TOC 
CCAMP Working GroupE. Bellagamba, Ed.
Internet-DraftL. Andersson, Ed.
Intended status: ExperimentalEricsson
Expires: April 1, 2010P. Skoldstrom
 Acreo AB
 September 28, 2009


RSVP-TE Extensions for MPLS-TP OAM Configuration
draft-bellagamba-ccamp-rsvp-te-mpls-tp-oam-ext-02

Status of this Memo

This Internet-Draft is submitted to IETF in full conformance with the provisions of BCP 78 and BCP 79.

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Abstract

This document defines a method for the configuration of MPLS-TP OAM functionalities through RSVP-TE Control Plane. The procedures presented are experimental and currently describe BFD configuration for CC and CV. Updated version of this document will possibly describe the configuration of the remaining MPLS-TP OAM functionalities.



Table of Contents

1.  Introduction
    1.1.  Contributing Authors
    1.2.  Requirements Language
    1.3.  Background
2.  Overview of BFD OAM operation
3.  RSVP-TE Extensions
    3.1.  Operation overview
    3.2.  OAM Configuration TLV
    3.3.  BFD CC OAM Configuration TLV
        3.3.1.  Local Discriminator sub-TLV
        3.3.2.  Suggested TX interval
    3.4.  BFD CC&CV OAM Configuration TLV
        3.4.1.  Trail Termination Source Identifier (TTSI) sub-TLV
            3.4.1.1.  LSP ME ID IPv4 Source/Destination Address Format sub-TLV
            3.4.1.2.  LSP ME ID IPv6 Source/Destination Address Format sub-TLV
            3.4.1.3.  FEC128PWv4 ME ID Format sub-TLV
            3.4.1.4.  FEC128PWv6 ME ID Format sub-TLV
            3.4.1.5.  ICC-based ME ID Format sub-TLV
4.  IANA Considerations
5.  BFD OAM configuration errors
6.  Security Considerations
7.  References
    7.1.  Normative References
    7.2.  Informative References
Appendix A.  Additional Stuff
§  Authors' Addresses




 TOC 

1.  Introduction

This document provides extensions to RSVP-TE in order to accommodate the MPLS-TP CC (Continuity Check) and CV (Connectivity Verification) MPLS-TP OAM functionalities. Further revisions of this document might describe RSVP-TE extensions for the other MPLS-TP OAM functionalities.

The procedures described are experimental and are intended to be possibly updated with other proposed OAM tools and BFD future extensions.

The document intent is both disseminating experimental results carried out within Ericsson Research and provide an initial input for further Control Plane extension in CCAMP IETF group.



 TOC 

1.1.  Contributing Authors

The editors gratefully acknowledge the precious contributions of (in alphabetical order) Annamaria Fulignoli, Andras Kern, David Jocha, David Sinicrope, Attila Takacs and Benoit Tremblay.



 TOC 

1.2.  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 (Bradner, S., “Key words for use in RFCs to Indicate Requirement Levels,” March 1997.) [RFC2119].



 TOC 

1.3.  Background

MPLS Transport Profile (MPLS-TP), describes a profile of MPLS that enables operational models typical in transport networks, while providing additional OAM, survivability and other maintenance functions not currently supported by MPLS.

RSVP-TE control plane [RFC3471] has been chosen to support the establishment of MPLS-TP LSPs.

[MPLS-TP-OAM-REQ] defines the requirements by which the OAM functionality of MPLS-TP should abide.

The MPLS-TP design team provided recommendations regarding the functionalities that should be covered by the existing toolsets and which extensions or new tools will be needed in order to provide full coverage of the OAM functionalities for MPLS-TP. A detailed overview of the adopted OAM tools will be documented in the next revision of [MPLS-TP OAM Analysis].

This document provides extensions to RSVP-TE in order to accommodate the MPLS-TP CC (Continuity Check) and CV (Connectivity Verification) MPLS-TP OAM functionalities. Further revisions of this document might describe RSVP-TE extensions for the other MPLS-TP OAM functionalities.

Bidirectional Forwarding Detection, as described in [BFD], defines a protocol that provides low-overhead, short-duration detection of failures in the path between two forwarding engines, including the interfaces, data link(s), and to the extent possible the forwarding engines themselves. BFD can be used to track the liveliness of MPLS-TP point-to-point and p2mp connections and detect data plane failures. This version of the draft is focused on unidirectional and bidirectional p2p connection.

BFD has been chosen to cover MPLS-TP CC functionality.

An extended version of BFD, as described in [BFD-CV], has been chosen to accomplish both MPLS-TP CC and CV.



 TOC 

2.  Overview of BFD OAM operation

BFD is a simple hello protocol that in many respects is similar to the detection components of well-known routing protocols. A pair of system transmits BFD packets periodically over each path between the two systems, and if a system stops receiving BFD packets for long enough, some component in that particular bidirectional path to the neighboring system is assumed to have failed. Systems may also negotiate to not send periodic BFD packets in order to reduce overhead.

A path is only declared to be operational when two-way communication has been established between systems, though this does not preclude the use of unidirectional links.

[BFD, sect. 3] states that a separate BFD session is created for each communications path and data protocol in use between two systems.

Each system estimates how quickly it can send and receive BFD packets in order to come to an agreement with its neighbor about how rapidly detection of failure will take place. These estimates can be modified in real time in order to adapt to unusual situations. This design also allows for fast systems on a shared medium with a slow system to be able to more rapidly detect failures between the fast systems while allowing the slow system to participate to the best of its ability.

The ability of each system to control the BFD packet transmission rate in both directions provides a mechanism for congestion control, particularly when BFD is used across multiple network hops.

As recommended in [BFD-CV], the BFD tool needs to be extended for the CV functionality by the addition of a unique identifier in order to meet the requirements. The document in [BFD-CV] specifies the BFD extension and behavior to meet the requirements for MPLS-TP proactive Continuity Check and Connectivity Verification functionality and the RDI functionality as defined in [MPLS-TP-OAM-REQ].



 TOC 

3.  RSVP-TE Extensions



 TOC 

3.1.  Operation overview

Below, extension to RSVP-TE for setting up BFD or BFD extended version are defined in order to configure MPLS-TP CC and CV OAM functionalities during the LSP setup.

The terms "ingress LER" and "egress LER" will not refer in this document to any direction in the forwarding plane, but only to the LER triggering the LSP setup (ingress LER) and the one triggering the response to it (egress LER).

During the LSP signaling, the Control Plane instance in the ingress and the egress LER announces the BFD OAM Configuration TLV (inside the LSP_ATTRIBUTES object carried by the Path and Resv message respectively), which includes the "Local Discriminator" sub-TLV. During the BFD session the ingress LER will use as "MyDiscriminator" the value announced in the "Local Discriminator"(Path message) and as "YourDiscriminator" the value received in the "Local Discriminator" (Resv message).

The system initiating the signaling MUST advertise the interval value at which it requires BFD control packets both in transmission and reception. If the receiving system can not support this value, a new value can be signaled back in the Resv message, with the constraint that the new value MUST be comprised between the Maximum and Minimum values indicated by the ingress. If the egress system can not support any value in the indicated range, it will reply with an error.

In the case BFD extended version should be configured, the ME ID unique parameter MUST be included along with the Discriminator and timing values as described in the following sections.



 TOC 

3.2.  OAM Configuration TLV

This TLV is specified in [OAM-CONF-FWK] and is used to select which OAM technology/method should be used for the LSP. In this document a new OAM Type: BFD OAM is defined.



OAM TypeDescription
0 Reserved
1 Ethernet OAM
2 BFD
3-256 Reserved

The receiving node when the BFD OAM Type is requested should look for the corresponding technology specific BFD OAM configuration TLV.

The receiving LER, when the BFD OAM Type is requested, should look for the corresponding technology specific BFD OAM configuration TLV. There are two types of allowed BFD OAM configuration TLV:

- "BFD CC OAM Configuration TLV" which MUST be used for configuring BFD for setting up the proactive MPLS-TP CC OAM tool (TLV type = 4)

- "BFD CC&CV OAM Configuration TLV" which MUST be used for configuring BFD for setting up the proactive MPLS-TP CC&CV OAM tool (TLV type = 5)

In case the receiving LER does not support the CC&CV functionality, an error "OAM Problem/Unsupported BFD functionality" must be generated when receiving the BFD CC&CV OAM Configuration TLV.



 TOC 

3.3.  BFD CC OAM Configuration TLV

The BFD CC OAM Configuration TLV (depicted below) is defined for BFD OAM specific configuration parameters. The BFD CC OAM Configuration TLV is carried as a sub-TLV of the "OAM Configuration TLV" in the LSP_ATTRIBUTES object both in Path and Resv messages.

This new TLV accommodates generic BFD OAM information and carries sub-TLVs.

    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 (4) (IANA)     |           Length              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Vers.|R|         Reserved (set to all 0s)                      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                           sub TLVs                            ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Type: indicates a new type, the "BFD CC OAM Configuration TLV" (4) (IANA to define).

Length: indicates the total length including sub-TLVs.

Version: identifies the BFD protocol version. If a node does not support a specific BFD version an error must be generated: “OAM Problem/Unsupported OAM Version ”

R Flag: Role Flag. If set, the receiving node is required to act with an Active Role as described in [BFD, sect. 6.1]. When the BFD OAM Configuration TLV is carried in the Resv message, the flag it not taken into consideration by the receiving node.

The BFD CC OAM Configuration TLV MUST include the following sub-TLVs during the Path signaling:

- "Local Discriminator" sub-TLV (described in paragraph 3.3.1)

- "Suggested TX interval" sub-TLV (described in paragraph 3.3.2)

The BFD CC OAM Configuration TLV MUST include the following sub-TLVs during the Resv signaling:

- "Local Discriminator" sub-TLV (described in paragraph 3.3.1)

- "Suggested TX interval" sub-TLV (described in paragraph 3.3.2) if a different timing value needs to be used.



 TOC 

3.3.1.  Local Discriminator sub-TLV

The Local Discriminator sub-TLV is depicted below.

    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 (1) (IANA)     |           Length              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |    		  Local Discriminator                      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Type: indicates a new type, the Local Discriminator sub TLV (1) (IANA to define).

Length: indicates the total length of the TLV including padding.

Local Discriminator: A unique, nonzero discriminator value generated by the transmitting system and referring to itself, used to demultiplex multiple BFD sessions between the same pair of systems. This Discriminator will be signaled both by the ingress LSR and the egress LSR in the Path and Resv message respectively.



 TOC 

3.3.2.  Suggested TX interval

The Suggested TX interval sub-TLV is depicted below.

       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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |  Req. TX int. Type (2) (IANA) |          Length = 24          |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |   	Acceptable Min. Asynchronous TX interval              |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |              Suggested Asynchronous TX interval               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |		Acceptable Max. Asynchronous TX interval	      |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |               Required Echo TX Interval                       |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |  Detect. Mult |           Reserved                            |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Type: indicates a new type, the Suggested TX interval sub TLV (3) (IANA to define).

Length: indicates the total length of the TLV including padding, it is set to 24 (octects).

Suggested Asynchronous TX interval: the interval, in microseconds, that the system initiating the signaling want to have when both transmitting and receiving BFD Control packets, less any jitter applied. The value zero is reserved. If the receiving system can not support this value, a new value can be signaled back in the Resv message, with the constraint that the new value will be not higher than "Acceptable Max. Asynchronous TX interval" and not lower than "Acceptable Min. Asynchronous TX interval".

Acceptable Min. Asynchronous TX interval: the maximum TX interval, in microseconds, that the system initiating the signaling can support. In case the receiving system sends back this TLV for proposing a different "Suggested Asynchronous TX interval", the "Acceptable Min. Asynchronous TX interval" will not be taken into consideration by the system which initiated the signaling.

Acceptable Max. Asynchronous TX interval: the minimum TX interval, in microseconds, that the system initiating the signaling can support. In case the receiving system sends back this TLV for proposing a different "Suggested Asynchronous TX interval", the "Acceptable Max. Asynchronous TX interval" will not be taken into consideration by the system which initiated the signaling.

Required Echo TX Interval: the minimum interval, in microseconds, between received BFD Echo packets that this system is capable of supporting, less any jitter applied by the sender as described in [BFD, sect. 6.8.9]. This value is also an indication for the receiving system of the minimum interval between transmitted BFD Echo packets. If this value is zero, the transmitting system does not support the receipt of BFD Echo packets. If the receiving system can not support this value an error MUST be generated "Unsupported BFD TX rate interval"



 TOC 

3.4.  BFD CC&CV OAM Configuration TLV

The BFD CC&CV OAM Configuration TLV (depicted below) is defined for BFD OAM specific configuration parameters. The BFD CC&CV OAM Configuration TLV is carried as a sub-TLV of the "OAM Configuration TLV" in the LSP_ATTRIBUTES object both in Path and Resv messages.

This new TLV accommodates generic BFD OAM information and carries sub-TLVs.

       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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |   BFD CC&CV  Type (5) (IANA)  |           Length              |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |Vers.|R|         Reserved (set to all 0s)                      |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                                                               |
      ~                           sub TLVs                            ~
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Type: indicates a new type, the BFD CC&CV OAM Configuration TLV (5) (IANA to define).

Length: indicates the TLV total length (in octects) including sub-TLVs.

Version: identifies the BFD protocol version. If a node does not support a specific BFD version an error must be generated: "OAM Problem/Unsupported OAM Version"

R Flag: Role Flag. If set, the receiving node is required to act with an Active Role as described in [BFD, sect. 6.1]. When the BFD OAM Configuration TLV is carried in the Resv message, the flag it not taken into consideration by the receiving node.

The BFD CC&CV OAM Configuration TLV MUST include the following sub-TLVs during the Path signaling:

The BFD CC&CV OAM Configuration TLV MUST include the following sub-TLVs during the Path signaling:

- "Local Discriminator" sub-TLV (described in paragraph 3.3.1)

- "Suggested TX interval" sub-TLV (described in paragraph 3.3.2)

- "Trail Termination Source Identifier" sub-TLV (described in paragraph 3.4.1)

The BFD CC OAM Configuration TLV MUST include the following sub-TLVs during the Resv signaling:

- "Local Discriminator" sub-TLV (described in paragraph 3.3.1)

- "Suggested TX interval" sub-TLV (described in paragraph 3.3.2) if a different timing value needs to be used.

The BFD CC&CV OAM Configuration TLV MUST include the following sub-TLVs during the Resv signaling:



 TOC 

3.4.1.  Trail Termination Source Identifier (TTSI) sub-TLV

The MPLS Generic Associated Channel specification (see[RFC5586, sect. 3]) describes the ACH TLV structure that can be used to provide additional context information to the G-ACh packet.

In this section it is showed how the TTSI sub-TLV in the BFD CC&CV OAM Configuration TLV can be used to configure the TLV Objects in the ACH TLV for providing the MEP Identifier information and the ME Identifier information as required by[MPLS-TP-OAM-FWK].

    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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |    TTSI Type (3) (IANA)       |           Length              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |       MEP ID value            |Reserved ( fixed to all ZEROs) !
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                  Unique ME ID sub-TLV                         ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Length: indicates the TLV total length (in octects) including sub-TLVs.

MEP ID value: 13-bit integer value field, identifying the transmitting MEP within the ME. The three MSBs of the first octet are not used and should be set to ZERO.

Unique ME ID: the value of the ME identifier. The ME Identifier Type transmitted and expected MUST be the same at both MEPs. Since different formats/semantics of ME ID Value can be chosen, the ME ID Value is encoded as a further TLV and the possible options are described in the next paragraphs.



 TOC 

3.4.1.1.  LSP ME ID IPv4 Source/Destination Address Format sub-TLV

This ME ID format MAY be used to identify an LME (as defined in [MPLS-TP-OAM-FWK]) where IPv4 addresses are used to identify the LERs terminating the LSP.

    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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | LSP ME ID IPv4 Type (1)(IANA) |         Length = 16           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                   IPv4 source address                         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                   IPv4 destination address                    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |         Tunnel Index          | Tunnel Instance Index         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

ME ID Type: indicates the specific format.

Length: indicates the sub-TLV total length and it is set to 16 (octets).

IPv4 source address: set to the IPv4 address of the LSP source port/node.

IPv4 destination address: set to the IPv4 address of the LSP destination port/node.

TunnelIndex: 2 octets field as defined in RFC 3812.

TunnelInstance Index: 2 octets field as defined in RFC 3812.

If the receiving LER does not support this ME ID format in an error must be generated: "OAM Problem/Unsupported ME ID Format".



 TOC 

3.4.1.2.  LSP ME ID IPv6 Source/Destination Address Format sub-TLV

This ME ID format MAY be used to identify an LME (as defined in [MPLS-TP-OAM-FWK]) where IPv6 addresses are used to identify the LERs terminating the LSP.

    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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | LSP ME ID IPv6 Type (2)(IANA) |           Length = 40         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                     IPv6 source address                       |
   ~                        (16 bytes)                             ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                     IPv6 destination address                  |
   ~                        (16 bytes)                             ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |         Tunnel Index          | TunnelInstance  Index         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

ME ID Type: indicates the specific format.

Length: indicates the sub-TLV total length and it is set to 40 (octets).

IPv6 source address: set to the IPv6 address of the LSP source port/node.

IPv6 destination address: set to the IPv6 address of the LSP destination port/node.

TunnelIndex: 2 octets field as defined in RFC 3812.

TunnelInstance Index: 2 octets field as defined in RFC 3812.

If the receiving LER does not support this ME ID format in an error must be generated: "OAM Problem/Unsupported ME ID Format".



 TOC 

3.4.1.3.  FEC128PWv4 ME ID Format sub-TLV

It contains a PW ID that terminates on a PE identified by an IPv4 address.

    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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |FEC128PWv4 ME ID Type (3)(IANA)|       Length = 16             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                          IPv4 Address                         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                          Group ID                             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                          PW ID                                |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

FEC128PWv4 Type: indicates the specific format.

Length: indicates the sub-TLV total length and it is set to 16 (octets).

IPv4 Address: IPv4 addresses are used to identify the T-PEs terminating the PW.

Group ID: indicates an arbitrary 32-bit value that represents a group of PWs that is used to create groups in the PW space, as specified in [RFC4447, sect. 5.2].

PW ID: a non-zero 32-bit pseudowire connection ID (PW ID) as specified in [RFC4447, sect. 5.2] that terminates on a PE identified by an IPv4 address.

If the receiving LER does not support this ME ID format in an error must be generated: "OAM Problem/Unsupported ME ID Format".



 TOC 

3.4.1.4.  FEC128PWv6 ME ID Format sub-TLV

It contains a PW ID that terminates on a PE identified by an IPv6 address.

    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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |FEC128PWv4 ME ID Type (4)(IANA)|       Length = 28             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   ~                          IPv6 Address                         ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                          Group ID                             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                          PW ID                                |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

FEC128PWv6 Type: indicates the specific format.

Length: indicates the sub-TLV total length and it is set to 28 (octets).

IPv6 Address: IPv6 addresses are used to identify the T-PEs terminating the PW.

Group ID: indicates an arbitrary 32-bit value that represents a group of PWs that is used to create groups in the PW space, as specified in [RFC4447, Sect. 5.2].

PW ID: a non-zero 32-bit pseudowire connection ID (PW ID) as specified in [RFC4447, sect. 5.2] that terminates on a PE identified by an IPv6 address.

If the receiving LER does not support this ME ID format in an error must be generated: "OAM Problem/Unsupported ME ID Format".



 TOC 

3.4.1.5.  ICC-based ME ID Format sub-TLV

This ME ID format MAY be used to identify SME, LME, LTCME, PME and PTCME(as defined in [MPLS-TP-OAM-FWK]) independently on LER/T-PE addressing schemes as well as of the FECs used to identify the PW.

    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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        ME ID Type             |       Length = 20             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   +                                                               +
   |                       MEG ID                                  |
   +                     (13 bytes)                                +
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |               |0 0 0 0 0 0 0 0|0 0 0 0 0 0 0 0|0 0 0 0 0 0 0 0|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

ME ID Type: it identifies the specific format, value = TBD.

Length: indicates the total length and it is set to 20.

MEG ID value: Refer to Annex A of ITU-T Recommendation Y.1731 for the format used for the MEG ID field with ICC-based format.

If the receiving LER does not support this ME ID format in an error must be generated: "OAM Problem/Unsupported ME ID Format".



 TOC 

4.  IANA Considerations

This document specifies the following new TLV types.

sub-TLVs types to be carried in the OAM Configuration TLV in LSP_ATTRIBUTES:

- "BFD CC OAM Configuration" sub-TLV type: 4

- "BFD CC&CV OAM Configuration" sub-TLV type (to be carried in the OAM Configuration TLV in LSP_ATTRIBUTES): 5

sub-TLV types to be carried in the BFD OAM Configuration sub-TLV:

- "Local Discriminator" sub-TLV type: 1

- "Suggested TX interval" sub-TLV type: 2

- "Trail Termination Source Identifier (TTSI)" sub-TLV type: 3

sub-TLV types to be carried in the TTSI sub-TLV:

- "LSP ME ID IPv4 Source/Destination Address Format" sub-TLV type: 1

- "LSP ME ID IPv6 Source/Destination Address Format" sub-TLV type: 2

- "FEC128PWv4 ME ID Format" sub-TLV type: 3

- "FEC128PWv6 ME ID Format" sub-TLV type: 4

- "ICC-based ME ID Format" sub-TLV type: 5



 TOC 

5.  BFD OAM configuration errors

In addition to error values specified in [OAM-CONF-FWK] and [ETH-OAM] this document defines the following values for the "OAM Problem" Error Code:

- "OAM Problem/Unsupported BFD functionality"

- "OAM Problem/Unsupported BFD TX rate interval"

- "OAM Problem/Unsupported ME ID Format"



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6.  Security Considerations

The signaling of OAM related parameters and the automatic establishment of OAM entities introduces additional security considerations to those discussed in [RFC3473]. In particular, a network element could be overloaded, if an attacker would request liveliness monitoring, with frequent periodic messages, for a high number of LSPs, targeting a single network element.

Security aspects will be covered in more detailed in subsequent versions of this document.



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7.  References



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7.1. Normative References

[BFD] Katz, D. and D. Ward, “Bidirectional Forwarding Detection,” 2009.
[BFD-CV] Fulignoli, A., Boutros, S., and M. Vigoreux, “MPLS-TP BFD for Proactive CC-CV and RDI,” 2009.
[MPLS-TP-OAM-FWK] Busi, I. and B. Niven-Jenkins, “MPLS-TP OAM Framework and Overview,” 2009.
[MPLS-TP-OAM-REQ] Vigoureux, M., Ward, D., and M. Betts, “Requirements for OAM in MPLS Transport Networks,” 2009.
[OAM-CONF-FWK] Takacs, A., Fedyk, D., and J. van He, “OAM Configuration Framework for GMPLS RSVP-TE,” 2009.
[RFC2119] Bradner, S., “Key words for use in RFCs to Indicate Requirement Levels,” BCP 14, RFC 2119, March 1997 (TXT, HTML, XML).
[RFC3471] Berger, L., “Generalized Multi-Protocol Label Switching (GMPLS) Signaling Functional Description,” RFC 3471, January 2003 (TXT).
[RFC4447] Martini, L., Rosen, E., El-Aawar, N., Smith, T., and G. Heron, “Pseudowire Setup and Maintenance Using the Label Distribution Protocol (LDP),” RFC 4447, April 2006 (TXT).
[RFC5586] Bocci, M., Vigoureux, M., and S. Bryant, “MPLS Generic Associated Channel,” RFC 5586, June 2009 (TXT).


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7.2. Informative References

[ETH-OAM] Takacs, A., Gero, B., Fedyk, D., Mohan, D., and D. Long, “GMPLS RSVP-TE Extensions for Ethernet OAM,” 2009.
[LSP Ping] Kompella, K. and G. Swallow, “Detecting Multi-Protocol Label Switched (MPLS) Data Plane Failures,” 2006.
[MPLS-TP OAM Analysis] Sprecher, N., Nadeau, T., van Helvoort, H., and Weingarten, “MPLS-TP OAM Analysis,” 2006.


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Appendix A.  Additional Stuff

This becomes an Appendix.



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Authors' Addresses

  Elisa Bellagamba (editor)
  Ericsson
  Farogatan 6
  Kista, 164 40
  Sweden
Phone:  +46 761440785
Email:  elisa.bellagamba@ericsson.com
  
  Loa Andersson (editor)
  Ericsson
  Farogatan 6
  Kista, 164 40
  Sweden
Phone: 
Email:  loa.andersson@ericsson.com
  
  Pontus Skoldstrom
  Acreo AB
  Electrum 236
  Kista, 164 40
  Sweden
Phone:  +46 8 6327731
Email:  pontus.skoldstrom@acreo.se