Control Protocol Extensions for the Setup of Time-Division Multiplexing (TDM) Pseudowires in MPLS Networks
RFC 5287
Network Working Group A. Vainshtein
Request for Comments: 5287 ECI Telecom
Category: Standards Track Y(J). Stein
RAD Data Communications
August 2008
Control Protocol Extensions for the Setup of
Time-Division Multiplexing (TDM) Pseudowires in MPLS Networks
Status of This Memo
This document specifies an Internet standards track protocol for the
Internet community, and requests discussion and suggestions for
improvements. Please refer to the current edition of the "Internet
Official Protocol Standards" (STD 1) for the standardization state
and status of this protocol. Distribution of this memo is unlimited.
Abstract
This document defines extension to the Pseudowire Emulation Edge-to-
Edge (PWE3) control protocol RFC 4447 and PWE3 IANA allocations RFC
4446 required for the setup of Time-Division Multiplexing (TDM)
pseudowires in MPLS networks.
Table of Contents
1. Introduction ....................................................2
2. PW FEC for Setup of TDM PWs .....................................2
3. Interface Parameters for TDM PWs ................................4
3.1. Overview ...................................................4
3.2. CEP/TDM Payload Bytes ......................................5
3.3. CEP/TDM Bit-Rate (0x07) ....................................5
3.4. Number of TDMoIP AAL1 Cells per Packet .....................6
3.5. TDMoIP AAL1 Mode ...........................................7
3.6. TDMoIP AAL2 Options ........................................7
3.7. Fragmentation Indicator ....................................8
3.8. TDM Options ................................................8
4. Extending CESoPSN Basic NxDS0 Services with CE
Application Signaling ..........................................11
5. LDP Status Codes ...............................................12
6. Using the PW Status TLV ........................................13
7. IANA Considerations ............................................13
8. Security Considerations ........................................14
9. Acknowledgements ...............................................14
10. References ....................................................14
10.1. Normative References .....................................14
10.2. Informative References ...................................14
Vainshtein & Stein Standards Track [Page 1]
RFC 5287 Control Protocol Extensions for TDM Pseudowires August 2008
1. Introduction
This document defines an extension to the PWE3 control protocol
[RFC4447] and PWE3 IANA allocations [RFC4446] required for the setup
of TDM pseudowires in MPLS networks.
Structure-agnostic TDM pseudowires have been specified in [RFC4553],
and structure-aware ones have been specified in [RFC5086] and
[RFC5087].
[RFC4447] defines extensions to the Label Distribution Protocol (LDP)
[RFC5036] that are required to exchange PW labels for PWs emulating
various Layer 2 services (Ethernet, Frame Relay (FR), Asynchronous
Transfer Mode (ATM), High-Level Data Link Control (HDLC), etc.). The
setup of TDM PWs requires both interpretation of the existing
information elements of these extensions and exchange of additional
information.
The setup of TDM PWs using L2TPv3 will be defined in a separate
document.
The status of attachment circuits of TDM PWs can be exchanged between
the terminating Provider Edges (PEs) using the PW Status mechanism
defined in [RFC4447] without any changes. However, usage of this
mechanism is NOT RECOMMENDED for TDM PWs since the indication of the
status of the TDM attachment circuits is carried in-band in the data
plane.
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 [RFC2119].
2. PW FEC for Setup of TDM PWs
[RFC4447] uses the LDP Label Mapping message [RFC5036] for
advertising the FEC-to-PW Label binding, and defines two types of PW
Forwarding Equivalence Classes (FECs) that can be used for this
purpose:
1. PWId FEC (FEC 128). This FEC contains:
a) PW type
b) Control bit (indicates presence of the control word)
c) Group ID
d) PW ID
Vainshtein & Stein Standards Track [Page 2]
RFC 5287 Control Protocol Extensions for TDM Pseudowires August 2008
e) Interface parameters Sub-TLV
2. Generalized PW FEC (FEC 129). This FEC contains only:
a) PW type
b) Control bit
c) Attachment Group Identifier (AGI), Source Attachment Individual
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