Internet Engineering Task Force (IETF) E. Bellagamba
Request for Comments: 7487 A. Takacs
Category: Standards Track G. Mirsky
ISSN: 2070-1721 Ericsson
L. Andersson
Huawei Technologies
P. Skoldstrom
Acreo AB
D. Ward
Cisco
March 2015
Configuration of Proactive Operations, Administration, and Maintenance
(OAM) Functions for MPLS-Based Transport Networks Using RSVP-TE
Abstract
This specification describes the configuration of proactive MPLS
Transport Profile (MPLS-TP) Operations, Administration, and
Maintenance (OAM) functions for a given Label Switched Path (LSP)
using a set of TLVs that are carried by the GMPLS RSVP-TE protocol
based on the OAM Configuration Framework for GMPLS RSVP-TE.
Status of This Memo
This is an Internet Standards Track document.
This document is a product of the Internet Engineering Task Force
(IETF). It represents the consensus of the IETF community. It has
received public review and has been approved for publication by the
Internet Engineering Steering Group (IESG). Further information on
Internet Standards is available in Section 2 of RFC 5741.
Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
http://www.rfc-editor.org/info/rfc7487.
Copyright Notice
Copyright (c) 2015 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
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the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Conventions Used in This Document . . . . . . . . . . . . 4
1.1.1. Terminology . . . . . . . . . . . . . . . . . . . . . 4
1.1.2. Requirements Language . . . . . . . . . . . . . . . . 5
2. Overview of MPLS OAM for Transport Applications . . . . . . . 5
3. Theory of Operations . . . . . . . . . . . . . . . . . . . . 5 6
3.1. MPLS-TP OAM Configuration Operation Overview . . . . . . 5 6
3.1.1. Configuration of BFD Sessions . . . . . . . . . . . . 6
3.1.2. Configuration of Performance Monitoring . . . . . . . 7
3.1.3. Configuration of Fault Management Signals . . . . . . 7 8
3.2. MPLS OAM Configuration Sub-TLV . . . . . . . . . . . . . 8
3.2.1. CV Flag Rules of Use . . . . . . . . . . . . . . . . 10
3.3. BFD Configuration Sub-TLV . . . . . . . . . . . . . . . . 10 11
3.3.1. BFD Identifiers Sub-TLV . . . . . . . . . . . . . . . 12
3.3.2. Negotiation Timer Parameters Sub-TLV . . . . . . . . 13
3.3.3. BFD Authentication Sub-TLV . . . . . . . . . . . . . 14
3.3.4. Traffic Class Sub-TLV . . . . . . . . . . . . . . . . 15
3.4. Performance Monitoring Sub-TLV . . . . . . . . . . . . . 16
3.4.1. MPLS OAM PM Loss Sub-TLV . . . . . . . . . . . . . . 17 18
3.4.2. MPLS OAM PM Delay Sub-TLV . . . . . . . . . . . . . . 19
3.5. MPLS OAM FMS Sub-TLV . . . . . . . . . . . . . . . . . . 20
4. Summary of MPLS OAM Configuration Errors . . . . . . . . . . 21 22
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 22 23
5.1. MPLS OAM Type . . . . . . . . . . . . . . . . . . . . . . 23
5.2. MPLS OAM Configuration Sub-TLV . . . . . . . . . . . . . 23
5.3. MPLS OAM Configuration Sub-TLV Types . . . . . . . . . . 23 24
5.4. BFD Configuration Sub-TLV Types . . . . . . . . . . . . . 24
5.5. Performance Monitoring Sub-TLV Types . . . . . . . . . . 24 25
5.6. New RSVP-TE Error Codes . . . . . . . . . . . . . . . . . 25
6. Security Considerations . . . . . . . . . . . . . . . . . . . 26
7. References . . . . . . . . . . . . . . . . . . . . . . . . . 26
7.1. Normative References . . . . . . . . . . . . . . . . . . 26 27
7.2. Informative References . . . . . . . . . . . . . . . . . 27 28
Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 29
Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 29
1. Introduction
This document describes the configuration of proactive MPLS-TP OAM
functions for a given LSP using TLVs that use GMPLS RSVP-TE
[RFC3473]. [RFC7260] defines use of GMPLS RSVP-TE for the
configuration of OAM functions in a technology-agnostic way. This
document specifies the additional mechanisms necessary to establish
MPLS-TP OAM entities at the maintenance points for monitoring and
performing measurements on an LSP, as well as defining information
elements and procedures to configure proactive MPLS-TP OAM functions
running between Label Edge Routers (LERs). Initialization and
control of on-demand MPLS-TP OAM functions are expected to be carried
out by directly accessing network nodes via a management interface;
hence, configuration and control of on-demand OAM functions are out
of scope for this document.
MPLS-TP, the Transport Profile of MPLS, must, by definition
[RFC5654], be capable of operating without a control plane.
Therefore, there are several options for configuring MPLS-TP OAM
without a control plane by using either a Network Management System
(NMS), an LSP Ping, or signaling protocols such as RSVP-TE in the
control plane.
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. [RFC5860] defines the requirements for the OAM
functionality of MPLS-TP.
Proactive MPLS-TP OAM is performed by three different protocols:
Bidirectional Forwarding Detection (BFD) [RFC6428] for Continuity
Check / Connectivity Verification, the Delay Measurement (DM)
protocol [RFC6374] for delay and delay variation (jitter)
measurements, and the Loss Measurement (LM) protocol [RFC6374] for
packet loss and throughput measurements. Additionally, there are a
number of Fault Management Signals signals that can be configured [RFC6427].
BFD is a protocol that provides low-overhead, fast 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 and to
detect the data plane failures of MPLS-TP point to point and might
also be extended to support point-to-multipoint connections.
The delay and loss measurement protocols [RFC6374] use a simple
query/response model for performing bidirectional measurements that
allows the originating node to measure packet loss and delay in both
directions. By timestamping and/or writing current packet counters
to the measurement packets four times (Tx and Rx in both directions),
current delays and packet losses can be calculated. By performing
successive delay measurements, the delay variation (jitter) can be
calculated. Current throughput can be calculated from the packet
loss measurements by dividing the number of packets sent/received
with the time it took to perform the measurement, given by the
timestamp in LM header. Combined with a packet generator, the
throughput measurement can be used to measure the maximum capacity of
a particular LSP. It should be noted that here we are not
configuring on-demand throughput estimates based on saturating the
connection as defined in [RFC6371]. Rather, we only enable the
estimation of the current throughput based on loss measurements.
1.1. Conventions Used in This Document
1.1.1. Terminology
AIS - Alarm Indication Signal
BFD - Bidirectional Forwarding Detection
CC - Continuity Check
CV - Connectivity Verification
DM - Delay Measurement
FMS - Fault Management Signal
G-ACh - Generic Associated Channel
GMPLS - Generalized Multi-Protocol Label Switching
LDI - Link Down Indication
LER - Label Edge Router
LKR - Lock Report
LM - Loss Measurement
LOC - Loss Of Continuity
LSP - Label Switched Path
LSR - Label Switching Router
MEP - Maintenance Entity Group End Point
MIP - Maintenance Entity Group Intermediate Point
MPLS - Multi-Protocol Label Switching
MPLS-TP - MPLS Transport Profile
NMS - Network Management System
PM - Performance Measurement
RSVP-TE - Reservation Protocol Traffic Engineering
TC - Traffic Class
1.1.2. 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 [RFC2119].
2. Overview of MPLS OAM for Transport Applications
[RFC6371] describes how MPLS-TP OAM mechanisms are operated to meet
transport requirements outlined in [RFC5860].
[RFC6428] specifies two BFD operation modes: 1) "CC mode", which uses
periodic BFD message exchanges with symmetric timer settings
supporting Continuity Check, and 2) "CV/CC mode", which sends unique
maintenance entity identifiers in the periodic BFD messages
supporting CV as well as CC.
[RFC6374] specifies mechanisms for performance monitoring Performance Monitoring of LSPs, in
particular it specifies loss and delay measurement OAM functions.
[RFC6427] specifies fault management signals with which a server LSP
can notify client LSPs about various fault conditions to suppress
alarms or to be used as triggers for actions in the client LSPs. The
following signals are defined: Alarm Indication Signal (AIS), Link
Down Indication (LDI), and Lock Report (LKR).
[RFC6371] describes the mapping of fault conditions to consequent
actions. Some of these mappings may be configured by the operator
depending on the application of the LSP. The following defects are
identified: Loss Of Continuity (LOC), Misconnectivity, MEP
Misconfiguration, and Period Misconfiguration. Out of these defect
conditions, the following consequent actions may be configurable: 1)
whether or not the LOC defect should result in blocking the outgoing
data traffic; 2) whether or not the "Period Misconfiguration defect"
should result in a signal fail condition.
3. Theory of Operations
3.1. MPLS-TP OAM Configuration Operation Overview
GMPLS RSVP-TE, or alternatively LSP Ping [LSP-PING-CONF], can be used
to simply enable the different OAM functions by setting the
corresponding flags in the "OAM OAM Function Flags Sub-TLV" Sub-TLV [RFC7260]. For
a more detailed configuration, one may include sub-TLVs for the
different OAM functions in order to specify various parameters in
detail.
Typically, intermediate nodes SHOULD NOT process or modify any of the
OAM Configuration TLVs but simply forward them to the end node.
There is one exception to this and that is if the "MPLS MPLS OAM FMS Sub-
TLV"
TLV is present. This sub-TLV MUST be examined even by intermediate
nodes that support these extensions but only acted upon by nodes
capable of transmitting FMS signals into the LSP being established.
The sub-TLV MAY be present when the FMS flag is set in the "OAM OAM
Function Flags Sub-TLV". Sub-TLV. If this sub-TLV is present, then the "OAM
MIP entities desired" and "OAM MEP entities desired" flags (described
in [RFC7260]) in the "LSP LSP Attribute Flags TLV" TLV MUST be set and the
entire OAM Configuration TLV placed either in the
LSP_REQUIRED_ATTRIBUTES object or in the LSP_ATTRIBUTES object in
order to ensure that capable intermediate nodes process the
configuration. If placed in the LSP_ATTRIBUTES object, nodes that
are not able to process the OAM Configuration TLV will forward the
message without generating an error. If the "MPLS MPLS OAM FMS Sub-TLV" Sub-TLV has
been placed in the LSP_REQUIRED_ATTRIBUTES object, a node that
supports RFC 7260 but does not support the "MPLS MPLS OAM FMS Sub-TLV" Sub-TLV MUST
generate a PathErr message with "OAM Problem/Configuration Error"
[RFC7260]. Otherwise, if the node doesn't support RFC 7260, it will
not raise any errors as described in the Section 4.1 of [RFC7260].
Finally, if the "MPLS MPLS OAM FMS Sub-TLV" Sub-TLV is not included, only the "OAM
MEP entities desired" flag is set and the OAM Configuration TLV may
be placed in either LSP_ATTRIBUTES or LSP_REQUIRED_ATTRIBUTES.
3.1.1. Configuration of BFD Sessions
For this specification, BFD MUST be run in either one of the two
modes:
o Asynchronous mode, where both sides should be in active mode; or
o Unidirectional mode.
In the simplest scenario, RSVP-TE (or alternatively LSP Ping
[LSP-PING-CONF]), is used only to bootstrap a BFD session for an LSP
without any timer negotiation.
Timer negotiation can be performed either in subsequent BFD control Control
messages (in this case the operation is similar to LSP-Ping-based
bootstrapping described in [RFC5884]) or directly in the RSVP-TE
signaling messages.
When BFD Control packets are transported in the G-ACh, they are not
protected by any end-to-end checksum; only lower layers are providing
error detection/correction. A single bit error, e.g., a flipped bit
in the BFD State field, could cause the receiving end to wrongly
conclude that the link is down and, in turn, trigger protection
switching. To prevent this from happening, the "BFD BFD Configuration
Sub-TLV"
Sub-TLV has an Integrity flag that, when set, enables BFD
Authentication using Keyed SHA1 with an empty key (all 0s) [RFC5880].
This would ensure that every BFD Control packet carries a SHA1 hash
of itself that can be used to detect errors.
If BFD Authentication using a pre-shared key / password is desired
(i.e., authentication and not only error detection), the "BFD BFD
Authentication Sub-TLV" Sub-TLV MUST be included in the "BFD BFD Configuration
Sub-TLV". Sub-
TLV. The "BFD BFD Authentication Sub-TLV" Sub-TLV is used to specify which
authentication method should be used and which pre-shared key /
password should be used for this particular session. How the key
exchange is performed is out of scope of this document.
3.1.2. Configuration of Performance Monitoring
It is possible to configure Performance Monitoring functionalities
such as Loss, Delay, Delay variation (jitter), and Throughput, as
described in [RFC6374].
When configuring Performance monitoring Monitoring functionalities, it is
possible to choose either the default configuration (by only setting
the respective flags in the "OAM OAM Function Flags Sub-TLV") Sub-TLV) or a
customized configuration. To customize the configuration, one would
set the respective flags and include the respective Loss and/or Delay
sub-TLVs.
By setting the PM/Loss flag in the "OAM OAM Function Flags Sub-TLV" Sub-TLV and by
including the "MPLS MPLS OAM PM Loss Sub-TLV", Sub-TLV, one can configure the
measurement interval and loss threshold values for triggering
protection.
Delay measurements are configured by setting the PM/Delay flag in the
"OAM
OAM Function Flags Sub-TLV"; Sub-TLV; by including the "MPLS MPLS OAM PM Loss Sub-
TLV",
TLV, one can configure the measurement interval and the delay
threshold values for triggering protection.
3.1.3. Configuration of Fault Management Signals
To configure Fault Management Signals signals and their refresh time, the FMS
flag in the "OAM OAM Function Flags Sub-TLV" Sub-TLV MUST be set and the "MPLS MPLS OAM
FMS Sub-TLV" Sub-TLV included. When configuring Fault Management
Signals, signals, an
implementation can enable the default configuration by setting the
FMS flag in the "OAM OAM Function Flags Sub-TLV". Sub-TLV. In order to modify the
default configuration, the "MPLS MPLS OAM FMS Sub-TLV" Sub-TLV MUST be included.
If an intermediate point is intended to originate fault management
signal messages, this means that such an intermediate point is
associated with a server MEP through a co-located MPLS-TP client/
server adaptation function, and the "Fault Management subscription"
flag in the "MPLS MPLS OAM FMS Sub-TLV" Sub-TLV has been set as an indication of the
request to create the association at each intermediate node of the
client LSP. The corresponding server MEP needs to be configured by
its own RSVP-TE session (or, alternatively, via an NMS or LSP Ping).
3.2. MPLS OAM Configuration Sub-TLV
The "OAM OAM Configuration TLV", TLV, defined in [RFC7260], specifies the OAM
functions that are used for the LSP. This document extends the "OAM OAM
Configuration TLV" TLV by defining a new OAM Type: "MPLS OAM" (3). The
"MPLS OAM"
MPLS OAM type is set to request the establishment of OAM functions
for MPLS-TP LSPs. The specific OAM functions are specified in the
"OAM
OAM Function Flags Sub-TLV" Sub-TLV as depicted in [RFC7260].
When an egress LSR receives an "OAM OAM Configuration TLV" TLV indicating the
MPLS OAM type, the LSR will first process any present "OAM OAM Function
Flags Sub-TLV", Sub-TLV, and then it MUST process technology-specific
configuration TLVs. This document defines a sub-TLV, the "MPLS MPLS OAM
Configuration Sub-TLV", Sub-TLV, which is carried in the "OAM OAM Configuration
TLV". TLV.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MPLS OAM Conf. Sub-TLV (33) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
~ sub-TLVs ~
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 1: MPLS OAM Configuration Sub-TLV Format
Type: 33, the "MPLS MPLS OAM Configuration Sub-TLV". Sub-TLV.
Length: Indicates the total length in octets, including sub-TLVs as
well as the Type and Length fields.
The following MPLS-OAM-specific sub-TLVs MAY be included in the "MPLS MPLS
OAM Configuration Sub-TLV": Sub-TLV:
o "BFD BFD Configuration Sub-TLV" Sub-TLV MUST be included if either the CC, the
CV, or both OAM Function flags are being set in the OAM Function
Flags Sub-TLV [RFC7260]. This sub-TLV carries additional sub-
TLVs; failure to include the correct sub-TLVs MUST result in an
error being generated: "OAM Problem/Configuration Error". The
sub-TLVs are:
* "BFD BFD Identifiers Sub-TLV" Sub-TLV MUST always be included.
* "Timer Timer Negotiation Parameters Sub-TLV" Sub-TLV MUST be included if the N
flag is not set.
* "BFD BFD Authentication Sub-TLV" Sub-TLV MAY be included if the I flag is
set.
o "Performance Performance Monitoring Sub-TLV", Sub-TLV, which MUST be included if any of
the PM/Delay, PM/Loss, or PM/Throughput flags are set in the "OAM OAM
Function Flag Sub-TLV" Sub-TLV [RFC7260]. This sub-TLV MAY carry
additional sub-TLVs:
* "MPLS MPLS OAM PM Loss Sub-TLV" Sub-TLV MAY be included if the PM/Loss OAM
Function flag is set. If the "MPLS MPLS OAM PM Loss Sub-TLV" Sub-TLV is not
included, default configuration values are used. The same sub-
TLV MAY also be included in case the PM/Throughput OAM Function
flag is set and there is the need to specify measurement
intervals different from the default ones. Since throughput
measurements use the same tool as loss measurements, the same
TLV is used.
* "MPLS MPLS OAM PM Delay Sub-TLV" Sub-TLV MAY be included if the PM/Delay OAM
Function flag is set. If the "MPLS MPLS OAM PM Delay Sub-TLV" Sub-TLV is not
included, default configuration values are used.
o "MPLS MPLS OAM FMS Sub-TLV" Sub-TLV MAY be included if the FMS OAM Function flag
is set. If the "MPLS MPLS OAM FMS Sub-TLV" Sub-TLV is not included, default
configuration values are used.
The following are some additional rules of processing the "MPLS MPLS OAM
Configuration Sub-TLV": Sub-TLV:
o The "MPLS MPLS OAM Configuration Sub-TLV" Sub-TLV MAY be empty, i.e., have no
Value. If so, then its Length MUST be 8. Then, all OAM functions
that have their corresponding flags set in the "OAM OAM Function Flags
Sub-TLV"
Sub-TLV MUST be assigned their default values or left disabled.
o A sub-TLV that doesn't have a corresponding flag set MUST be
silently ignored.
o If multiple copies of a sub-TLV are present, then only the first
sub-TLV MUST be used and the remaining sub-TLVs MUST be silently
ignored.
However, not all the values can be derived from the standard RSVP-TE
objects, in particular the locally assigned Tunnel ID at the egress
cannot be derived by the ingress node. Therefore, the full LSP MEP-
ID used by the ingress has to be carried in the "BFD BFD Identifiers Sub-
TLV"
TLV in the Path message and the egress LSP MEP-ID in the same way in
the Resv message.
3.2.1. CV Flag Rules of Use
If the CV flag is set in the OAM Function Flags Sub-TLV [RFC7260],
then the CC flag MUST be set as well because performing Connectivity
Verification implies performing Continuity Check as well. The format
of an MPLS-TP CV/CC message is shown in [RFC6428]. In order to
perform Connectivity Verification, the CV/CC message MUST contain the
"LSP MEP-ID" in addition to the BFD Control packet information. The
"LSP MEP-ID" contains four identifiers:
MPLS-TP Global_ID
MPLS-TP Node Identifier
Tunnel_Num
LSP_Num
These values need to be correctly set by both ingress and egress when
transmitting a CV packet, and both ingress and egress need to know
what to expect when receiving a CV packet. Most of these values can
be derived from the Path and Resv messages [RFC3473], which use a
5-tuple to uniquely identify an LSP within an operator's network.
This tuple is composed of a Tunnel Sender Address, Tunnel Endpoint
Address, Tunnel_ID, Extended Tunnel ID, and (GMPLS) LSP_ID.
3.3. BFD Configuration Sub-TLV
The "BFD BFD Configuration Sub-TLV" Sub-TLV (depicted below) is defined for BFD-
OAM-specific configuration parameters. The "BFD BFD Configuration Sub-
TLV" Sub-TLV
is carried as a sub-TLV of the "MPLS MPLS OAM Configuration Sub-TLV". Sub-TLV.
This 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 Conf. Type (1) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Vers.|N|S|I|G|U|B| Reserved (set to all 0s) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
~ sub-TLVs ~
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2: BFD Configuration Sub-TLV Format
Type: 1, the "BFD BFD Configuration Sub-TLV". Sub-TLV.
Length: Indicates the total length in octets, including sub-TLVs as
well as the Type and Length fields.
Version: Identifies the BFD protocol version. If the egress LSR does
not support the version, an error MUST be generated: "OAM Problem/
Unsupported BFD Version".
BFD Negotiation (N): If set timer negotiation/re-negotiation via BFD
Control Messages messages is enabled, when cleared it is disabled.
Symmetric Session (S): If set, the BFD session MUST use symmetric
timing values.
Integrity (I): If set, BFD Authentication MUST be enabled. If the
"BFD
BFD Configuration Sub-TLV" Sub-TLV does not include a "BFD BFD Authentication
Sub-TLV", Sub-
TLV, the authentication MUST use Keyed SHA1 with an empty pre-
shared pre-shared
key (all 0s). If the egress LSR does not support BFD Authentication,
an error MUST be generated: "OAM Problem/BFD Authentication
unsupported".
Encapsulation Capability (G): If set, it shows the capability of
encapsulating BFD messages into The G-Ach channel. If both the G bit
and U bit are set, configuration gives precedence to the G bit. If
the egress LSR does not support any of the ingress LSR Encapsulation
Capabilities, an error MUST be generated: "OAM Problem/Unsupported
BFD Encapsulation format".
Encapsulation Capability (U): If set, it shows the capability of
encapsulating BFD messages into UDP packets. If both the G bit and U
bit are set, configuration gives precedence to the G bit. If the
egress LSR does not support any of the ingress LSR Encapsulation
Capabilities, an error MUST be generated: "OAM Problem/Unsupported
BFD Encapsulation Format".
Bidirectional (B): If set, it configures BFD in the Bidirectional
mode. If it is not set, it configures BFD in unidirectional mode.
In the second case, the source node does not expect any Discriminator
values back from the destination node.
Reserved: Reserved for future specifications; set to 0 on
transmission and ignored when received.
The "BFD BFD Configuration Sub-TLV" Sub-TLV MUST include the following sub-TLVs in
the Path message:
o "BFD BFD Identifiers Sub-TLV"; Sub-TLV; and
o "Negotiation Negotiation Timer Parameters Sub-TLV" Sub-TLV if the N flag is cleared.
The "BFD BFD Configuration Sub-TLV" Sub-TLV MUST include the following sub-TLVs in
the Resv message:
o "BFD BFD Identifiers Sub-TLV"; Sub-TLV; and
o "Negotiation Negotiation Timer Parameters Sub-TLV" Sub-TLV if:
* the N and S flags are cleared; or if
* the N flag is cleared and the S flag is set and the
"Negotiation Negotiation
Timer Parameters Sub-TLV" Sub-TLV received by the egress contains
unsupported values. In this case, an updated
"Negotiation Negotiation Timer
Parameters Sub-TLV" Sub-TLV containing values supported by the egress
LSR MUST be returned to the ingress.
3.3.1. BFD Identifiers Sub-TLV
The "BFD BFD Identifiers Sub-TLV" Sub-TLV is carried as a sub-TLV of the "BFD BFD
Configuration Sub-TLV" Sub-TLV and 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| BFD Identfiers Type (1) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Local Discriminator |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MPLS-TP Global_ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MPLS-TP Node Identifier |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Tunnel_Num | LSP_Num |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 3: BFD Identifiers Sub-TLV Format
Type: 1, the "BFD BFD Identifiers Sub-TLV". Sub-TLV.
Length: Indicates the TLV total length in octets, including the Type
and Length fields (20).
Local Discriminator: A unique, non-zero discriminator value generated
by the transmitting system and referring to itself; it is used to de-
multiplex multiple BFD sessions between the same pair of systems as
defined in [RFC5880].
MPLS-TP Global_ID, Node Identifier, Tunnel_Num, and LSP_Num: All set
as defined in [RFC6370].
3.3.2. Negotiation Timer Parameters Sub-TLV
The "Negotiation Negotiation Timer Parameters Sub-TLV" Sub-TLV is carried as a sub-TLV of
the "BFD BFD Configuration Sub-TLV" Sub-TLV and 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Nego. Timer Type (2) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Acceptable Min. Asynchronous TX interval |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Acceptable Min. Asynchronous RX interval |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Required Echo TX Interval |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 4: Negotiation Timer Parameters Sub-TLV Format
Type: 2, the "Negotiation Negotiation Timer Parameters Sub-TLV". Sub-TLV.
Length: Indicates the TLV total length in octets, including Type and
Length fields (16).
Acceptable Min. Asynchronous TX interval: If the S flag is set in the
"BFD
BFD Configuration Sub-TLV", Sub-TLV, it expresses the desired time interval (in
microseconds) at which the ingress LER intends to both transmit and
receive BFD periodic control packets. If the egress LSR cannot
support the value, it SHOULD reply with a supported interval.
If the S flag is cleared in the "BFD BFD Configuration Sub-TLV", Sub-TLV, this field
expresses the desired time interval (in microseconds) at which the
ingress LSR intends to transmit BFD periodic control packets.
Acceptable Min. Asynchronous RX interval: If the S flag is set in the
"BFD
BFD Configuration Sub-TLV", Sub-TLV, this field MUST be set equal to
"Acceptable Min. Asynchronous TX interval" on transmit and MUST be
ignored on receipt since it has no additional meaning with respect to
the one described for "Acceptable Min. Asynchronous TX interval".
If the S flag is cleared in the "BFD BFD Configuration Sub-TLV", Sub-TLV, it
expresses the minimum time interval (in microseconds) at which the
ingress/egress LSRs can receive periodic BFD control Control packets. If
this value is greater than the "Acceptable Min. Asynchronous TX
interval" received from the ingress/egress LSR, the receiving LSR
MUST adopt the interval expressed in the "Acceptable Min.
Asynchronous RX interval".
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
Section 6.8.9 of [RFC5880]. 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 LSR node cannot
support this value, it SHOULD reply with a supported value (which may
be zero if Echo is not supported).
3.3.3. BFD Authentication Sub-TLV
The "BFD BFD Authentication Sub-TLV" Sub-TLV is carried as a sub-TLV of the "BFD BFD
Configuration Sub-TLV" Sub-TLV and 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| BFD Auth. Type (3) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Auth Type | Auth Key ID | Reserved (0s) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 5: BFD Authentication Sub-TLV Format
Type: 3, the "BFD BFD Authentication Sub-TLV". Sub-TLV.
Length: Indicates the TLV total length in octets, including Type and
Length fields (8).
Auth Type: Indicates which type of authentication to use. The same
values are used as are defined in Section 4.1 of [RFC5880]. If the
egress LSR does not support this type, an "OAM Problem/Unsupported
BFD Authentication Type" error MUST be generated.
Auth Key ID: Indicates which authentication key or password
(depending on Auth Type) should be used. How the key exchange is
performed is out of scope of this document. If the egress LSR does
not support this Auth Key ID, an "OAM Problem/Mismatch of BFD
Authentication Key ID" error MUST be generated.
Reserved: Reserved for future specifications; set to 0 on
transmission and ignored when received.
3.3.4. Traffic Class Sub-TLV
The "Traffic Traffic Class Sub-TLV" Sub-TLV is carried as a sub-TLV of the "BFD BFD
Configuration Sub-TLV" Sub-TLV or "Fault Fault Management Signal Sub-TLV" Sub-TLV
(Section 3.5) and is depicted in Figure 1. 6.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Traffic Class Sub-Type (4) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| TC | Reserved (set to all 0s) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 1: 6: Traffic Class Sub-TLV format Format
Type: 3, 4, the "Traffic Traffic Class Sub-TLV". Sub-TLV.
Length: Indicates the length of the Value field in octets (4).
Traffic Class (TC): Identifies the TC [RFC5462] for periodic
continuity monitoring messages or packets with fault management
information.
If the "Traffic Traffic Class Sub-TLV" Sub-TLV is present, then the value of the TC
field MUST be used as the value of the TC field of an MPLS label
stack entry. If the "Traffic Traffic Class Sub-TLV" Sub-TLV is absent from "BFD BFD
Configuration Sub-TLV" Sub-TLV or "Fault Fault Management Signal Sub-TLV", Sub-TLV, then
selection of the TC value is a local decision.
3.4. Performance Monitoring Sub-TLV
If the "OAM OAM Function Flags Sub-TLV" Sub-TLV has either the PM/Loss, PM/Delay,
or PM/Throughput flag set, the "Performance Performance Monitoring Sub-TLV" Sub-TLV MUST be
present in the "MPLS MPLS OAM Configuration Sub-TLV". Sub-TLV. Failure to include
the correct sub-TLVs MUST result in an "OAM Problem/
Configuration Problem/Configuration
Error" message being generated.
The "Performance Performance Monitoring Sub-TLV" Sub-TLV provides the configuration
information mentioned in Section 7 of [RFC6374]. It includes support
for the configuration of quality thresholds and, as described in
[RFC6374], "the crossing of which will trigger warnings or alarms,
and result reporting and exception notification will be integrated
into the system-wide network management and reporting framework."
In case the values need to be different than the default ones, the
"Performance
Performance Monitoring Sub-TLV" Sub-TLV includes the following sub-TLVs:
o "MPLS MPLS OAM PM Loss Sub-TLV" Sub-TLV if the PM/Loss and/or PM/Throughput flag
is set in the "OAM OAM Function Flags Sub-TLV"; Sub-TLV; and
o "MPLS MPLS OAM PM Delay Sub-TLV" Sub-TLV if the PM/Delay flag is set in the
"OAM OAM
Function Flags Sub-TLV". Sub-TLV.
The "Performance Performance Monitoring Sub-TLV" Sub-TLV depicted below is carried as a
sub-TLV of the "MPLS MPLS OAM Configuration Sub-TLV". Sub-TLV.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Perf. Monitoring Type (2) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|D|L|J|Y|K|C| Reserved (set to all 0s) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
~ sub-TLVs ~
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 7: Performance Monitoring Sub-TLV Format
Type: 2, the "Performance Performance Monitoring Sub-TLV". Sub-TLV.
Length: Indicates the TLV total length in octets, including sub-TLVs
as well as Type and Length fields.
Configuration Flags (for the specific function description please
refer to [RFC6374]):
o D: Delay inferred/direct (0=INFERRED, 1=DIRECT). If the egress
LSR does not support the specified mode, an "OAM Problem/
Unsupported Delay Mode" error MUST be generated.
o L: Loss inferred/direct (0=INFERRED, 1=DIRECT). If the egress LSR
does not support the specified mode, an "OAM Problem/Unsupported
Loss Mode" error MUST be generated.
o J: Delay variation/jitter (1=ACTIVE, 0=NOT ACTIVE). If the egress
LSR does not support Delay variation measurements and the J flag
is set, an "OAM Problem/Delay variation unsupported" error MUST be
generated.
o Y: Dyadic (1=ACTIVE, 0=NOT ACTIVE). If the egress LSR does not
support Dyadic mode and the Y flag is set, an "OAM Problem/Dyadic
mode unsupported" error MUST be generated.
o K: Loopback (1=ACTIVE, 0=NOT ACTIVE). If the egress LSR does not
support Loopback mode and the K flag is set, an "OAM Problem/
Loopback mode unsupported" error MUST be generated.
o C: Combined (1=ACTIVE, 0=NOT ACTIVE). If the egress LSR does not
support Combined mode and the C flag is set, an "OAM Problem/
Combined mode unsupported" error MUST be generated.
Reserved: Reserved for future specifications; set to 0 on
transmission and ignored when received.
3.4.1. MPLS OAM PM Loss Sub-TLV
The "MPLS MPLS OAM PM Loss Sub-TLV" Sub-TLV depicted below is carried as a sub-TLV
of the "Performance Performance Monitoring Sub-TLV". Sub-TLV.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| PM Loss Type (1) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| OTF |T|B| Reserved (set to all 0s) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Measurement Interval |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Test Interval |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Loss Threshold |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 8: MPLS OAM PM Loss Sub-TLV Format
Type: 1, the "MPLS MPLS OAM PM Loss Sub-TLV". Sub-TLV.
Length: Indicates the length of the parameters in octets, including
Type and Length fields (20).
Origin Timestamp Format (OTF): Origin Timestamp Format of the Origin
Timestamp field described in [RFC6374]. By default, it is set to
IEEE 1588 version 1. If the egress LSR cannot support this value, an
"OAM Problem/Unsupported Timestamp Format" error MUST be generated.
Configuration Flags (please refer to [RFC6374] for further details):
o T: Traffic-class-specific measurement indicator. Set to 1 when
the measurement operation is scoped to packets of a particular
traffic class (Differentiated Service Code Point (DSCP) value) and
zero otherwise. When set to 1, the Differentiated Services (DS)
field of the message indicates the measured traffic class. By
default, it is set to 1.
o B: Octet (byte) count. When set to 1, it indicates that the
Counter 1-4 fields represent octet counts. When set to 0, it
indicates that the Counter 1-4 fields represent packet counts. By
default, it is set to 0.
Reserved: Reserved for future specifications; set to 0 on
transmission and ignored when received.
Measurement Interval: The time interval (in milliseconds) at which
Loss Measurement query messages MUST be sent in both directions. If
the egress LSR cannot support the value, it SHOULD reply with a
supported interval. By default, it is set to 100 milliseconds as per
[RFC6375].
Test Interval: Test messages interval (in milliseconds) as described
in [RFC6374]. By default, it is set to 10 milliseconds as per
[RFC6375]. If the egress LSR cannot support the value, it SHOULD
reply with a supported interval.
Loss Threshold: The threshold value of measured lost packets per
measurement over which action(s) SHOULD be triggered.
3.4.2. MPLS OAM PM Delay Sub-TLV
The "MPLS MPLS OAM PM Delay Sub-TLV" Sub-TLV depicted below is carried as a sub-
TLV sub-TLV
of the "Performance Performance Monitoring Sub-TLV". Sub-TLV.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| PM Delay Type (2) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| OTF |T|B| Reserved (set to all 0s) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Measurement Interval |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Test Interval |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Delay Threshold |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 9: MPLS OAM PM Delay Sub-TLV Format
Type: 2, the "MPLS MPLS OAM PM Delay Sub-TLV". Sub-TLV.
Length: Indicates the length of the parameters in octets, including
Type and Length fields (20).
OTF: Origin Timestamp Format of the Origin Timestamp field described
in [RFC6374]. By default, it is set to IEEE 1588 version 1. If the
egress LSR cannot support this value, an "OAM Problem/Unsupported
Timestamp Format" error MUST be generated.
Configuration Flags (please refer to [RFC6374] for further details):
o T: Traffic-class-specific measurement indicator. Set to 1 when
the measurement operation is scoped to packets of a particular
traffic class (Differentiated Services Code Point (DSCP) value)
and zero otherwise. When set to 1, the Differentiated Service
(DS) field of the message indicates the measured traffic class.
By default, it is set to 1.
o B: Octet (byte) count. When set to 1, it indicates that the
Counter 1-4 fields represent octet counts. When set to 0, it
indicates that the Counter 1-4 fields represent packet counts. By
default, it is set to 0.
Reserved: Reserved for future specifications; set to 0 on
transmission and ignored when received.
Measurement Interval: The time interval (in milliseconds) at which
Delay Measurement query messages MUST be sent on both directions. If
the egress LSR cannot support the value, it SHOULD reply with a
supported interval. By default, it is set to 1000 milliseconds as
per [RFC6375].
Test Interval: Test messages interval (in milliseconds) as described
in [RFC6374]. By default, it is set to 10 milliseconds as per
[RFC6375]. If the egress LSR cannot support the value, it SHOULD
reply with a supported interval.
Delay Threshold: The threshold value of measured two-way delay (in
milliseconds) over which action(s) SHOULD be triggered.
3.5. MPLS OAM FMS Sub-TLV
The "MPLS MPLS OAM FMS Sub-TLV" Sub-TLV depicted below is carried as a sub-TLV of
the "MPLS MPLS OAM Configuration Sub-TLV". Sub-TLV. When both working and protection
paths are signaled, both LSPs SHOULD be signaled with identical
settings of the E flag, T flag, and the refresh timer.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MPLS OAM FMS Type (3) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|E|S|T| Reserved | Refresh Timer |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
~ Sub-TLVs ~
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 10: MPLS OAM FMS Sub-TLV Format
Type: 3, the "MPLS MPLS OAM FMS Sub-TLV". Sub-TLV.
Length: Indicates the TLV total length in octets, including Type and
Length fields (8).
FMS Signal Flags are used to enable the FMS signals at endpoint MEPs and the
server MEPs of the links over which the LSP is forwarded. In this
document, only the S flag pertains to server MEPs.
The following flags are defined:
E: Enable Alarm Indication Signal (AIS) and Lock Report (LKR)
signaling as described in [RFC6427]. The default value is 1
(enabled). If the egress MEP does not support FMS signal
generation, an "OAM Problem/Fault management signaling
unsupported" error MUST be generated.
S: Indicate to a server MEP that it should transmit AIS and LKR
signals on client LSPs. The default value is 0 (disabled). If a
server MEP, which is capable of generating FMS messages, is for
some reason unable to do so for the LSP being signaled an "OAM
Problem/Unable to create fault management association" error MUST
be generated.
T: Set timer value, enabled by the configuration of a specific
timer value. The Default value is 0 (disabled).
Remaining bits: Reserved for a future specification and set to 0.
Refresh Timer: Indicates (in seconds) the refresh timer of fault
indication messages. The value MUST be between 1 to 20 seconds as
specified for the Refresh Timer field in [RFC6427]. If the egress
LSR cannot support the value, it SHOULD reply with a supported timer
value.
The "Fault Fault Management Signals Sub-TLV" Sub-TLV MAY include the "Traffic Traffic Class
Sub-TLV"
Sub-TLV (Section 3.3.4.) If the "Traffic Traffic Class Sub-TLV" Sub-TLV is present,
the value of the TC field MUST be used as the value of the TC field
of an MPLS label stack entry for FMS messages. If the "Traffic Traffic Class
Sub-TLV"
Sub-TLV is absent, then selection of the TC value is local decision.
4. Summary of MPLS OAM Configuration Errors
In addition to error values specified in [RFC7260], this document
defines the following values for the "OAM Problem" error code:
o If an egress LSR does not support the specified BFD version, an
error MUST be generated: "OAM Problem/Unsupported BFD Version".
o If an egress LSR does not support the specified BFD Encapsulation
format, an error MUST be generated: "OAM Problem/Unsupported BFD
Encapsulation format".
o If an egress LSR does not support BFD Authentication and it is
requested, an error MUST be generated: "OAM Problem/BFD
Authentication unsupported".
o If an egress LSR does not support the specified BFD Authentication
Type, an error MUST be generated: "OAM Problem/Unsupported BFD
Authentication Type".
o If an egress LSR is not able to use the specified Authentication
Key ID, an error MUST be generated: "OAM Problem/Mismatch of BFD
Authentication Key ID".
o If an egress LSR does not support the specified Timestamp Format,
an error MUST be generated: "OAM Problem/Unsupported Timestamp
Format".
o If an egress LSR does not support the specified Delay mode, an
"OAM Problem/Unsupported Delay Mode" error MUST be generated.
o If an egress LSR does not support the specified Loss mode, an "OAM
Problem/Unsupported Loss Mode" error MUST be generated.
o If an egress LSR does not support Delay variation measurements and
it is requested, an "OAM Problem/Delay variation unsupported"
error MUST be generated.
o If an egress LSR does not support Dyadic mode and it is requested,
an "OAM Problem/Dyadic mode unsupported" error MUST be generated.
o If an egress LSR does not support Loopback mode and it is
requested, an "OAM Problem/Loopback mode unsupported" error MUST
be generated.
o If an egress LSR does not support Combined mode and it is
requested, an "OAM Problem/Combined mode unsupported" error MUST
be generated.
o If an egress LSR does not support Fault Monitoring Signals signals and it
is requested, an "OAM Problem/Fault management signaling
unsupported" error MUST be generated.
o If an intermediate server MEP supports Fault Monitoring Signals signals
but is unable to create an association when requested to do so, an
"OAM Problem/Unable to create fault management association" error
MUST be generated.
5. IANA Considerations
5.1. MPLS OAM Type
This document specifies the new "MPLS OAM" MPLS OAM type. IANA has allocated a
new type (3) from the "OAM Types" space of the "RSVP-TE OAM
Configuration Registry".
+------+-------------+-----------+
| Type | Description | Reference |
+------+-------------+-----------+
| 3 | MPLS OAM | [RFC7487] |
+------+-------------+-----------+
Table 1: MPLS OAM Type
5.2. MPLS OAM Configuration Sub-TLV
This document specifies the "MPLS MPLS OAM Configuration Sub-TLV". Sub-TLV. IANA has
allocated a new type (33) from the "OAM Sub-TLV" OAM Sub-TLV space of the "RSVP-TE
OAM Configuration Registry".
+------+--------------------------------+-----------+
| Type | Description | Reference |
+------+--------------------------------+-----------+
| 33 | MPLS OAM Configuration Sub-TLV | [RFC7487] |
+------+--------------------------------+-----------+
Table 2: MPLS OAM Configuration Sub-TLV Type
5.3. MPLS OAM Configuration Sub-TLV Types
IANA has created an "MPLS OAM Configuration Sub-TLV Types" sub-
registry in the "RSVP-TE OAM Configuration Registry" for the sub-TLVs
carried in the "MPLS MPLS OAM Configuration Sub-TLV". Sub-TLV. Values from this new
sub-registry are to be allocated through IETF Review except for the
"Reserved for Experimental Use" range. This document defines the
following types:
+-------------+--------------------------------+-----------+
| Type | Description | Reference |
+-------------+--------------------------------+-----------+
| 0 | Reserved | [RFC7487] |
| 1 | BFD Configuration Sub-TLV | [RFC7487] |
| 2 | Performance Monitoring Sub-TLV | [RFC7487] |
| 3 | MPLS OAM FMS Sub-TLV | [RFC7487] |
| 4-65532 | Unassigned | |
| 65533-65534 | Reserved for Experimental Use | [RFC7487] |
| 65535 | Reserved | [RFC7487] |
+-------------+--------------------------------+-----------+
Table 3: MPLS OAM Configuration Sub-TLV Types
5.4. BFD Configuration Sub-TLV Types
IANA has created a "BFD Configuration Sub-TLV Types" sub-registry in
the "RSVP-TE OAM Configuration Registry" for the sub-TLV types
carried in the "BFD BFD Configuration Sub-TLV". Sub-TLV. Values from this new
sub-registry sub-
registry are to be allocated through IETF Review except for the
"Reserved for Experimental Use" range. This document defines the
following types:
+-------------+--------------------------------------+-----------+
| Type | Description | Reference |
+-------------+--------------------------------------+-----------+
| 0 | Reserved | [RFC7487] |
| 1 | BFD Identifiers Sub-TLV | [RFC7487] |
| 2 | Negotiation Timer Parameters Sub-TLV | [RFC7487] |
| 3 | BFD Authentication Sub-TLV | [RFC7487] |
| 4 | Traffic Class Sub-TLV | [RFC7487] |
| 5-65532 | Unassigned | |
| 65533-65534 | Reserved for Experimental Use | [RFC7487] |
| 65535 | Reserved | [RFC7487] |
+-------------+--------------------------------------+-----------+
Table 4: BFD Configuration Sub-TLV Types
5.5. Performance Monitoring Sub-TLV Types
IANA has created a "Performance Monitoring Sub-TLV Type" sub-registry
in the "RSVP-TE OAM Configuration Registry" for the sub-TLV types
carried in the "Performance Performance Monitoring Sub-TLV". Sub-TLV. Values from this new
sub-registry are to be allocated through IETF Review except for the
"Reserved for Experimental Use" range. This document defines the
following types:
+-------------+-------------------------------+-----------+
| Type | Description | Reference |
+-------------+-------------------------------+-----------+
| 0 | Reserved | [RFC7487] |
| 1 | MPLS OAM PM Loss Sub-TLV | [RFC7487] |
| 2 | MPLS OAM PM Delay Sub-TLV | [RFC7487] |
| 3-65532 | Unassigned | |
| 65533-65534 | Reserved for Experimental Use | [RFC7487] |
| 65535 | Reserved | [RFC7487] |
+-------------+-------------------------------+-----------+
Table 5: Performance Monitoring Sub-TLV Types
5.6. New RSVP-TE Error Codes
The following values have been assigned under the "OAM Problem" error
code [RFC7260] by IETF Review process:
+------------------+------------------------------------+-----------+
| Error Value Sub- | Description | Reference |
| Codes | | |
+------------------+------------------------------------+-----------+
| 13 | Unsupported BFD Version | [RFC7487] |
| 14 | Unsupported BFD Encapsulation | [RFC7487] |
| | format | |
| 15 | Unsupported BFD Authentication | [RFC7487] |
| | Type | |
| 16 | Mismatch of BFD Authentication Key | [RFC7487] |
| | ID | |
| 17 | Unsupported Timestamp Format | [RFC7487] |
| 18 | Unsupported Delay Mode | [RFC7487] |
| 19 | Unsupported Loss Mode | [RFC7487] |
| 20 | Delay variation unsupported | [RFC7487] |
| 21 | Dyadic mode unsupported | [RFC7487] |
| 22 | Loopback mode unsupported | [RFC7487] |
| 23 | Combined mode unsupported | [RFC7487] |
| 24 | Fault management signaling | [RFC7487] |
| | unsupported | |
| 25 | Unable to create fault management | [RFC7487] |
| | association | |
+------------------+------------------------------------+-----------+
Table 6: MPLS OAM Configuration Error Codes
The "Sub-Codes - 40 OAM Problem" sub-registry is located in the
"Error Codes and Globally-Defined Error Value Sub-Codes" registry.
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 were to request
high frequency liveliness monitoring of a large number of LSPs,
targeting a single network element as discussed in [RFC7260] and
[RFC6060].
Additional discussion of security for MPLS and GMPLS protocols can be
found in [RFC5920].
7. References
7.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997,
<http://www.rfc-editor.org/info/rfc2119>.
[RFC3473] Berger, L., Ed., "Generalized Multi-Protocol Label
Switching (GMPLS) Signaling Resource ReserVation Protocol-
Traffic Engineering (RSVP-TE) Extensions", RFC 3473,
January 2003, <http://www.rfc-editor.org/info/rfc3473>.
[RFC5654] Niven-Jenkins, B., Ed., Brungard, D., Ed., Betts, M., Ed.,
Sprecher, N., and S. Ueno, "Requirements of an MPLS
Transport Profile", RFC 5654, September 2009,
<http://www.rfc-editor.org/info/rfc5654>.
[RFC5860] Vigoureux, M., Ed., Ward, D., Ed., and M. Betts, Ed.,
"Requirements for Operations, Administration, and
Maintenance (OAM) in MPLS Transport Networks", RFC 5860,
May 2010, <http://www.rfc-editor.org/info/rfc5860>.
[RFC5880] Katz, D. and D. Ward, "Bidirectional Forwarding Detection
(BFD)", RFC 5880, June 2010,
<http://www.rfc-editor.org/info/rfc5880>.
[RFC5884] Aggarwal, R., Kompella, K., Nadeau, T., and G. Swallow,
"Bidirectional Forwarding Detection (BFD) for MPLS Label
Switched Paths (LSPs)", RFC 5884, June 2010,
<http://www.rfc-editor.org/info/rfc5884>.
[RFC6060] Fedyk, D., Shah, H., Bitar, N., and A. Takacs,
"Generalized Multiprotocol Label Switching (GMPLS) Control
of Ethernet Provider Backbone Traffic Engineering (PBB-
TE)", RFC 6060, March 2011,
<http://www.rfc-editor.org/info/rfc6060>.
[RFC6370] Bocci, M., Swallow, G., and E. Gray, "MPLS Transport
Profile (MPLS-TP) Identifiers", RFC 6370, September 2011,
<http://www.rfc-editor.org/info/rfc6370>.
[RFC6374] Frost, D. and S. Bryant, "Packet Loss and Delay
Measurement for MPLS Networks", RFC 6374, September 2011,
<http://www.rfc-editor.org/info/rfc6374>.
[RFC6427] Swallow, G., Ed., Fulignoli, A., Ed., Vigoureux, M., Ed.,
Boutros, S., and D. Ward, "MPLS Fault Management
Operations, Administration, and Maintenance (OAM)", RFC
6427, November 2011,
<http://www.rfc-editor.org/info/rfc6427>.
[RFC6428] Allan, D., Ed., Swallow Ed., G., and J. Drake Ed.,
"Proactive Connectivity Verification, Continuity Check,
and Remote Defect Indication for the MPLS Transport
Profile", RFC 6428, November 2011,
<http://www.rfc-editor.org/info/rfc6428>.
[RFC7260] Takacs, A., Fedyk, D., and J. He, "GMPLS RSVP-TE
Extensions for Operations, Administration, and Maintenance
(OAM) Configuration", RFC 7260, June 2014,
<http://www.rfc-editor.org/info/rfc7260>.
7.2. Informative References
[LSP-PING-CONF]
Bellagamba, E., Mirsky, G., Andersson, L., Skoldstrom, P.,
Ward, D., and J. Drake, "Configuration of Proactive
Operations, Administration, and Maintenance (OAM)
Functions for MPLS-based Transport Networks using LSP
Ping", Work in Progress, draft-ietf-mpls-lsp-ping-mpls-tp-
oam-conf-09, January 2015.
[RFC5462] Andersson, L. and R. Asati, "Multiprotocol Label Switching
(MPLS) Label Stack Entry: "EXP" Field Renamed to "Traffic
Class" Field", RFC 5462, February 2009,
<http://www.rfc-editor.org/info/rfc5462>.
[RFC5920] Fang, L., Ed., "Security Framework for MPLS and GMPLS
Networks", RFC 5920, July 2010,
<http://www.rfc-editor.org/info/rfc5920>.
[RFC6371] Busi, I., Ed. and D. Allan, Ed., "Operations,
Administration, and Maintenance Framework for MPLS-Based
Transport Networks", RFC 6371, September 2011,
<http://www.rfc-editor.org/info/rfc6371>.
[RFC6375] Frost, D., Ed. and S. Bryant, Ed., "A Packet Loss and
Delay Measurement Profile for MPLS-Based Transport
Networks", RFC 6375, September 2011,
<http://www.rfc-editor.org/info/rfc6375>.
Acknowledgements
The authors would like to thank David Allan, Lou Berger, Annamaria
Fulignoli, Eric Gray, Andras Kern, David Jocha, and David Sinicrope
for their useful comments.
Contributors
This document is the result of a large team of authors and
contributors. The following is a list of the contributors:
John Drake
Benoit Tremblay
Authors' Addresses
Elisa Bellagamba
Ericsson
EMail: elisa.bellagamba@ericsson.com
Attila Takacs
Ericsson
EMail: attila.takacs@ericsson.com
Gregory Mirsky
Ericsson
EMail: Gregory.Mirsky@ericsson.com
Loa Andersson
Huawei Technologies
EMail: loa@mail01.huawei.com
Pontus Skoldstrom
Acreo AB
Electrum 236
Kista 164 40
Sweden
Phone: +46 70 7957731
EMail: pontus.skoldstrom@acreo.se
Dave Ward
Cisco
EMail: dward@cisco.com