Network Working Group Luca Martini (Editor)
Internet Draft Cisco Systems, Inc.
Expiration Date: August 2006 Claude Kawa (Editor)
Andrew Malis (Editor) Oz Communications
Tellabs
February 2006
Encapsulation Methods for Transport of Frame Relay Over MPLS Networks
draft-ietf-pwe3-frame-relay-07.txt
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Abstract
A frame relay pseudo wire is a mechanism that exists between a
provider's edge network nodes and support as faithfully as possible
frame relay services over MPLS packet switched network (PSN). This
document describes the detailed encapsulation necessary to transport
frame relay packets over an MPLS network.
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Table of Contents
1 Specification of Requirements .......................... 3
2 Co-authors ............................................. 3
3 Acronyms and Abbreviations ............................. 4
4 Introduction ........................................... 4
5 Applicability Statement ................................ 6
6 General encapsulation method ........................... 6
7 Frame Relay over MPLS PSN for the One-to-One Mode ...... 7
7.1 MPLS PSN Tunnel and PW ................................. 7
7.2 Packet Format over MPLS PSN ............................ 8
7.3 The Control Word ....................................... 9
7.4 The Martini Legacy Mode Control Word ................... 10
7.5 PW packet processing ................................... 10
7.5.1 Encapsulation of Frame relay frames .................... 10
7.5.2 Setting the sequence number ............................ 11
7.6 Decapsulation of PW packets ............................ 11
7.6.1 Processing the sequence number ......................... 12
7.6.2 Processing of the Length Field by the Receiver ......... 12
7.7 MPLS Shim EXP Bit Values ............................... 13
7.8 MPLS Shim S Bit Value .................................. 13
7.9 Control Plane Details for Frame Relay Service .......... 13
7.9.1 Frame Relay Specific Interface Parameter sub-TLV ....... 13
8 Frame Relay Port Mode .................................. 14
9 Congestion Control ..................................... 14
10 IANA Considerations .................................... 15
11 Security Considerations ................................ 15
12 Full Copyright Statement ............................... 15
13 Intellectual Property Statement ........................ 16
14 Normative References ................................... 16
15 Informative References ................................. 17
16 Author Information ..................................... 18
17 Contributing Author Information ........................ 19
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1. Specification of Requirements
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.
Below are the definitions for the terms used throughout the document.
PWE3 definitions can be found in [PWE3REQ, RFC3985]. This section
defines terms specific to frame relay.
- Forward direction.
The forward direction is the direction taken by the frame being
forwarded.
- Backward direction.
In frame relay it is the direction opposite to the direction
taken by a frame being forwarded (see also forward direction).
2. Co-authors
The following are co-authors of this document:
Nasser El-Aawar Level 3 Communications, LLC
Eric C. Rosen Cisco Systems
Daniel Tappan Cisco Systems
Thomas K. Johnson Litchfield Communications
Kireeti Kompella Juniper Networks, Inc.
Steve Vogelsang Laurel Networks, Inc.
Vinai Sirkay Reliance Infocomm
Ravi Bhat Nokia
Nishit Vasavada Nokia
Giles Heron Tellabs
Dimitri Stratton Vlachos Mazu Networks,Inc.
Chris Liljenstolpe Cable & Wireless
Prayson Pate Overture Networks, Inc
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3. Acronyms and Abbreviations
BECN Backward Explicit Congestion Notification
CE Customer Edge
C/R Command/Response
DE Discard Eligibility
DLCI Data Link Connection identifier
FCS Frame Check Sequence
FECN Forward Explicit Congestion Notification
FR Frame Relay
LSP Label Switched Path
LSR Label Switching Router
MPLS Multiprotocol Label Switching
MTU Maximum Transfer Unit
NNI Network-Network Interface
PE Provider Edge
PSN Packet Switched Network
PW Pseudo Wire
PWE3 Pseudo Wire Emulation Edge to Edge
POS Packet over SONET/SDH
PVC Permanent Virtual Circuit
QoS Quality of Service
SVC Switched Virtual Circuit
UNI User-Network Interface
VC Virtual Circuit
4. Introduction
In an MPLS or IP network, it is possible to use control protocols
such as those specified in [CONTROL] to set up "Pseudo Wires" that
carry the the Protocol Data Units of layer 2 protocols across the
network. A number of these emulated Pseudo Wires (PW) may be carried
in a single tunnel. The main functions required to support frame
relay PW by a PE include:
- Encapsulation of frame relay specific information in a suitable
pseudo wire (PW) packet,
- Transfer of a PW packet across an MPLS network for delivery to a
peer PE.
- Extraction of frame relay specific information from a PW packet
by the remote peer PE,
- Regeneration of native frame relay frames for forwarding across
an egress port of the remote peer PE,
- Execution of any other operations as required to support frame
relay service.
This document specifies the encapsulation for the emulated frame
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relay VC over an MPLS PSN. Although different layer 2 protocols
require different information to be carried in this encapsulation, an
attempt has been made to make the encapsulation as common as possible
for all layer 2 protocols. Other layer 2 protocols are described in
separate documents. [ATM] [ETH] [PPP]
The following figure describes the reference models which are derived
from [RFC3985] to support the frame relay PW emulated services.
|<-------------- Emulated Service ---------------->|
| |
| |<------- Pseudo Wire ------>| |
| | | |
| | |<-- PSN Tunnel -->| | |
| PW End V V V V PW End |
V Service +----+ +----+ Service V
+-----+ | | PE1|==================| PE2| | +-----+
| |----------|............PW1.............|----------| |
| CE1 | | | | | | | | CE2 |
| |----------|............PW2.............|----------| |
+-----+ ^ | | |==================| | | ^ +-----+
^ | +----+ +----+ | | ^
| | Provider Edge 1 Provider Edge 2 | |
| | (PE1) (PE2) | |
Customer | | Customer
Edge 1 | | Edge 2
| |
| |
Attachment Circuit (AC) Attachment Circuit (AC)
native frame relay service native frame relay service
Figure 1: PWE3 frame relay PVC Interface Reference Configuration
Two mapping modes can be defined between frame relay VCs and pseudo
wires: The first one is called "one-to-one" mapping, because there
is a one-to-one correspondence between a frame relay VC and one
Pseudo Wire. The second mapping is called "many-to-one" mapping or
"port mode" because multiple frame relay VCs assigned to a port are
mapped to one pseudo wire. The "port mode" encapsulation is identical
to HDLC pseudo wire encapsulation which is described in [PPP].
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5. Applicability Statement
Frame Relay over PW service is not intended to perfectly emulate the
traditional frame relay service, but it can be used for applications
that need frame relay transport service.
The following are notable differences between traditional frame relay
service, and the protocol described in this document:
- Frame ordering can be preserved using the OPTIONAL sequence field
in the control word, however implementations are not required to
support this feature.
- The Quality of Service model for traditional frame relay can be
emulated , however this is outside the scope of this document.
- A Frame Relay Port mode PW, does not process any frame relay
status messages or alarms as described in [Q922] [Q933]
- The frame relay BECN, and FECN bit are transparent to the MPLS
network , and cannot reflect the status of the MPLS network.
- Support for frame relay SVC and SPVC is outside the scope of this
document.
- Frame relay LMI is terminated locally in the PE connected to the
frame relay attachment circuit.
- The support of PVC link integrity check is outside the scope of
this document.
6. General encapsulation method
The general frame relay pseudo wire packet format for carrying frame
relay information (user's payload and frame relay control
information) between two PEs is shown in Figure 2.
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+-------------------------------+
| |
| MPLS Transport header |
| (As required) |
+-------------------------------+
| Pseudo Wire (PW) Header |
+-------------------------------+
| Control Word |
+-------------------------------+
| FR Service |
| Payload |
+-------------------------------+
Figure 2 - General format of frame relay encapsulation over PSN
The PW packet consists of the following fields: Control word, and
Payload preceded by the MPLS Transport and pseudo wire header. The
meaning of the different fields is as follows:
-i. MPLS Transport header is specific to the MPLS network. This
header is used to switch the PW packet through the MPLS
core.
-ii. PW header contains an identifier for multiplexing PWs within
an MPLS tunnel.
-iii. Control Word contains protocol control information for
providing a frame relay service. Its structure is provided
in the following sections.
-iv. The contents of the frame relay service payload field
depends on the mapping mode. In general it contains the
layer 2 frame relay frame.
7. Frame Relay over MPLS PSN for the One-to-One Mode
7.1. MPLS PSN Tunnel and PW
MPLS label switched paths (LSPs) called "MPLS Tunnels" are used
between PEs and within the MPLS core network for forwarding purposes
of PW packets. An MPLS tunnel corresponds to "PSN Tunnel" of Figure
1.
Several "Pseudo Wires" may be nested inside one MPLS tunnel. Each PW
carries the traffic of a single frame relay VC. In this case the PW
header is an MPLS label called the PW label.
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7.2. Packet Format over MPLS PSN
For the one-to-one mapping mode for frame relay over an MPLS network,
the PW packet format is shown in Figure 3.
+-------------------------------+
| MPLS Tunnel label(s) | n*4 octets (four octets per label)
+-------------------------------+
| PW label | 4 octets
+-------------------------------+
| Control Word |
| (See Figure 4) | 4 octets
+-------------------------------+
| Payload |
| (Frame relay frame |
| information field) | n octets
| |
+-------------------------------+
Figure 3 - frame relay Over MPLS PSN Packet for the One-to-One
Mapping
The meaning of the different fields is as follows:
- MPLS Tunnel label(s)
The MPLS Tunnel label(s) corresponds to the MPLS transport header
of Figure 2. The label(s) is/are used by MPLS LSRs to forward a
PW packet from one PE to the other.
- PW Label
The PW label identifies one PW (i.e. one LSP) assigned to a frame
relay VC in one direction. It corresponds to the PW header of
Figure 2. Together the MPLS Tunnel label(s) and PW label form an
MPLS label stack [RFC3032].
- Control Word
The Control Word contains protocol control information. Its
structure is shown in Figure 4.
- Payload
The payload field corresponds to X.36/X.76 frame relay frame
information field with bit/byte stuffing, frame relay header
removed, and FCS removed . It is RECOMMENDED to support a frame
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size of at least 1600 bytes. The maximum length of the payload
field MUST be agreed upon by the two PEs. This can be achieved by
using the MTU interface parameter when the PW is established.
[CONTROL]
7.3. The Control Word
The control word defined below is REQUIRED for frame relay one-to-one
mode. The control word carries certain frame relay specific
information that is necessary to regenerate the frame relay frame on
the egress PE. Additionally, the control word also carries a
sequence number that can be used to preserve sequentiality when
carrying frame relay over an MPLS network. Its structure 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0 0 0 0|F|B|D|C|Res| Length | Sequence Number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 4 - Control Word structure for the one-to-one mapping mode
The meaning of the Control Word fields (Figure 4) is as follows (see
also [X36 and X76] for frame relay bits):
- bits 0 to 3
In the above diagram the first 4 bits MUST be set to 0 to
indicate PW data.
- F (bit 4) FR FECN (Forward Explicit Congestion Notification) bit.
- B (bit 5) FR BECN (Backward Explicit Congestion Notification)
bit.
- D (bit 6) FR DE bit (Discard Eligibility) bit.
- C (bit 7) FR frame C/R (Command/Response) bit.
- Res (bits 8 and 9): These bits are reserved and MUST be set to
0 upon transmission and ignored upon reception.
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- Length (bits 10 to 15)
If the Pseudo Wire traverses a network link that requires a
minimum frame size (a notable example is Ethernet), padding is
required to reach its minimum frame size. If the frame's length
(defined as the length of the layer 2 payload plus the length of
the control word) is less than 64 octets, the length field MUST
be set to the PW payload length. Otherwise the length field MUST
be set to zero. The value of the length field, if non-zero, is
used to remove the padding characters by the egress PE.
- Sequence number (Bit 16 to 31)
Sequence numbers provide one possible mechanism to ensure the
ordered delivery of PW packets. The processing of the sequence
number field is OPTIONAL. The sequence number space is a 16 bit,
unsigned circular space. The sequence number value 0 is used to
indicate that the sequence number check algorithm is not used.
7.4. The Martini Legacy Mode Control Word
For backward compatibility to existing implementations the following
version of the control word is defined as the "martini mode CW" for
frame relay.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0 0 0 0|B|F|D|C|Res| Length | Sequence Number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 4 - Control Word structure for the frame relay martini mode
Note that the "B" and "F" bits are reversed.
This control word format is used for PW type "Frame Relay DLCI (
Martini Mode )"
7.5. PW packet processing
7.5.1. Encapsulation of Frame relay frames
The encapsulation process of a frame relay frame is initiated when a
PE receives a frame relay frame from one of its frame relay UNI or
NNI interfaces. The PE generates the following fields of the control
word from the corresponding fields of the frame relay frame as
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follows:
- Command/Response (C/R or C) bit: The C bit is copied unchanged in
the PW Control Word.
- The DE bit of the frame relay frame is copied into the D bit
field. However if the D bit is not already set, it MAY be set as
a result of ingress frame policing. If not already set by the
copy operation, setting of this bit by a PE is OPTIONAL. The PE
MUST NOT clear this bit (set it to 0 if it was received with the
value of 1).
- The FECN bit of the frame relay frame is copied into the F bit
field. However if the F bit is not already set, it MAY be set to
reflect a congestion situation detected by the PE. If not already
set by the copy operation, setting of this bit by a PE is
OPTIONAL. The PE MUST NOT clear this bit (set it to 0 if it was
received with the value of 1).
- The BECN bit of the frame relay frame is copied into the B bit
field. However if the B bit is not already set, it MAY be set to
reflect a congestion situation detected by the PE. If not already
set by the copy operation, setting of this bit by a PE is
OPTIONAL. The PE MUST NOT clear this bit (set it to 0 if it was
received with the value of 1).
- If the PW packet length (defined as the length of the payload
plus the length of the control word) is less than 64 octets, the
length field MUST be set to the packet's length. Otherwise the
length field MUST be set to zero.
- The sequence number field is processed if the PW uses sequence
numbers. [CW]
- The payload of the PW packet is the contents of ITU-T
Recommendations X.36/X.76 [X36] [X76] frame relay frame
information field stripped from any bit or byte stuffing.
7.5.2. Setting the sequence number
For a given PW, and a pair of routers PE1 and PE2, if PE1 supports
packet sequencing then the procedures in [CW] section 4.1 MUST be
followed.
7.6. Decapsulation of PW packets
When a PE receives a PW packet, it processes the different fields of
the control word in order to decapsulate the frame relay frame for
transmission to a CE on a frame relay UNI or NNI. The PE performs the
following actions (not necessarily in the order shown):
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- It generates the following frame relay frame header fields from
the corresponding fields of the PW packet.
- The C/R bit MUST be copied in the frame relay header.
- The D bit MUST be copied into the frame relay header DE bit.
- The F bit MUST be copied into the frame relay header FECN bit. If
the F bit is set to zero, the FECN bit may be set to one,
depending on the congestion state of the PE device in the forward
direction. Changing the state of this bit by a PE is OPTIONAL.
- The B bit MUST be copied into the frame relay header BECN bit. If
the B bit is set to zero, the BECN bit may be set to one,
depending on the congestion state of the PE device in the
backward direction. Changing the state of this bit by a PE is
OPTIONAL.
- It processes the length and sequence field, the details of which
are in the following sub-sections.
- It copies the frame relay information field from the contents of
the PW packet payload after removing any padding.
Once the above fields of a FR frame have been processed, the standard
HDLC operations are performed on the frame relay frame: the HDLC
header is added, any bit or byte stuffing is added as required, and
the FCS is also appended to the frame. The FR frame is then queued
for transmission on the selected frame relay UNI or NNI interface.
7.6.1. Processing the sequence number
If a router PE2 supports receive sequence number processing, then the
procedures in [CW] section 4.2 MUST be used.
7.6.2. Processing of the Length Field by the Receiver
Any padding octet, if present, in the payload field of a PW packet
received MUST be removed before forwarding the data.
- If the Length field is set to zero then there are no padding
octets following the payload field.
- Else if the payload is longer then the length specified in the
control word padding characters are removed based on the length
field.
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7.7. MPLS Shim EXP Bit Values
If it is desired to carry Quality of Service information, the Quality
of Service information SHOULD be represented in the EXP field of the
PW MPLS label. If more than one MPLS label is imposed by the ingress
LSR, the EXP field of any labels higher in the stack SHOULD also
carry the same value.
7.8. MPLS Shim S Bit Value
The ingress LSR, PE1, MUST set the S bit of the PW label to a value
of 1 to denote that the PW label is at the bottom of the stack.
7.9. Control Plane Details for Frame Relay Service
The PE MUST provide frame relay PVC status signaling to the frame
relay network. If the PE detects a service-affecting condition for a
particular DLCI, as defined in [Q933] Q.933 Annex A.5 sited in IA
FRF1.1, the PE MUST communicate to the remote PE the status of the PW
that corresponds to the frame relay DLCI status. The Egress PE SHOULD
generate the corresponding errors and alarms as defined in [Q922]
[Q933] on the egress Frame relay PVC.
There are two frame relay flags to control word bit mappings
described below. The legacy bit ordering scheme will be used for a PW
of type 0x0001 "Frame Relay DLCI (Martini Mode)", while the new bit
ordering scheme will be used for a PW of type 0x0019 "Frame Relay
DLCI". The IANA allocation registry of "Pseudowire Type" is defined
in [IANA] along with initial allocated values.
7.9.1. Frame Relay Specific Interface Parameter sub-TLV
A separate document [CONTROL], describes the PW control, and
maintenance protocol in detail including generic interface parameter
sub-TLVs. The interface parameter information, when applicable, MUST
be used to validate that the PEs, and the ingress and egress ports at
the edges of the circuit, have the necessary capabilities to
interoperate with each other. The Interface parameter TLV is defined
in [CONTROL], the IANA registry with initial values for interface
parameter sub-TLV types is defined in [IANA], but the frame relay
specific interface parameter sub-TLV types are specified as follows:
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- 0x08 Frame Relay Header Length Sub-TLV.
An optional 16 bit value indicating the length of the FR Header
expressed in octets. This OPTIONAL interface parameter Sub-TLV
can have value of 2, 3, or 4, with the default being equal to 2.
If this Sub-TLV is not present the default value of 2 is assumed.
8. Frame Relay Port Mode
Frame relay port mode PW shares the same encapsulation as the HDLC
PW, and is described in the respective document. [PPP]
9. Congestion Control
As explained in [RFC3985], the PSN carrying the PW may be subject to
congestion, with congestion characteristics depending on PSN type,
network architecture, configuration, and loading. During congestion
the PSN may exhibit packet loss that will impact the service carried
by the frame relay PW. In addition, since frame relay PWs carry an
variety of services across the PSN, including but not restricted to
TCP/IP, they may or may not behave in a TCP-friendly manner
prescribed by [RFC2914]. In the presence of services that reduce
transmission rate, frame relay PWs may thus consume more than their
fair share and in that case SHOULD be halted.
Whenever possible, frame relay PWs should be run over traffic-
engineered PSNs providing bandwidth allocation and admission control
mechanisms. IntServ-enabled domains providing the Guaranteed Service
(GS) or DiffServ-enabled domains using EF (expedited forwarding) are
examples of traffic-engineered PSNs. Such PSNs will minimize loss and
delay while providing some degree of isolation of the frame relay
PW's effects from neighboring streams.
It should be noted that when transporting Frame Relay, DiffServ-
enabled domains may use AF (Assured Forwarding) and/or DF (Default
Forwarding) instead of EF, in order to place less burden on the
network and gain additional statistical multiplexing advantage. In
particular, if the CIR of a Frame Relay VC is zero, then it is
equivalent to a best-effort UDP over IP stream regarding congestion -
the network is free to drop frames as necessary. In this case, the
"DF" PHB would be appropriate in a diff-serv-TE domain.
Alternatively, if the CIR of a Frame Relay VC is nonzero and the DE
bit is zero in the FR header, then "AF31" would be appropriate to
use, and if the CIR of a Frame Relay VC is nonzero, but the DE bit is
on, then "AF32" would be appropriate [RFC3270].
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The PEs SHOULD monitor for congestion (by using explicit congestion
notification, [VCCV], or by measuring packet loss) in order to ensure
that the service using the frame relay PW may be maintained. When a
PE detects significant congestion while receiving the PW PDUs, the
BECN bits of the frame relay frame transmitted on the same PW SHOULD
be set to notify the remote PE, and the remote frame relay switch of
the congestion situation. In addition, the FECN bits SHOULD be set in
the FR frames sent out the attachment circuit, to give the FR DTE a
chance to adjust its transport layer advertised window if possible.
If the PW has been set up using the protocol defined in [CONTROL],
then procedures specified in [CONTROL] for status notification can be
used to disable packet transmission on the ingress PE from the egress
PE. The PW may be restarted by manual intervention, or by automatic
means after an appropriate waiting time.
10. IANA Considerations
This document has no IANA Actions.
11. Security Considerations
PWE3 provides no means of protecting the contents or delivery of the
PW packets on behalf of the native service. PWE3 may, however,
leverage security mechanisms provided by the MPLS Tunnel Layer. A
more detailed discussion of PW security is give in [RFC3985, CONTROL,
PWE3REQ].
12. Full Copyright Statement
Copyright (C) The Internet Society (2006).
This document is subject to the rights, licenses and restrictions
contained in BCP 78, and except as set forth therein, the authors
retain all their rights.
This document and the information contained herein are provided on an
"AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET
ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED,
INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE
INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
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13. Intellectual Property Statement
The IETF takes no position regarding the validity or scope of any
Intellectual Property Rights or other rights that might be claimed to
pertain to the implementation or use of the technology described in
this document or the extent to which any license under such rights
might or might not be available; nor does it represent that it has
made any independent effort to identify any such rights. Information
on the procedures with respect to rights in RFC documents can be
found in BCP 78 and BCP 79.
Copies of IPR disclosures made to the IETF Secretariat and any
assurances of licenses to be made available, or the result of an
attempt made to obtain a general license or permission for the use of
such proprietary rights by implementers or users of this
specification can be obtained from the IETF on-line IPR repository at
http://www.ietf.org/ipr.
The IETF invites any interested party to bring to its attention any
copyrights, patents or patent applications, or other proprietary
rights that may cover technology that may be required to implement
this standard. Please address the information to the IETF at ietf-
ipr@ietf.org.
14. Normative References
[CONTROL] Luca Martini, et al., "Pseudowire Setup and Maintenance
using LDP", draft-ietf-pwe3-control-protocol-16.txt,
March 2005, work in progress.
[CW] "PWE3 Control Word for use over an MPLS PSN", S. Bryant,
G. Swallow, D. McPherson, draft-ietf-pwe3-cw-06.txt, ( work in
progress ), October 2005.
[ITUG] ITU Recommendation G.707, "Network Node Interface For The
Synchronous Digital Hierarchy", 1996.
[RFC3032] E. Rosen, et al., RFC 3032, MPLS Label Stack encoding,
January 2001.
[RFC3031] E. Rosen, et al., RFC 3031, MPLS Architecture, January
2001.
[IANA] "IANA Allocations for pseudo Wire Edge to Edge Emulation
(PWE3)" Martini,Townsley, draft-ietf-pwe3-iana-allocation-09.txt
(work in progress), April 2004
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[PPP] "Encapsulation Methods for Transport of PPP/HDLC Over MPLS
Networks", draft-ietf-pwe3-hdlc-ppp-encap-05.txt April 2005
15. Informative References
[RFC3985] Stewart Bryant, et al., PWE3 Architecture,
RFC3985
[VCCV] Nadeau, T., et al."Pseudo Wire Virtual Circuit Connection
Verification (VCCV)", Internet Draft
draft-ietf-pwe3-vccv-08.txt, October 2005. (work in progress)
[FRAG] Andrew G. Malis, et al., PWE3 Fragmentation and
Reassembly, draft-ietf-pwe3-fragmentation-08.txt,
February 2005, ( work in progress ).
[ATM] "Encapsulation Methods for Transport of ATM Over MPLS
Networks", draft-ietf-pwe3-atm-encap-05.txt April 2005
(work in progress)
[ETH] "Encapsulation Methods for Transport of Ethernet Over
MPLS Networks", draft-ietf-pwe3-ethernet-encap-06.txt.
February 2005 (work in progress)
[I233] ITU-T Recommendation I.233.1, ISDN frame relay bearer
service, Geneva, October 1991.
[FRF1] FRF.1.2, Frame relay PVC UNI Implementation Agreement,
Frame Relay Forum, April 2000.
[FRF2] FRF.2.2, Frame relay PVC UNI Implementation Agreement,
Frame Relay Forum, April 2002
[FRF4] FRF.4.1, Frame relay SVC UNI Implementation Agreement,
Frame Relay Forum, January 2000.
[FRF10] FRF.10.1, Frame relay SVC NNI Implementation Agreement,
Frame Relay Forum, January 2000.
[FRF13] FRF.13, Service Level Definition Implementation
Agreement, Frame Relay Forum, August 1998.
[FRF14] FRF.14, Physical layer Implementation Agreement, Frame
Relay Forum, December 1998.
[PWE3REQ] XiPeng Xiao, et al., RFC 3916.
Martini, et al. [Page 17]
Internet Draft draft-ietf-pwe3-frame-relay-07.txt February 2006
[X36] ITU-T Recommendation X.36, Interface between a DTE and
DCE for public data networks providing frame relay,
Geneva, 2000.
[X76] ITU-T Recommendation X.76, Network-to-network interface
between public data networks providing frame relay
services, Geneva,2000.
[Q922] ITU-T Recommendation Q.922 Specification for Frame Mode
Basic call control, ITU Geneva 1995
[Q933] ITU-T Recommendation Q.933 Specification for Frame Mode
Basic call control, ITU Geneva 2003
[RFC2914] S Floyd, rfc2914, "Congestion Control Principles",
September 2000
[RFC3270] F. Le Faucheur, et al., rfc3270,"Multi-Protocol Label
Switching (MPLS) Support of Differentiated Services",May 2002
16. Author Information
Luca Martini
Cisco Systems, Inc.
9155 East Nichols Avenue, Suite 400
Englewood, CO, 80112
e-mail: lmartini@cisco.com
Claude Kawa
OZ Communications
Windsor Station
1100, de la Gauchetie`re St West
Montreal QC Canada
H3B 2S2
e-mail: claude.kawa@oz.com
Andrew G. Malis
Tellabs
90 Rio Robles Dr.
San Jose, CA 95134
e-mail: Andy.Malis@tellabs.com
Martini, et al. [Page 18]
Internet Draft draft-ietf-pwe3-frame-relay-07.txt February 2006
17. Contributing Author Information
Kireeti Kompella
Juniper Networks
1194 N. Mathilda Ave
Sunnyvale, CA 94089
e-mail: kireeti@juniper.net
Giles Heron
Tellabs
Abbey Place
24-28 Easton Street
High Wycombe
Bucks
HP11 1NT
UK
e-mail: giles.heron@tellabs.com
Rao Cherukuri
Juniper Networks
1194 N. Mathilda Ave
Sunnyvale, CA 94089
Dimitri Stratton Vlachos
Mazu Networks, Inc.
125 Cambridgepark Drive
Cambridge, MA 02140
e-mail: d@mazunetworks.com
Chris Liljenstolpe
Cable & Wireless
11700 Plaza America Drive
Reston, VA 20190
e-mail: chris@cw.net
Nasser El-Aawar
Level 3 Communications, LLC.
1025 Eldorado Blvd.
Broomfield, CO, 80021
e-mail: nna@level3.net
Martini, et al. [Page 19]
Internet Draft draft-ietf-pwe3-frame-relay-07.txt February 2006
Eric C. Rosen
Cisco Systems, Inc.
1414 Massachusetts Avenue
Boxborough, MA 01719
e-mail: erosen@cisco.com
Dan Tappan
Cisco Systems, Inc.
1414 Massachusetts Avenue
Boxborough, MA 01719
e-mail: tappan@cisco.com
Prayson Pate
Overture Networks, Inc.
507 Airport Boulevard
Morrisville, NC, USA 27560
e-mail: prayson.pate@overturenetworks.com
David Sinicrope
Ericsson IPI
e-mail: david.sinicrope@ericsson.com
Ravi Bhat
Nokia
e-mail: ravi.bhat@nokia.com
Nishit Vasavada
Nokia
e-mail: nishit.vasavada@nokia.com
Steve Vogelsang
Laurel Networks, Inc.
Omega Corporate Center
1300 Omega Drive
Pittsburgh, PA 15205
e-mail: sjv@laurelnetworks.com
Martini, et al. [Page 20]
Internet Draft draft-ietf-pwe3-frame-relay-07.txt February 2006
Vinai Sirkay
Redback Networks
300 Holger Way,
San Jose, CA 95134
e-mail: sirkay@technologist.com
Martini, et al. [Page 21]
