One document matched: draft-ietf-mpls-tp-cc-cv-rdi-03.txt
Differences from draft-ietf-mpls-tp-cc-cv-rdi-02.txt
MPLS Working Group Dave Allan, Ed.
Internet Draft Ericsson
Intended status: Standards Track
Expires: August 2011 George Swallow Ed.
Cisco Systems, Inc
John Drake Ed.
Juniper
February 2, 2011
Proactive Connectivity Verification, Continuity Check and Remote
Defect indication for MPLS Transport Profile
draft-ietf-mpls-tp-cc-cv-rdi-03
Abstract
Continuity Check (CC), Proactive Connectivity Verification (CV) and
Remote Defect Indication (RDI) functionalities are required for MPLS-
TP OAM.
Continuity Check monitors the integrity of the continuity of the LSP
for any loss of continuity defect. Connectivity verification monitors
the integrity of the routing of the LSP between sink and source for
any connectivity issues. RDI enables an End Point to report, to its
associated End Point, a fault or defect condition that it detects on
a PW, LSP or Section.
This document specifies methods for proactive CV, CC, and RDI for
MPLS-TP Label Switched Path (LSP), PWs and Sections using
Bidirectional Forwarding Detection (BFD).
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 RFC2119 [1].
Status of this Memo
This Internet-Draft is submitted to IETF in full conformance
with the provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet
Engineering Task Force (IETF), its areas, and its working
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groups. Note that other groups may also distribute working
documents as Internet-Drafts.
Internet-Drafts are draft documents valid for a maximum of six
months and may be updated, replaced, or obsoleted by other
documents at any time. It is inappropriate to use Internet-
Drafts as reference material or to cite them other than as "work
in progress".
The list of current Internet-Drafts can be accessed at
http://www.ietf.org/ietf/1id-abstracts.txt.
The list of Internet-Draft Shadow Directories can be accessed at
http://www.ietf.org/shadow.html.
This Internet-Draft will expire on August 2nd 2011.
Copyright Notice
Copyright (c) 2011 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
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Table of Contents
1. Introduction...................................................3
1.1. Authors......................................................4
2. Conventions used in this document..............................4
2.1. Terminology..................................................4
3. MPLS CC, proactive CV and RDI Mechanism using BFD..............5
3.1. ACH code points for CC and proactive CV......................6
3.2. MPLS BFD CC Message format...................................6
3.3. MPLS BFD proactive CV Message format.........................7
3.3.1. ICC-based MEP-ID...........................................8
3.3.2. LSP MEP-ID.................................................8
3.3.3. PW Endpoint MEP-ID.........................................8
3.4. BFD Session in MPLS-TP terminology...........................8
3.5. BFD Profile for MPLS-TP......................................9
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3.5.1. Session initiation........................................10
3.5.2. Defect entry criteria.....................................10
3.5.3. Defect entry consequent action............................11
3.5.4. Defect exit criteria......................................12
3.5.5. State machines............................................12
3.5.6. Configuration of MPLS-TP BFD sessions.....................15
3.5.7. Discriminator values......................................15
4. Acknowledgments...............................................16
5. IANA Considerations...........................................16
6. Security Considerations.......................................16
7. References....................................................16
7.1. Normative References........................................16
7.2. Informative References......................................17
1. Introduction
In traditional transport networks, circuits are provisioned on two or
more switches. Service Providers (SP) need OAM tools to detect mis-
connectivity and loss of continuity of transport circuits. Both PWs
and MPLS-TP LSPs [10] emulating traditional transport circuits need
to provide the same CC and proactive CV capabilities as required in
RFC 5860[3]. This document describes the use of BFD for CC, proactive
CV, and RDI of a PW, LSP or SPME between two Maintenance Entity Group
End Points (MEPs).
As described in [11], Continuity Check (CC) and Proactive
Connectivity Verification (CV) functions are used to detect loss of
continuity (LOC), and unintended connectivity between two MEPs (e.g.
mismerging or misconnectivity or unexpected MEP).
The Remote Defect Indication (RDI) is an indicator that is
transmitted by a MEP to communicate to its peer MEP that a signal
fail condition exists. RDI is only used for bidirectional LSPs and is
associated with proactive CC & CV packet generation.
This document specifies the BFD extension and behavior to satisfy the
CC, proactive CV monitoring and the RDI functional requirements for
both co-routed and associated bi-directional LSPs. Supported
encapsulations include GAL/G-ACh, VCCV and UDP/IP. Procedures for
uni-directional LSPs are for further study.
The mechanisms specified in this document are restricted to BFD
asynchronous mode.
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1.1. Authors
David Allan, John Drake, George Swallow, Annamaria Fulignoli, Sami
Boutros, Siva Sivabalan, David Ward, Martin Vigoureux.
2. Conventions used in this document
2.1. Terminology
ACH: Associated Channel Header
BFD: Bidirectional Forwarding Detection
CV: Connectivity Verification
GAL: Generalized Alert Label
LDI: Link Down Indication
LKI: Lock Instruct
LKR: Lock Report
LSR: Label Switching Router
MEG: Maintenance Entity Group
MEP: Maintenance Entity Group End Point
MIP: Maintenance Entity Group Intermediate Point
MPLS-OAM: MPLS Operations, Administration and Maintenance
MPLS-TP: MPLS Transport Profile
MPLS-TP LSP: Uni-directional or Bidirectional Label Switch Path
representing a circuit
MS-PW: Multi-Segment PseudoWire
NMS: Network Management System
PW: Pseudo Wire
RDI: Remote Defect Indication.
SPME: Sub-Path Maintenance Entity
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TTL: Time To Live
TLV: Type Length Value
VCCV: Virtual Circuit Connectivity Verification
3. MPLS CC, proactive CV and RDI Mechanism using BFD
This document proposes distinct encapsulations and code points for
ACh encapsulated BFD depending on whether the mode of operation is CC
or CV:
o CC mode: defines a new code point in the Associated Channel Header
(ACH) described in RFC 5586[2].In this mode Continuity Check and
RDI functionalities are supported.
o CV mode: defines a new code point in the Associated Channel Header
(ACH) described in RFC 5586[2]. The ACH with "MPLS Proactive CV"
code point indicates that the message is an MPLS BFD proactive CV
and CC message and CC, CV and RDI functionalities are supported.
RDI: is communicated via the BFD diagnostic field in BFD CC and CV
messages. It is not a distinct PDU. A sink MEP will encode a
diagnostic code of "1- Control detection time expired" when the
interval times detect multipler have been exceeded, and with "3 -
neighbor signaled session down" as a consequence of the sink MEP
receiving AIS with LDI set. A sink MEP that has started sending diag
code 3 will NOT change it to 1 when the detection timer expires.
In accordance with RFC 5586[2], when these packets are encapsulated
in an IP header, the fields in the IP header are set as defined in
RFC 5884[8]. Further existing ACh code points and mechanisms for BFD
VCCV are specified in RFC5885[7]. These MAY be applied to
Pseudowires by configuration. Also by configuration, the BFD PW-ACH-
encapsulated for PW fault detection only encapsulation can be applied
to bi-directional LSPs by employing the GAL to indicate the presence
of the ACh.
A further artifact of IP encapsulation is that CV mis-connectivity
defect detection can be performed by inferring MEP_ID on the basis of
the combination of the source IP address and "my discriminator"
fields.
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3.1. ACH code points for CC and proactive CV
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 1|Version| Flags |0xHH BFD CC/CV Code Point |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 1: ACH Indication of MPLS-TP Connectivity Verification
The first nibble (0001b) indicates the ACH.
The version and the flags are set to 0 as specified in [2].
The code point is either
- BFD CC code point = 0xHH. [HH to be assigned by IANA from the PW
Associated Channel Type registry.] or,
- BFD proactive CV code point = 0xHH. [HH to be assigned by IANA from
the PW Associated Channel Type registry.]
Both CC and CV modes apply to PWs, MPLS LSPs (including SPMEs), and
Sections.
CC and CV operation can be simultaneously employed on an ME within a
single BFD session. The expected usage is that normal operation is to
send CC BFD PDUs with every nth BFD PDU augmented with a source MEP-
ID and identified as requiring additional processing by the different
ACh channel type. When CC and CV are interleaved, the minimum
insertion interval for CV PDUs is one per second.
3.2. MPLS BFD CC Message format
The format of an MPLS CC Message is shown 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0 0 0 1|Version| Flags | 0xHH BFD CC Code point |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
~ BFD Control Packet ~
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2: MPLS CC Message
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3.3. MPLS BFD proactive CV Message format
The format of an MPLS CV Message is shown 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0 0 0 1|Version| Flags | 0xHH BFD CV Code Point |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
~ BFD Control Packet ~
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
~ Unique MEP-ID of source of the BFD packet ~
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 3: MPLS CV Message
As shown in Figure 3, BFD Control packet as defined in [4] is
transmitted as MPLS labeled packets along with the ACH. Appended to
the BFD control packet is a MEP Source ID TLV.
A MEP Source ID TLV is encoded as a 2 octet field that specifies a
Type, followed by a 2 octet Length Field, followed by a variable
length Value field.
The length in the BFD control packet is as per [4]. There are 3
Source MEP TLVs (corresponding to the MEP-IDs defined in Error!
Reference source not found. [type fields to be assigned by IANA]. The
type fields are:
X1 - ICC encoded MEP-ID
X2 - LSP MEP-ID
X3 - PW MEP-ID
When GAL label is used, the TTL field of the GAL MUST be set to at
least 1, and the GAL will be the end of stack label (S=1).
A node MUST NOT change the value in the MEP Source ID TLV.
When digest based authentication is used, the Source ID TLV MUST NOT
be included in the digest
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3.3.1. ICC-based MEP-ID
As defined in [9], the ICC-based MEP_ID consists of the MEG_ID, a
string of up to 13 characters (A-Z and 0-9), followed by the MEP
Index, an unsigned 16 bit integer that MUST be unique within the
context of the MEG_ID.
3.3.2. LSP MEP-ID
As defined in [9], the MPLS_TP LSP MEP-ID consists of the Node
Identifier, a thirty two bit identifier that MUST be unique within
the context of an operator's network, followed by the Tunnel_Num, an
unsigned sixteen bit integer that MUST be unique within the context
of the Node Identifier, and the LSP_NUM, an unsigned sixteen bit
integer that MUST be unique with the context of the Tunnel Num.
3.3.3. PW Endpoint MEP-ID
As defined in [9], the PW Endpoint MEP-ID consists of the Node
Identifier, a thirty two bit identifier that MUST be unique within
the context of an operator's network, followed by the AC_ID, a thirty
two bit identifier that MUST be unique within the context of the Node
Identifier.
In situations where global uniqueness is required, the Node
Identifier is preceded by the Global ID, a thirty two bit identifier
that contains the two-octet (right hand justified and preceded by
sixteen bits of zero) or four-octet value of the operator's
Autonomous System Number (ASN).
3.4. BFD Session in MPLS-TP terminology
A BFD session corresponds to a CC or a proactive CV OAM instance in
MPLS-TP terminology.
A BFD session is enabled when the CC or proactive CV functionality is
enabled on a configured Maintenance Entity (ME)..
On a Sink MEP, a BFD session can be in DOWN, INIT or UP state as
detailed in [4].
When on a ME the CC or proactive CV functionality is disabled, the
BFD session transitions to the ADMIN DOWN State and the BFD session
ends.
A new BFD session is initiated when the operator enables or re-
enables the CC or CV functionality on the same ME.
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3.5. BFD Profile for MPLS-TP
BFD MUST operate in asynchronous mode. In this mode, the BFD Control
packets are periodically sent at configurable time rate. This rate is
typically a fixed value for the lifetime of the session. In the rare
circumstance where an operator has a reason to change session
parameters, the session MUST be moved to the ADMIN DOWN state.
Poll/final discipline can only used for VCCV and UDP/IP encapsulated
BFD.
This document specifies bi-directional BFD for p2p transport LSPs,
hence the M bit MUST be clear.
There are two modes of operation for bi-directional LSPs. One in
which the session state of both directions of the LSP is coordinated
and one constructed from BFD sessions in such a way that the two
directions operate independently. A single bi-directional BFD session
is used for coordinated operation. Two independent BFD sessions are
used for independent operation.
Coordinated operation is as described in [4]. Independent operation
requires clarification of two aspects of [4]. Independent operation
is characterized by the setting of MinRxInterval to zero by the MEP
that is typically the session originator (referred to as the source
MEP), and there will be a session originator at either end of the bi-
directional LSP. Each source MEP will have a corresponding sink MEP
that has been configured to a Tx interval of zero.
The base spec is unclear on aspects of how a MEP with a BFD transmit
rate set to zero behaves. One interpretation is that no periodic
messages on the reverse component of the bi-directional LSP originate
with that MEP, it will only originate messages on a state change.
The first clarification is that when a state change occurs a MEP set
to a transmit rate of zero sends BFD control messages with a one
second period on the reverse component until such time that the state
change is confirmed by the session peer. At this point the MEP set to
a transmit rate of zero can resume quiescent behavior. This adds
robustness to all state transitions in the RxInterval=0 case.
The second is that the originating MEP (the one with a non-zero
TxInterval) will ignore a DOWN state received from a zero interval
peer. This means that the zero interval peer will continue to send
DOWN state messages that include the RDI diagnostic code as the state
change is never confirmed. This adds robustness to the exchange of
RDI indication on a uni-directional failure (for both session types
DOWN with a diagnostic of either control detection period expired or
neighbor signaled session down offering RDI functionality).
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A further extension to the base specification is that there are
additional OAM protocol exchanges that act as inputs to the BFD state
machine; these are the Link Down Indication [5] and the Lock
Instruct/Lock Report transactions; Lock Report interaction being
optional.
3.5.1. Session initiation
In all scenarios a BFD session starts with both ends in the DOWN
state. DOWN state messages exchanged include the desired Tx and Rx
rates for the session. If a node cannot support the Min Tx rate
desired by a peer MEP it does not transition from down to the INIT
state and sends a diagnostic code of configuration error (to be
assigned by IANA) indicating that the requested Tx rate cannot be
supported.
Otherwise once a transition from DOWN to INIT has occurred, the
session progresses as per [4]. In both the DOWN and INIT states
messages are transmitted at a rate of one per second and the defect
detection interval is fixed at 3.5 seconds. On transition to the UP
state, message periodicity changes to the negotiated and/or
configured rate and the detect interval switches to detect multiplier
times the session peer's Tx Rate.
3.5.2. Defect entry criteria
There are further defect criteria beyond those that are defined in
[4] to consider given the possibility of mis-connectivity and mis-
configuration defects. The result is the criteria for a LSP direction
to transition from the defect free state to a defect state is a
superset of that in the BFD base specification [4].
The following conditions cause a MEP to enter the defect state for CC
or CV:
1. BFD session times out (Loss of Continuity defect).
2. Receipt of a link down indication.
3. Receipt of an unexpected M bit (Session Mis-configuration
defect).
And the following will cause the MEP to enter the defect state for CV
operation
1. BFD control packets are received with an unexpected
encapsulation (mis-connectivity defect), these include:
- a PW receiving a packet with a GAL
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- receiving an IP encoded CC or CV packet on a LSP configured
to use GAL/GaCH, or vice versa
(note there are other possibilities that can also alias as an
OAM packet)
2. Receipt of an unexpected globally unique Source MEP identifier
(Mis-connectivity defect).
3. Receipt of an unexpected session discriminator in the your
discriminator field (mis-connectivity defect).
4. Receipt of an expected session discriminator with an unexpected
label (mis-connectivity defect).
5. IF BFD authentication is used, receipt of a message with
incorrect authentication information (password, MD5 digest, or
SHA1 hash).
The effective defect hierarchy (order of checking) is
1. Receiving nothing.
2. Receiving link down indication.
3. Receiving from an incorrect source (determined by whatever
means).
4. Receiving from a correct source (as near as can be determined),
but with incorrect session information).
5. Receiving control packets in all discernable ways correct.
3.5.3. Defect entry consequent action
Upon defect entry a sink MEP will assert signal fail into any client
(sub-)layers. It will also communicate session DOWN to its session
peer.
The blocking of traffic as consequent action MUST be driven only by a
defect's consequent action as specified in draft-ietf-mpls-tp-oam-
framework [11] section 5.1.1.2.
When the defect is mis-branching, the LSP termination will silently
discard all non-oam traffic received.
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3.5.4. Defect exit criteria
3.5.4.1. Exit from a Loss of continuity defect
For a coordinated session, exit from a loss of connectivity defect is
as described in figure 4 which updates [4].
For an independent session, exit from a loss of connectivity defect
occurs upon receipt of a well formed control packet from the peer MEP
as described in figures 5 and 6.
3.5.4.2. Exit from a session mis-configuration defect
Exit from a misconfiguration defect occurs when two consecutive CC or
CV frames have been received with the expected M bit setting.
3.5.4.3. Exit from a mis-connectivity defect
Exit from a mis-connectivity defect state occurs when no CV messages
have been received with an incorrect source MEP-ID for a period of
3.5 seconds.
3.5.5. State machines
The following state machines update [4]. They have been modified to
include AIS with LDI set and LKI as specified in [5] as inputs to the
state machine and to clarify the behavior for independent mode. LKR
is an optional input.
The coordinated session state machine has been augmented to indicate
AIS with LDI set and optionally LKR as inputs to the state machine.
For a session that is in the UP state, receipt of AIS with LDI set or
optionally LKR will transition the session into the DOWN state.
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+--+
| | UP, ADMIN DOWN, TIMER, AIS-LDI, LKR
| V
DOWN +------+ INIT
+------------| |------------+
| | DOWN | |
| +-------->| |<--------+ |
| | +------+ | |
| | | |
| | ADMIN DOWN,| |
| |ADMIN DOWN, DOWN,| |
| |TIMER TIMER,| |
V |AIS-LDI,LKR AIS-LDI,LKR | V
+------+ +------+
+----| | | |----+
DOWN| | INIT |--------------------->| UP | |INIT, UP
+--->| | INIT, UP | |<---+
+------+ +------+
Figure 4: State machine for coordinated session operation
For independent mode, there are two state machines. One for the
source MEP (who requested MinRxInterval=0) and the sink MEP (who
agreed to MinRxInterval=0).
The source MEP will not transition out of the UP state once
initialized except in the case of a forced ADMIN DOWN. Hence AIS-with
LDI set and optionally LKR do not enter into the state machine
transition from the UP state, but do enter into the INIT and DOWN
states.
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+--+
| | UP, ADMIN DOWN, TIMER
| V
DOWN +------+ INIT
+------------| |------------+
| | DOWN | |
| +-------->| |<--------+ |
| | +------+ | |
| | | |
| |ADMIN DOWN ADMIN DOWN | |
| |TIMER, | |
| |AIS-LDI, | |
V |LKR | V
+------+ +------+
+----| | | |----+
DOWN| | INIT |--------------------->| UP | | INIT, UP, DOWN,
+--->| | INIT, UP | |<---+ AIS-LDI, LKR
+------+ +------+
Figure 5: State machine for source MEP for independent session
operation
The sink MEP state machine (for which the transmit interval has been
set to zero) is modified to:
1) Permit direct transition from DOWN to UP once the session has been
initialized. With the exception of via the ADMIN DOWN state, the
source MEP will never transition from the UP state, hence in normal
unidirectional fault scenarios will never transition to the INIT
state.
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+--+
| | ADMIN DOWN, TIMER, AIS-LDI, LKR
| V
DOWN +------+ INIT, UP
+------------| |------------+
| | DOWN | |
| +-------->| |<--------+ |
| | +------+ | |
| | | |
| | ADMIN DOWN,| |
| |ADMIN DOWN, TIMER, | |
| |TIMER, DOWN, | |
| |AIS-LDI, AIS-LDI, | V
V |LKR LKR | |
+------+ +------+
+----| | | |----+
DOWN| | INIT |--------------------->| UP | |INIT, UP
+--->| | INIT, UP | |<---+
+------+ +------+
Figure 6: State machine for the sink MEP for independent session
operation
3.5.6. Configuration of MPLS-TP BFD sessions
Configuration of MPLS-TP BFD session paramters and coordination of
same between the source and sink MEPs is out of scope of this memo.
3.5.7. Discriminator values
In the BFD control packet the discriminator values have either local
to the sink MEP or no significance (when not known).
My Discriminator field MUST be set to a nonzero value (it can be a
fixed value), the transmitted your discriminator value MUST reflect
back the received value of My discriminator field or be set to 0 if
that value is not known.
Per RFC5884 Section 7 [8], a node MUST NOT change the value of the
"my discriminator" field for an established BFD session.
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4. Acknowledgments
Nitin Bahadur, Rahul Aggarwal, Dave Ward, Tom Nadeau, Nurit
Sprecher and Yaacov Weingarten also contributed to this
document.
5. IANA Considerations
This draft requires the allocation of two channel types from the
the IANA "PW Associated Channel Type" registry in RFC4446 [6].
Xx MPLS-TP CC message
Xx+1 MPLS-TP CV message
This draft requires the creations of a source MEP-ID TLV
registry with initial values of:
Xx - ICC encoded MEP-ID
Xx+1 - LSP MEP-ID
Xx+2 - PW MEP-ID
The source MEP-ID TLV will require standards action registration
procedures for additional values.
This memo requests a code point from the registry for BFD
diagnostic codes [4]:
Xx - configuration error
6. Security Considerations
Base BFD foresees an optional authentication section (see [4]
section 6.7); that can be applied to this application.
7. References
7.1. Normative References
[1] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[2] Bocci, M. et al., " MPLS Generic Associated Channel ", RFC
5586 , June 2009
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[3] Vigoureux, M., Betts, M. and D. Ward, "Requirements for
Operations Administration and Maintenance in MPLS
Transport Networks", RFC5860, May 2010
[4] Katz, D. and D. Ward, "Bidirectional Forwarding
Detection", RFC 5880, June 2010
[5] Swallow, G. et al., "MPLS Fault Management OAM", draft-
ietf-mpls-tp-fault-03 (work in progress), October 2010
[6] Martini, L., " IANA Allocations for Pseudowire Edge to
Edge Emulation (PWE3)", RFC 4446, April 2006
[7] Nadeau, T. et al. "Bidirectional Forwarding Detection
(BFD) for the Pseudowire Virtual Circuit Connectivity
Verification (VCCV) ", IETF RFC 5885, June 2010
[8] Aggarwal, R. et.al., "Bidirectional Forwarding Detection
(BFD) for MPLS Label Switched Paths (LSPs)", RFC 5884,
June 2010
[9] Bocci, M. and G. Swallow, "MPLS-TP Identifiers", draft-
ietf-mpls-tp-identifiers-03 (work in progress), October
2010
7.2. Informative References
[10] Bocci, M., et al., "A Framework for MPLS in Transport
Networks", RFC5921, July 2010
[11] Allan, D., and Busi, I. "MPLS-TP OAM Framework", draft-
ietf-mpls-tp-oam-framework-10 (work in progress), December
2010
Allan et al., Expires August, 2011 [Page 17]
Internet-Draft draft-ietf-mpls-tp-cc-cv-rdi-03 February 2011
Authors' Addresses
Dave Allan
Ericsson
Email: david.i.allan@ericsson.com
John Drake
Juniper
Email: jdrake@juniper.net
George Swallow
Cisco Systems, Inc.
Email: swallow@cisco.com
Annamaria Fulignoli
Ericsson
Email: annamaria.fulignoli@ericsson.com
Sami Boutros
Cisco Systems, Inc.
Email: sboutros@cisco.com
Martin Vigoureux
Alcatel-Lucent
Email: martin.vigoureux@alcatel-lucent.com
Siva Sivabalan
Cisco Systems, Inc.
Email: msiva@cisco.com
David Ward
Juniper
Email: dward@juniper.net
Allan et al., Expires August, 2011 [Page 18]
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