalid traffic engineering path setup type) and Error-Value
Error-value = 1 (Unsupported path setup type) and close the PCEP
session. If the PSTs corresponding to the PCReq and PCRep messages
do not match, the PCC MUST send a PCErr message with Error-Type = 21
(Invalid traffic engineering path setup type) and Error-Value Error-value = 2
(Mismatched path setup type) and close the PCEP session.

When a stateful PCE sends a PCUpd message ([RFC8231]) [RFC8231] or a PCInitiate
message ([RFC8281]) [RFC8281] to a PCC, it MUST include the PATH-SETUP-TYPE TLV
in the SRP object, unless the intended PST is RSVP-TE, in RSVP-TE (in which case
it MAY omit the PATH-SETUP-TYPE TLV. TLV). If the PCC does not support
the PST associated with the PCUpd or PCInitiate message, it MUST send
a PCErr message with Error-Type = 21 (Invalid traffic engineering
path setup type) and Error-Value Error-value = 1 (Unsupported path setup type)
and close the PCEP session.

When a PCC sends a PCRpt message to a stateful PCE ([RFC8231]), [RFC8231], it MUST
include the PATH-SETUP-TYPE TLV in the SRP object, unless the PST is RSVP-TE, in
RSVP-TE (in which case it MAY omit the PATH-SETUP-TYPE TLV. TLV). The PCC
MUST include the SRP object in the PCRpt message if the PST is not
RSVP-TE, even when the SRP-ID-number is the reserved value of
0x00000000. If the PCRpt message is triggered by a PCUpd or
PCInitiate message, then the PST that the PCC indicates in the PCRpt
message MUST match the PST that the stateful PCE intended in the
PCUpd or
PCInitiate. PCInitiate message. If it does not, not match, then the PCE MUST
send a PCErr message with Error-Type = 21 (Invalid traffic
engineering path setup type) and Error-Value Error-value = 2 (Mismatched path
setup type) and close the PCEP session.

6. Manageability Considerations

This document generalises generalizes PCEP to allow path setup methods other than
RSVP-TE to be used by the network (but does not define any new path
setup types, types besides RSVP-TE). It is possible that, in a given
network, multiple path setup methods will be used. It is also
possible that not all devices will support the same set of path setup
methods. Managing networks that combine multiple path setup methods
may therefore raise some challenges from a configuration and
observability point of view.

Each document that defines a new Path Setup Type path setup type in the "PCEP Path
Setup
Type Registry Types" registry (Section 8.2) must include a manageability Manageability
Considerations section. The manageability Manageability Considerations section
must explain how operators can manage PCEP with the new path setup
type. It must address the following questions, which are generally
applicable when working with multiple path setup types in PCEP.

o What are the criteria for when devices will use the new path setup
type in PCEP, and how can the operator control this?

o How can the network be migrated to the new path setup type, and
are there any backwards compatibility backwards-compatibility issues that operators need
to be aware of?

o Are paths set up using the new path setup type intended to coexist
with other paths over the long term and, term, and if so, how is this
situation managed with PCEP?

o How can operators verify the correct operation of PCEP in the
network with respect to the new path setup type? Which fault
conditions must be reported to the operators?

o Are there any existing management interfaces (such as YANG models)
that must be extended to model the operation of PCEP in the
network with respect to the new path setup type?

See [RFC5706] for further guidance on how to write manageability Manageability
Considerations sections in standards-track Standards Track documents.

7. Security Considerations

The security considerations described in [RFC5440] and [RFC8281] are
applicable to this specification. No additional security measure is
required.

Note that, that if the security mechanisms of [RFC5440] and [RFC8281] are
not used, then the protocol described by in this draft document could be
attacked in the following new way. An attacker, using a TCP man-in-the-middle man-in-
the-middle attack, could inject error messages into the PCEP session
when a particular PST is (or is not) used. By doing so, the attacker Doing this could
potentially force the use of a specific PST, which may allow them the
attacker to subsequently attack a weakness in that PST.

8. IANA Considerations

8.1. Additions to PCEP TLV Type Indicators Registry

IANA is requested to confirm the early allocation of has allocated the following code point points in the PCEP "PCEP TLV Type Indicators
Indicators" registry.

Value Description Reference
----- -------------------------- ---------
28 PATH-SETUP-TYPE This document

IANA is requested to allocate a new code point for the following TLV
in the PCEP TLV Type Indicators registry.

Value Description Reference

TBD1 RFC 8408
34 PATH-SETUP-TYPE-CAPABILITY This document

Note to IANA: The above TLV type was not part of the early code point
allocation that was done for this draft. It was added to the draft
after the early code point allocation had taken place. Please assign
a code point from the indicated registry and replace each instance of
"TBD1" in this document with the allocated code point. RFC 8408

8.2. New PCEP Path Setup Type Types Registry

IANA is requested to create has created a new sub-registry within the "Path Computation
Element Protocol (PCEP) Numbers" registry called "PCEP Path Setup
Types". The allocation policy for this new registry
should be by is IETF Review. The Review
[RFC8126]. This new registry should contain contains the following value:

Value Description Reference
----- -------------------------- ---------
0 Path is setup set up using the RSVP- This document
TE RFC 8408
RSVP-TE signaling protocol. protocol

8.3. PCEP-Error Additions to PCEP-ERROR Object Error Types and Values Registry

IANA is requested to confirm the early allocation of has allocated the following
code-points code points in the PCEP-ERROR "PCEP-ERROR
Object Error Types and Values Values" registry.

Error-Type Meaning Reference
---------- ------------------------------------------- ---------
10 Reception of an invalid object

Error-value=11: RFC 5440

Error-value = 11: Malformed object

Error-Type Meaning RFC 8408

21 Invalid traffic engineering path setup type

Error-value=0: RFC 8408

Error-value = 0: Unassigned
Error-value=1: RFC 8408
Error-value = 1: Unsupported path setup type
Error-value=2: RFC 8408
Error-value = 2: Mismatched path setup type

Note to IANA: the early allocation for Error-Type=10, Error-value=11
was originally done by draft-ietf-pce-segment-routing. However, we
have since moved its definition into this document. Therefore,
please update the reference for this Error-value in the indicated
registry to point to RFC.ietf-pce-lsp-setup-type. RFC 8408

9. Contributors

The following people contributed to this document:

- Jan Medved
- Edward Crabbe

10. Acknowledgements

We like to thank Marek Zavodsky for valuable comments.

11. References

11.1.

9.1. Normative References
[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>.

[RFC5440] Vasseur, JP., Ed. and JL. Le Roux, Ed., "Path Computation
Element (PCE) Communication Protocol (PCEP)", RFC 5440,
DOI 10.17487/RFC5440, March 2009,
<https://www.rfc-editor.org/info/rfc5440>.

[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>.

[RFC8231] Crabbe, E., Minei, I., Medved, J., and R. Varga, "Path
Computation Element Communication Protocol (PCEP)
Extensions for Stateful PCE", RFC 8231,
DOI 10.17487/RFC8231, September 2017,
<https://www.rfc-editor.org/info/rfc8231>.

[RFC8281] Crabbe, E., Minei, I., Sivabalan, S., and R. Varga, "Path
Computation Element Communication Protocol (PCEP)
Extensions for PCE-Initiated LSP Setup in a Stateful PCE
Model", RFC 8281, DOI 10.17487/RFC8281, December 2017,
<https://www.rfc-editor.org/info/rfc8281>.

11.2.

9.2. Informative References

[I-D.ietf-pce-segment-routing]

[PCEP-EXTENSIONS]
Sivabalan, S., Filsfils, C., Tantsura, J., Henderickx, W.,
and J. Hardwick, "PCEP Extensions for Segment Routing",
draft-ietf-pce-segment-routing-11 (work
Work in progress), Progress, draft-ietf-pce-segment-routing-11,
November 2017.

[RFC4655] Farrel, A., Vasseur, J., and J. Ash, "A Path Computation
Element (PCE)-Based Architecture", RFC 4655,
DOI 10.17487/RFC4655, August 2006,
<https://www.rfc-editor.org/info/rfc4655>.

[RFC4657] Ash, J., Ed. and J. Le Roux, Ed., "Path Computation
Element (PCE) Communication Protocol Generic
Requirements", RFC 4657, DOI 10.17487/RFC4657, September
2006, <https://www.rfc-editor.org/info/rfc4657>.

[RFC5706] Harrington, D., "Guidelines for Considering Operations and
Management of New Protocols and Protocol Extensions",
RFC 5706, DOI 10.17487/RFC5706, November 2009,
<https://www.rfc-editor.org/info/rfc5706>.

[RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for
Writing an IANA Considerations Section in RFCs", BCP 26,
RFC 8126, DOI 10.17487/RFC8126, June 2017,
<https://www.rfc-editor.org/info/rfc8126>.

Acknowledgements

We would like to thank Marek Zavodsky for valuable comments.

Contributors

The following people contributed to this document:

- Jan Medved
- Edward Crabbe

Authors' Addresses

Siva Sivabalan
Cisco Systems, Inc.
2000 Innovation Drive
Kanata, Ontario K2K 3E8
Canada

Email: msiva@cisco.com

Jeff Tantsura
Nuage Networks
755 Ravendale Drive
Mountain View, CA 94043
USA
United States of America

Email: jefftant.ietf@gmail.com

Ina Minei
Google, Inc.
1600 Amphitheatre Parkway
Mountain View, CA 94043
USA
United States of America

Email: inaminei@google.com
Robert Varga
Pantheon Technologies SRO
Mlynske Nivy 56
Bratislava, 821 05
Slovakia

Email: nite@hq.sk

Jon Hardwick
Metaswitch Networks
100 Church Street
Enfield, Middlesex
UK
United Kingdom

Email: jonathan.hardwick@metaswitch.com