Network Working Group A. Takacs
Internet-Draft B. Gero
Intended status: Standards Track Ericsson
Expires: September 10, 2009 D. Fedyk
D. Mohan
Nortel
H. Long
Huawei
March 9, 2009
GMPLS RSVP-TE Extensions for Ethernet OAM Configuration
draft-ietf-ccamp-rsvp-te-eth-oam-ext-01
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Abstract
The GMPLS controlled Ethernet Label Switching (GELS) work is
extending GMPLS RSVP-TE to support the establishment of Ethernet
LSPs. IEEE Ethernet Connectivity Fault Management (CFM) specifies an
adjunct OAM flow to check connectivity in Ethernet networks. CFM can
be also used with Ethernet LSPs for fault detection and triggering
recovery mechanisms. The ITU-T Y.1731 specification builds on CFM
and specifies additional OAM mechanisms, including Performance
Monitoring, for Ethernet networks. This document specifies
extensions of GMPLS RSVP-TE to support the setup of the associated
Ethernet OAM (CFM and Y.1731) entities adding a technology specific
TLV to [OAM-CONF-FWK].
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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
Table of Contents
1. Background . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2. Overview of Ethernet OAM operation . . . . . . . . . . . . . . 6
3. GMPLS RSVP-TE Extensions . . . . . . . . . . . . . . . . . . . 8
3.1. Operation overview . . . . . . . . . . . . . . . . . . . . 8
3.2. OAM Configuration TLV . . . . . . . . . . . . . . . . . . 10
3.3. Ethernet OAM Configuration TLV . . . . . . . . . . . . . . 10
3.3.1. MD Name Sub-TLV . . . . . . . . . . . . . . . . . . . 11
3.3.2. Short MA Name Sub-TLV . . . . . . . . . . . . . . . . 12
3.3.3. MEP ID Sub-TLV . . . . . . . . . . . . . . . . . . . . 13
3.3.4. Continuity Check (CC) Sub-TLV . . . . . . . . . . . . 13
3.4. Pro-active Performance Monitoring . . . . . . . . . . . . 14
3.5. Ethernet OAM configuration errors . . . . . . . . . . . . 14
4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 16
5. Security Considerations . . . . . . . . . . . . . . . . . . . 17
6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 18
7. References . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 20
Intellectual Property and Copyright Statements . . . . . . . . . . 21
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1. Background
Provider Backbone Bridging - Traffic Engineering (PBB-TE)
[IEEE-PBBTE] decouples the Ethernet data and control planes by
explicitly supporting external control/management mechanisms to
configure static filtering entries in bridges and create explicitly
routed Ethernet connections. In addition PBB-TE defines mechanisms
for 1:1 protection switching of bidirectional Ethernet connections.
Ethernet Connectivity Fault Management (CFM) defines an adjunct
connectivity monitoring OAM flow to check the liveliness of Ethernet
networks [IEEE-CFM]. With PBB-TE Ethernet networks will support
explicitly-routed Ethernet connections. CFM can be used to track the
liveliness of PBB-TE and point-to-point VLAN connections and detect
data plane failures.
In IETF the GMPLS controlled Ethernet Label Switching (GELS)
[GELS-Framework] work is extending the GMPLS control plane to support
the establishment of PBB-TE and point-to-point VLAN data plane
connections. We refer to GMPLS established Ethernet connections as
Ethernet LSPs. GELS enables the application of MPLS-TE and GMPLS
provisioning and recovery features in Ethernet networks.
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2. Overview of Ethernet OAM operation
For the purposes of this document, we only discuss Ethernet OAM
[IEEE-CFM] aspects that are relevant for the connectivity monitoring
of PBB-TE and point-to-point VLAN connections.
PBB-TE [IEEE-PBBTE] defines point-to-point Ethernet Switched Paths
(ESPs) as a provisioned traffic engineered unidirectional
connectivity, identified by the 3-tuple [ESP-MAC DA, ESP-MAC SA, ESP-
VID] where the ESP-MAC DA is the destination address of the ESP, the
ESP-MAC SA is the source address of the ESP, and the ESP-VID is a
VLAN identifier allocated for explicitly routed connections. To form
a bidirectional PBB-TE connection two co-routed point-to-point ESPs
are combined. The combined ESPs must have the same ESP-MAC addresses
but may have different ESP-VIDs.
Note that although it would be possible to use GMPLS to setup a
single unidirectional ESP, the Ethernet OAM mechanisms are only full
functional when bidirectional connections are established with co-
routed ESPs. Hence, we focus on bidirectional point-to-point PBB-TE
connections.
At both ends of the bidirectional point-to-point PBB-TE connection
one Maintenance Endpoint (MEP) is configured. The MEPs monitoring a
PBB-TE connection must be configured with the same Maintenance Domain
Level (MD Level) and Maintenance Association Identifier (MAID). Each
MEP has a unique identifier, the MEP ID. Besides these identifiers a
MEP monitoring a PBB-TE connection must be provisioned with the
3-tuples [ESP-MAC DA, ESP-MAC SA, ESP-VID] of the two ESPs.
In the case of point-to-point VLAN connections, the connection is
identified with a single VLAN forwarding traffic in both directions
or with two VLANs each forwarding traffic in a single direction.
Hence instead of the 3-tuples of the PBB-TE case MEPs must be
provisioned with the proper VLAN information, otherwise the same MD
Level, MAID, MEP ID configuration is required in this case as well.
MEPs exchange Connectivity Check Messages (CCMs) periodically with
fixed intervals. Eight distinct intervals are defined in [IEEE-CFM]:
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+---+--------------------+----------------+
| # | CCM Interval (CCI) | 3 bit encoding |
+---+--------------------+----------------+
| 0 | Reserved | 000 |
| | | |
| 1 | 3 1/3 ms | 001 |
| | | |
| 2 | 10 ms | 010 |
| | | |
| 3 | 100 ms | 011 |
| | | |
| 4 | 1 s | 100 |
| | | |
| 5 | 10 s | 101 |
| | | |
| 6 | 1 min | 110 |
| | | |
| 7 | 10 min | 111 |
+---+--------------------+----------------+
Table 1: CCM Interval encoding
If 3 consecutive CCM messages are not received by one of the MEPs it
declares a connectivity failure and signals the failure in subsequent
CCM messages, by setting the Remote Defect Indicator (RDI) bit, to
the remote MEP. If a MEP receives a CCM message with RDI set it
immediately declares failure. The detection of a failure may trigger
protection switching mechanisms or may be signaled to a management
system. However, what happens once a failure is detected is out of
the scope of this document.
At each transit node Maintenance Intermediate Points (MIPs) can be
established to help failure localization by supporting link trace and
loop back functions. MIPs need to be provisioned with a subset of
MEP identification parameters described above.
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3. GMPLS RSVP-TE Extensions
3.1. Operation overview
To simplify the configuration of connectivity monitoring, when an
Ethernet LSP is signaled the associated MEPs should be automatically
established. To monitor an Ethernet LSP a set of parameters must be
provided to setup a Maintenance Association and related MEPs.
Optionally, MIPs may be created at the transit nodes of the Ethernet
LSP. The LSP Attributes Flags: "OAM MEP entities desired" and "OAM
MIP entities desired", described in [OAM-CONF-FWK] are used to signal
that the respective OAM entities must be established. Subsequently,
an OAM Configuration TLV is added to the LSP_ATTRIBUTES Object
specifying that Ethernet OAM is to be setup for the LSP. The below
detailed Ethernet OAM specific information is carried in a new sub-
TLV.
o A unique MAID must be allocated for the PBB-TE connection and both
MEPs must be configured with the same information. The MAID
consists of an optional Maintenance Domain Name (MD Name) and a
mandatory Short Maintenance Association Name (Short MA Name).
Various formatting rules for these names have been defined by
[IEEE-CFM]. Since these information is also carried in all CCM
messages, the combined length of the Names is limited to 44 bytes.
How these parameters are determined is out of scope of this
document.
o Each MEP must be provisioned with a MEP ID. The MEP ID uniquely
identifies a given MEP within a Maintenance Association. That is,
the combination of MAID and MEP ID must uniquely identify a MEP.
How the value of the MEP ID is determined is out of scope of this
document.
o The Maintenance Domain Level (MD Level) allows hierarchical
separation of monitoring entities. [IEEE-CFM] allows
differentiation of 8 levels. How the value of the MD Level is
determined is out of scope of this document. Note that most
probably for all Ethernet LSPs a single (default) MD Level will be
used in a network domain.
o The desired CCM Interval must be specified by the management
system based on service requirements or operator policy. The same
CCM Interval must be set in each of the MEPs monitoring a given
Ethernet LSP. How the value of the CCM Interval is determined is
out of scope of this document.
o The desired CCM priority to be set by MEPs for the CCM frames can
be specified. The same CCM priority must be set in each of the
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MEPs monitoring a given Ethernet LSP. How CCM priority is
determined is out of scope of this document. Note that the
highest priority is used as the default CCM priority.
o MEPs must be aware of their own and the reachability parameters of
the remote MEP. In the case of bidirectional point-to-point
PBB-TE connections this requires that the 3-tuples [ESP-MAC A,
ESP-MAC B, ESP-VID1] and [ESP-MAC B, ESP-MAC A, ESP-VID2] are
configured in each MEP, where the ESP-MAC A is the same as the
local MEP's MAC and ESP-MAC B is the same as remote MEP's MAC.
The GMPLS Ethernet Label for forwarding, as defined in
[GELS-PBBTE], consists of the ESP-MAC DA and ESP-VID. Hence the
necessary reachability parameters for the MEPs can be obtained
from Ethernet Labels (i.e., carried in the "downstream" and
upstream labels). In the case of point-to-point VLAN connections,
MEPs need to be provisioned with the VLAN identifiers, which in
this case are derived similarly from the Ethernet Label.
Assuming the procedures described in [GELS-PBBTE] for bidirectional
PBB-TE Ethernet LSP establishment the MEP configuration should be as
follows. When the RSVP-TE signaling is initiated for the
bidirectional Ethernet LSP the local node generates a Path message
and:
o Allocates an Upstream Label from its MAC address (ESP-MAC A) and
locally selected VID (ESP-VID1), that it would like to use to
receive traffic;
o Inserts an Ethernet OAM Configuration TLV in the LSP_ATTRIBUTES
object, specifying the CCM Interval and MD Level;
o Adds an MD Name Sub-TLV (optional) and a Short MA Name Sub-TLV to
the Ethernet OAM Configuration TLV, that will unambiguously
identify a Maintenance Association for this specific PBB-TE
connection. Note that values for these parameters may be derived
from the GMPLS LSP identification parameters;
o Adds a MEP ID Sub-TLV to the Ethernet OAM Configuration TLV. It
selects two distinct integer values to identify the local and
remote MEPs within the Maintenance Association created for
monitoring of the point-to-point PBB-TE connection.
Once the remote node receives the Path message it can use the
UPSTREAM_LABEL to extract the reachability information of the
initiator. Then it allocates a LABEL by selecting the MAC address
(ESP-MAC B) and VID (ESP-VID2) it would like to use to receive
traffic. These parameters determine the reachability information of
the local MEP. That is, the 3-tuples [ESP-MAC A, ESP-MAC B, ESP-
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VID1] and [ESP-MAC B, ESP-MAC A, ESP-VID2] are derived from the
Ethernet Labels. In addition the information received in the
Ethernet OAM Configuration TLV is used to configure the local MEP.
Once the Resv message successfully arrives to the initiator it can
extract the remote side's reachability information from the LABEL
object whereby this node has also obtained all the information needed
to establish its local MEP.
Once the MEPs are established the monitoring of the LSP is
operational. In certain situations, e.g., maintenance, re-
optimization of LSPs, it is desirable to explicitly enable or disable
the monitoring of LSPs (i.e., start/stop exchanging CC messages). To
allow administrative control of LSP monitoring the "Monitoring
Disabled" (M) bit in the ADMIN_STATUS Object is used [OAM-CONF-FWK].
3.2. OAM Configuration TLV
This TLV is specified in [OAM-CONF-FWK] and is used to select which
OAM technology/method should be used for the LSP. In this document a
new OAM Type: Ethernet OAM is defined.
OAM Type Description
------------ ------------------
0 Reserved
1 Ethernet OAM
2-256 Reserved
The receiving node when the Ethernet OAM Type is requested should
look for the corresponding technology specific Ethernet OAM
configuration TLV.
3.3. Ethernet OAM Configuration TLV
The Ethernet OAM Configuration TLV (depicted below) is defined for
Ethernet OAM specific configuration parameters. The Ethernet OAM
Configuration TLV is carried in the LSP_ATTRIBUTES object in Path
messages. This new TLV accommodates generic Ethernet OAM information
and carries sub-TLVs.
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type (3) (IANA) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Version |MD L.| Reserved (set to all 0s) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
~ sub TLVs ~
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type: indicates a new type: the Ethernet OAM Configuration TLV (3)
(IANA to define).
Length: indicates the total length including sub-TLVs.
Version: identifies the CFM protocol version according to [IEEE-CFM].
If a node does not support a specific CFM version an error must be
generated: "OAM Problem/Unsupported OAM Version"
MD L. (MD Level): indicates the desired MD Level. The values are
according to [IEEE-CFM]. If a node does not support a specific MD
Level an error must be generated: "OAM Problem/Unsupported OAM
Level".
3.3.1. MD Name Sub-TLV
The optional MD Name sub-TLV 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type (1) (IANA) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Format | Name Length | Reserved (set to all 0s) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
~ MD Name ~
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type: 1, MD Name Sub-TLV (IANA).
Length: indicates the total length of the TLV including padding.
Format: according to [IEEE-CFM].
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Name Length: the length of the MD Name field in bytes. This is
necessary to allow non 4 byte padded MD Name lengths.
MD Name: variable length field, formatted according to the format
specified in the Format field.
If an undefined Format is specified an error must be generated: "OAM
Problem/Unknown MD Name Format". Also the combined length of MD Name
and Short MA Name must be less or equal to 44bytes, if this is
violated an error must be generated: "OAM Problem/Name Length
Problem". Note that it is allowed to have no MD Name, as such the MD
Name sub-TLV is optional. In this case the MA Name must uniquely
identify a Maintenance Association.
3.3.2. Short MA Name Sub-TLV
The Short MA Name sub-TLV 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type (2) (IANA) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Format | Name Length | Reserved (set to all 0s) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
~ Short MA Name ~
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type: 2, Short MA Name Sub-TLV (IANA)
Length: indicates the total length of the TLV including padding.
Format: according to [IEEE-CFM].
Name Length: the length of the MA Name field in bytes. This is
necessary to allow non 4 byte padded MA Name lengths.
Short MA Name: variable length field formatted according to the
format specified in the Format field.
If an undefined Format is specified an error must be generated: "OAM
Problem/Unknown MA Name Format". Also the combined length of MD Name
and Short MA Name must be less or equal to 44bytes, if this is
violated an error must be generated: "OAM Problem/Name Length
Problem". Note that it is allowed to have no MD Name, in this case
the MA Name must uniquely identify a Maintenance Association.
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3.3.3. MEP ID Sub-TLV
The MEP ID Sub-TLV 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type (3) (IANA) | Length (4) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Local MEP ID |T|R| Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Remote MEP ID |T|R| Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type: 3, MEP ID Sub-TLV (IANA)
Length: indicates the total length of the TLV including padding.
Local MEP ID: a 16 bit integer value in the range 1-8191 of the MEP
ID on the initiator side.
Remote MEP ID: a 16 bit integer value in the range 1-8191 of the MEP
ID to be set for the MEP established at the receiving side. This
value is determined by the initiator node. This is possible, since a
new MAID is assigned to each PBB-TE connection, and MEP IDs must be
only unique within the scope of the MAID.
Two flags are defined Transmit (T) and Receive (R). When T is set
the corresponding MEP must send OAM packets. When R is set the
corresponding MEP must expect to receive OAM packets. These flags
are used to configure the role of MEPs.
3.3.4. Continuity Check (CC) Sub-TLV
The Continuity Check (CC) sub-TLV 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type (4) (IANA) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Prio | CCM I | Reserved (set to all 0s) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Prio: Indicates the priority to be set for CCM frames. In Ethernet 3
bits carried in VLAN TAGs identify priority information.
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CCM I (CCM Interval): CCM Interval, according to the 3 bit encoding
[IEEE-CFM] shown in Table 1. If a node does not support the
requested CCM Interval an error must be generated: "OAM Problem/
Unsupported CC Interval".
3.4. Pro-active Performance Monitoring
Ethernet OAM functions for Performance Monitoring (PM) allow
measurements of different performance parameters including Frame Loss
Ratio, Frame Delay and Frame Delay variation as defined in the ITU-T
Y.1731 recommendation. Only a subset of PM functions are operated in
a pro-active fashion to monitor the performance of the connection
continuously. Pro-active PM supports Fault Management functions, by
providing an indication of decreased service performance and as such
may provide triggers to initiate recovery procedures.
While on demand PM functions are always initiated by management
commands, for pro-active PM it may be desirable to utilize the
control plane for configuration and activation together with Fault
Management functions such as Continuity Check.
ITU-T Y.1731 defines dual-ended Loss Measurement as pro-active OAM
for performance monitoring and as a PM function applicable to fault
management. For dual-ended Loss Measurement each MEP piggy-backs
transmitted and received frame counters on CC messages; to support
and synchronize bidirectional Loss Measurements at the MEPs. Dual-
ended Loss Measurement is invoked by setting the Performance
Monitoring/Loss OAM Function flag in the OAM Configuration TLV
[OAM-CONF-FWK]. Besides configuring the Continuity Check
functionality, no additional configuration is required for this type
of Loss Measurement.
3.5. Ethernet OAM configuration errors
In addition to error values specified in [OAM-CONF-FWK] this document
defines the following values for the "OAM Problem" Error Code.
o If a node does not support a specific CFM version an error must be
generated: "OAM Problem/Unsupported OAM Version".
o If a node does not support a specific MD Level an error must be
generated: "OAM Problem/Unsupported OAM Level".
o If an undefined MD name format is specified an error must be
generated: "OAM Problem/Unknown MD Name Format".
o If an undefined MA name format is specified an error must be
generated: "OAM Problem/Unknown MA Name Format".
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o If the combined length of MD Name and Short MA Name must be less
or equal to 44bytes, if this is violated an error must be
generated: "OAM Problem/Name Length Problem".
o If a node does not support the requested CCM Interval an error
must be generated: "OAM Problem/Unsupported CC Interval".
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4. IANA Considerations
This document specifies a new Ethernet OAM Configuration TLV to be
carried in the OAM Configuration TLV in LSP_ATTRIBUTES and
LSP_REQUIRED_ATTRIBUTES objects in Path messages.
The following values need to be assigned under the Error Code: "OAM
Problem": "Unsupported OAM Version", "Unsupported OAM Level",
"Unknown MD Name Format", "Unknown MA Name Format", "Name Length
Problem", "Unsupported CC Interval".
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5. 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 would request
liveliness monitoring, with frequent periodic messages, for a high
number of LSPs, targeting a single network element.
Security aspects will be covered in more detailed in subsequent
versions of this document.
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6. Acknowledgements
The authors would like to thank Francesco Fondelli, Adrian Farrel,
Loa Andersson, Eric Gray and Dimitri Papadimitriou for their useful
comments.
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7. References
[GELS-Framework]
"GMPLS Ethernet Label Switching Architecture and
Framework", Internet Draft, work in progress.
[GELS-PBBTE]
"GMPLS control of Ethernet PBB-TE", Internet Draft, work
in progress.
[GMPLS-OAM]
"OAM Requirements for Generalized Multi-Protocol Label
Switching (GMPLS) Networks", Internet Draft, work in
progress.
[IEEE-CFM]
"IEEE 802.1ag, Draft Standard for Connectivity Fault
Management", work in progress.
[IEEE-PBBTE]
"IEEE 802.1Qay Draft Standard for Provider Backbone
Bridging Traffic Engineering", work in progress.
[OAM-CONF-FWK]
"OAM Configuration Framework for GMPLS RSVP-TE", Internet
Draft, work in progress.
[RFC3469] "Framework for Multi-Protocol Label Switching (MPLS)-based
Recovery", RFC 3469, February 2003.
[RFC3471] "Generalized Multi-Protocol Label Switching (GMPLS)
Signaling Functional Description", RFC 3471, January 2003.
[RFC3473] "Generalized Multi-Protocol Label Switching (GMPLS)
Signaling Resource ReserVation Protocol-Traffic
Engineering (RSVP-TE) Extensions", RFC 3473, January 2003.
[RFC4377] "Operations and Management (OAM) Requirements for Multi-
Protocol Label Switched (MPLS) Networks", RFC 4377,
February 2006.
[RFC4420] "Encoding of Attributes for Multiprotocol Label Switching
(MPLS) Label Switched Path (LSP) Establishment Using
Resource ReserVation Protocol-Traffic Engineering
(RSVP-TE)", RFC 4420, February 2006.
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Authors' Addresses
Attila Takacs
Ericsson
Laborc u. 1.
Budapest, 1037
Hungary
Email: attila.takacs@ericsson.com
Balazs Gero
Ericsson
Laborc u. 1.
Budapest, 1037
Hungary
Email: balazs.gero@ericsson.com
Don Fedyk
Nortel
600 Technology Park Drive
Billerica, MA 01821
USA
Email: dwfedyk@nortel.com
Dinesh Mohan
Nortel
3500 Carling Ave
Ottawa, ON, K2H8E9
Canada
Email: mohand@nortel.com
Hao Long
Huawei
Email: lonho@huawei.com
Takacs, et al. Expires September 10, 2009 [Page 20]
Internet-Draft GMPLS based Ethernet OAM Configuration March 2009
Takacs, et al. Expires September 10, 2009 [Page 21]
