Technical Summary
This document describes transport of TDM bit-streams over the Layer Two
Tunneling Protocol Version 3 (L2TPv3). It describes extensions of L2TPv3
for the setup and maintenance of structure-agnostic and structure-aware
TDM Pseudowires, to transport TDM bit-streams over an IP network.
Working Group Summary
There is consensus in the WG to publish this document.
Document Quality
The l2tpext WG has reviewed this document. All concerns raised during
review and last call have been addressed.
Yaakov Stein performed a very detailed review during WGLC, with the
conclusion that "this ID looks ready for publication" at
<http://www.ietf.org/mail-archive/web/l2tpext/current/msg01182.html>.
This document defines an application of L2TPv3 to transport another type
of traffic, and is consistent with corresponding PWE3 documents.
Carlos Pignataro is the WG shepherd for this document.
RFC Editor Note
Section 4., paragraph 12:
EXPLANATION: Adding Error code of zero.
OLD:
1. EC-TBD-1 - Bit Rate values disagree.
2. EC-TBD-2 - Different trunk types in the case of trunk-
specific CESoPSN with CAS
3. EC-TBD-3 - Requested payload size too big or too small.
4. EC-TBD-4 - RTP header cannot be generated.
5. EC-TBD-5 - Requested timestamp clock frequency cannot be
generated
NEW:
| 0 - No TDM PW parameter error
1. EC-TBD-1 - Bit Rate values disagree.
2. EC-TBD-2 - Different trunk types in the case of trunk-
specific CESoPSN with CAS
3. EC-TBD-3 - Requested payload size too big or too small.
4. EC-TBD-4 - RTP header cannot be generated.
5. EC-TBD-5 - Requested timestamp clock frequency cannot be
generated
Section 2.1, paragraph 3:
EXPLANATION: Clarification
OLD:
The Bit Rate field contains the value that represents the bit rate of
the local AC in the units of 64 Kbit/s encoded as an unsigned 16-bit
integer. Its usage for all types of TDM PWs employs the following
semantics:
| 1) Only the following values MUST be specified for structure-
| agnostic emulation (see [RFC4553]):
a) Structure-agnostic E1 emulation - 32
b) Structure-agnostic T1 emulation:
i) MUST be set to 24 for the basic mode
ii) MUST be set to 25 for the "Octet-aligned T1"
mode
c) Structure-agnostic E3 emulation - 535
d) Structure-agnostic T3 emulation - 699
2) For CESoPSN PWs this parameter MUST be set to the number of
DS0 channels in the corresponding attachment circuit.
NEW:
The Bit Rate field contains the value that represents the bit rate of
the local AC in the units of 64 Kbit/s encoded as an unsigned 16-bit
integer. Its usage for all types of TDM PWs employs the following
semantics:
| 1) For structure-agnostic emulation, this parameter MUST be set to
| one of the following values (see [RFC4553]):
a) Structure-agnostic E1 emulation - 32
b) Structure-agnostic T1 emulation:
i) MUST be set to 24 for the basic mode
ii) MUST be set to 25 for the "Octet-aligned T1"
mode
c) Structure-agnostic E3 emulation - 535
d) Structure-agnostic T3 emulation - 699
2) For CESoPSN PWs this parameter MUST be set to the number of
DS0 channels in the corresponding attachment circuit.