Network Working Group George Swallow
Internet Draft Cisco Systems, Inc.
Category: Standards Track
Expiration Date: August 2004
Kireeti Kompella
Juniper Networks, Inc.
Dan Tappan
Cisco Systems, Inc.
February 2004
Label Switching Router Self-Test
draft-ietf-mpls-lsr-self-test-02.txt
Status of this Memo
This document is an Internet-Draft and is in full conformance with
all provisions of Section 10 of RFC2026. Internet-Drafts are working
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Copyright Notice
Copyright (C) The Internet Society (2004). All Rights Reserved.
Abstract
This document defines a means of self test for a Label-Switching
Router (LSR) to verify that its dataplane is functioning for
certain key Multi-Protocol Label Switching (MPLS) applications
including unicast forwarding based on LDP [LDP] and traffic
engineering tunnels based on [RSVP-TE]. A new Loopback FEC type
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Internet Draft draft-ietf-mpls-lsr-self-test-02.txt February 2004
is defined to allow an upstream neighbor to assist in the testing
at very low cost. MPLS Echo Request and MPLS Echo Reply messages
[LSP-Ping] are extended to do the actual probing.
Contents
1 Introduction ........................................... 3
1.1 Conventions ............................................ 3
2 Loopback FEC ........................................... 4
2.1 Loopback FEC Element ................................... 4
2.2 LDP Procedures ......................................... 5
3 Data Plane Self Test ................................... 5
3.1 Data Plane Verification Request / Reply Messages ....... 7
3.2 Downstream Verification Object ......................... 8
3.2.1 IPv4 Downstream Verification Object .................... 8
3.2.2 IPv6 Downstream Verification Object .................... 11
3.3 Reply-To Object ........................................ 13
3.3.1 IPv4 Reply-To Object ................................... 14
3.3.2 IPv6 Reply-To Object ................................... 14
3.4 Sending procedures ..................................... 15
3.5 Receiving procedures ................................... 16
3.6 Upstream Neighbor Verification ......................... 16
4 Security Considerations ................................ 17
5 IANA Considerations .................................... 17
6 Acknowledgments ........................................ 17
7 References ............................................. 18
7.1 Normative References ................................... 18
7.2 Informative References ................................. 18
8 Authors' Addresses ..................................... 18
9 Intellectual Property Notice ........................... 19
10 Full Copyright Statement ............................... 19
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1. Introduction
This document defines a means of self test for a Label-Switching
Router (LSR) to verify that its dataplane is functioning for certain
key Multi-Protocol Label Switching (MPLS) applications including
unicast forwarding based on LDP [LDP] and traffic engineering tunnels
based on [RSVP-TE]. MPLS Echo Request and MPLS Echo Reply messages
[LSP-Ping] messages are extended to do the actual probing. The pings
are sent to an upstream neighbor, looped back through the LSR under
test and intercepted, by means of TTL expiration by a downstream
neighbor. Extensions to LSP-Ping [LSP-Ping] are defined to allow the
down stream neighbor to report the test results.
In order to minimize the load on upstream LSRs a new loopback FEC is
defined. Receipt of a packet labeled with a loopback label will cause
the advertising LSR to pop the label off the label stack and send the
packet out the advertised interface.
Note that use of a loopback allows an LSR to test label entries for
which the LSR is not currently some neighbor's next hop. In this way
label entries can be verified prior to the occurrence of a routing
change.
Some routing protocls, most notably OSPF have no means of exchanging
the "Link Local Identifiers" used to identify unnumbered links and
components of bundled links. These test procedures can be used to
associate the neighbor's interfaces with the probing LSRs interfaces.
This is achieved by simply having the TTL of the MPLS Ping expire one
hop sooner, i.e. at the testing LSR itself.
1.1. Conventions
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 [KEYWORDS].
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2. Loopback FEC
The Loopback FEC type is defined to enable an upstream neighbor to
assist in LSR self-testing at very low cost. This FEC causes the
loopback to occur in the dataplane without control plane involvement
beyond the initial LDP exchange and dataplane setup.
An LSR uses the Loopback FEC to selectively advertise loopback labels
to its neighbor LSRs. Each loopback label is bound to a particular
interface. For multi-access links, a unique label for each neighbor
is required, since the link-level address is derived from the label
lookup. When an MPLS packet with its top label set to a loopback
label is received from an interface over which that label was
advertised, the loopback label is popped and the packet is sent on
the interface to which the loopback label was bound.
TTL treatment for loopback labels follows the Uniform model. I.e.
the TTL carried in the loopback label is decremented and copied to
the exposed label or IP header as the case may be.
2.1. Loopback FEC Element
FEC element type 130 is used. The FEC element is encoded as
follows: (note: 130 is provisionally assigned, the actual value will
be assigned by IANA.)
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 130 | Res | Interface Type| Id Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Interface Identifier |
| " |
| " |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Reserved (Res)
Must be set to zero on transmission and ignored on receipt.
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Interface Type
# Type Interface Identifier
--- ---- --------------------
0 Unnumbered A 32 bit Link Identifier as
defined in [RFC3477]
1 IPv4 Numbered IPv4 Address
2 IPv6 Numbered IPv6 Address
Identifier Length
Length of the interface identifier in octets.
The length is 4 bytes for Unnumbered and IPv4, 16 bytes for IPv6.
Address
An identifier encoded according to the Identifier Type field.
2.2. LDP Procedures
It is RECOMMENDED that loopback labels only be distributed in
response to a Label Request message, irrespective of the label
advertisement mode of the LDP session. However it is recognized that
in certain cases such as OSPF with unnumbered links, the upstream LSR
may not have sufficiently detailed information of the neighbor's link
identifier to form the request. In these cases, the downstream LSR
will need to be configured to make unsolicited advertisements.
3. Data Plane Self Test
A self test operation involves three LSRs, the LSR doing the test, an
upstream neighbor and a downstream neighbor. We refer to these as
LSRs T, U, and D respectively. In order to minimize the processing
load on LSRD, two new LSP Ping messages are defined, called the MPLS
Data Plane Verification Request and the MPLS Data Plane Verification
Reply. These messages are used to allow LSRT to obtain the label
stack, address and interface information of LSRD.
If FEC verification is required, the MPLS Echo Request and Reply
messages are used.
The packet flow is shown below. Although the figure shows LSRD
adjacent to LSRT it may in some cases be an arbitrary number of hops
away.
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+------+ +------+ +------+
| ,-|-------|<DPVRq| | |
| `-|-------|------|-------|-> |
| | | <-|-------|<DPVRp|
+------+ +------+ +------+
LSRU LSRT LSRD
DPVRq: MPLS Data Plane Verification Request
DPVRp: MPLS Data Plane Verification Reply
Figure 1: Self Test Message Flow
In order to perform a test on an incoming label stack, LSRT forms an
MPLS Data Plane Verification Request. Included in that is a Data
Plane Verification Object which requests that the interface and label
stack seen by LSRD be returned. Optionally LSRT could have included
FEC Stack TLV to verify that LSRD's labels are mapped to the expected
FECs. In that case an MPLS Echo Request Message would have been
used.
LSRT prepends the packet with the incoming label stack being tested
and the loopback label received from LSRU. The TTL values are set
such that they will expire at LSRD. LSRT then forwards the packet to
LSRU.
LSRU receives the packet and performs normal MPLS forwarding. That
is, the loopback label is popped, the TTL is decremented and
propagated (in this case) to the exposed label.
LSRT receives the packet and performs normal MPLS forwarding. If
everything is functioning as expected this will cause the packet to
arrive at LSRD with a TTL of 1.
In this example, we assume that all is working properly. The TTL
expires at LSRD causing it to receive the packet LSRD notes the the
interface and the label stack on which the packet was received and
records these in a Downstream Verification TLV. The results are
recorded in an MPLS Data Plane Verification Reply message and sent to
LSRT.
If a FEC Stack TLV had been included, the procedures in [LSP-Ping]
would be followed. Additionally, a Downstream Verification TLV would
be included in the MPLS Echo Reply message.
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3.1. Data Plane Verification Request / Reply Messages
Two new LSP Ping messages are defined for LSR self test. The purpose
of the new messages is two fold. First the timestamps are removed to
minimize processing. Second the message type allows simple
recognition that minimal processing is necessary to service this
request. The definitions of all fields are identical to those found
in [LSP-PING].
The new message types are: (Provisionally; to be assigned)
Type Message
---- -------
3 MPLS Data Plane Verification Request
4 MPLS Data Plane Verification Reply
The messages have the following format:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Version Number | Must Be Zero |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Message Type | Reply mode | Return Code | Return Subcode|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sender's Handle |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sequence Number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| TLVs ... |
. .
. .
. .
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The MPLS Data Plane Verification Request message MAY contain the
following objects:
Type # Object
------ -----------
3 Pad
5 Vendor Enterprise Code
7 (tba) IPv4 Downstream Verification Object
8 (tba) IPv6 Downstream Verification Object
9 (tba) IPv4 Reply-to Object
10 (tba) IPv6 Reply-to Object
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The MPLS Data Plane Verification Reply message MAY contain the
following objects:
Type # Object
------ -----------
3 Pad
4 Error Code
5 Vendor Enterprise Code
7 (tba) IPv4 Downstream Verification Object
8 (tba) IPv6 Downstream Verification Object
3.2. Downstream Verification Object
The Downstream Verification Object is an optional TLV in an MPLS Echo
Request or MPLS Verification Request message. Only one such object
may appear. It's presence signifies a request that a Downstream
Verification Object be included in the corresponding reply message.
The purpose of the object is to allow the upstream router to obtain
the exact interface and label stack information as it appears at the
replying LSR. It has two formats, type 7 for IPv4 and type 8 for
IPv6 (to be assigned by IANA).
3.2.1. IPv4 Downstream Verification Object
In a request message the Length is always 12. In a reply message the
length is 16 + 4*N octets, N is the number of Downstream Labels. The
value field of a Downstream Verification TLV has the following
format:
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Flags | Address Type | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Downstream IPv4 Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Downstream Interface Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
. .
. .
. Label Stack .
. .
. .
. .
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Flags
Two flags are defined as shown. All other flags are reserved
and MUST be set to zero.
+-+-+-+-+-+-+-+-+
|0|0|0|0|0|0|V|R|
+-+-+-+-+-+-+-+-+
The R flag can only be set in a request message. It requests
that the receiving router verify that the Downstream IPv4
Address is an address belonging to this router.
The V flag can only be set in a reply message. The flag is set
as a positive verification response to a received R flag. If
the R flag was not set in the request this Flag MUST be set
to zero.
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Address Type
The Address Type indicates if the interface is numbered or
unnumbered and is set to one of the following values:
Address Type Value
------------ -----
No Address 0
IPv4 1
Unnumbered 2
The value 0, "No Address" is only valid in a Verification
Request message.
Reserved
MUST be set to zero on transmission and ignored on receipt.
Downstream IPv4 Address
If the address type is 'No Address', the address field MUST be
set to zero and ignored on receipt.
If the address type is 'IPv4', the address field MUST either be
set to the downstream LSR's Router ID or the downstream LSR's
interface address.
If the address type is 'unnumbered', the address field MUST be set
to the downstream LSR's Router ID.
Downstream Interface Address
If the address type is 'IPv4', the interface address field MUST
MUST be set to the downstream LSR's interface address.
If the address type is 'unnumbered', interface address field
MUST be set to the index assigned by the downstream LSR to the
interface.
Label Stack
The label stack of the received echo request message. If any
TTL values have been changed by this router, they SHOULD be
restored.
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3.2.2. IPv6 Downstream Verification Object
In a request message the Length is always 24. In a reply message the
length is 40 + 4*N octets, N is the number of Downstream Labels. The
value field of a Downstream Verification TLV has the following
format:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Flags | Address Type | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Downstream IPv6 Address |
| Downstream IPv6 Address (Cont.) |
| Downstream IPv6 Address (Cont.) |
| Downstream IPv6 Address (Cont.) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Downstream Interface Address |
| Downstream Interface Address (Cont.) |
| Downstream Interface Address (Cont.) |
| Downstream Interface Address (Cont.) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
. .
. .
. Label Stack .
. .
. .
. .
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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Flags
Two flags are defined as shown. All other flags are reserved
and MUST be set to zero.
+-+-+-+-+-+-+-+-+
|0|0|0|0|0|0|V|R|
+-+-+-+-+-+-+-+-+
The R flag can only be set in a request message. It requests
that the receiving router verify that the Downstream IPv6
Address is an address belonging to this router.
The V flag can only be set in a reply message. The flag is set
as a positive verification response to a received R flag. If
the R flag was not set in the echo request this Flag MUST be set
to zero.
Address Type
The Address Type indicates if the interface is numbered or
unnumbered and is set to one of the following values:
Address Type Value
------------ -----
No Address 0
IPv6 1
Unnumbered 2
The value 0, "No Address" is only valid in a Verification
Request message.
Reserved
MUST be set to zero on transmission and ignored on receipt.
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Downstream IPv6 Address
If the address type is 'No Address', the address field MUST be
set to zero and ignored on receipt.
If the address type is 'IPv6', the address field MUST either be
set to the downstream LSR's Router ID or the downstream LSR's
interface address.
If the address type is 'unnumbered', the address field MUST be set
to the downstream LSR's Router ID.
Downstream Interface Address
If the address type is 'IPv6', the interface address field MUST
MUST be set to the downstream LSR's interface address.
If the address type is 'unnumbered', first four octets of
interface address field MUST be set to the index assigned by the
downstream LSR to the interface. The remaining 12 octets MUST
be set to zero.
Label Stack
The label stack of the received echo request message. If any
TTL values have been changed by this router, they SHOULD be
restored.
3.3. Reply-To Object
In order to perform detailed diagnostics of a particular failing flow
in the face of ECMP, it is useful to be able to use the exact source
and destination addresses of that flow. The Reply-To Object is an
optional TLV in a MPLS Data Plane Verification Request message. The
Object has two formats, type 9 for IPv4 and type 10 for IPv6 (to be
assigned by IANA).
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3.3.1. IPv4 Reply-To Object
The length of an IPv4 Reply-To Object is 5 octets; the value field
has the following format:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reply-to IPv4 Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| DS-Byte |
+-+-+-+-+-+-+-+-+
Reply-to IPv4 Address
The address to which the MPLS Data Plane Verification Reply
message is to be sent.
DS-Byte
The DS-Byte to be used in the MPLS Data Plane Verification Reply
packet.
3.3.2. IPv6 Reply-To Object
The length of an IPv6 Reply-To Object is 17 octets; the value field
has the following format:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reply-to IPv6 Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reply-to IPv6 Address (Cont.) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reply-to IPv6 Address (Cont.) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reply-to IPv6 Address (Cont.) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| DS-Byte |
+-+-+-+-+-+-+-+-+
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Reply-to IPv6 Address
The address to which the MPLS Data Plane Verification Reply
message is to be sent.
DS-Byte
The DS-Byte to be used in the MPLS Data Plane Verification Reply
packet.
3.4. Sending procedures
In order to perform a test on an incoming label stack, an LSR first
determines the expected outgoing label stack, next hop router and
next hop interface.
The LSR creates an MPLS Data Plane Verification Request message and
includes a Data Plane Verification Object. Optionally a FEC Stack
TLV may be included. In this case an MPLS Echo Request Message MUST
be used.
In normal use, the source address is set to an address belonging to
the LSR and the destination set to an address in the range of 127/8.
The IP TTL SHOULD be set to 1. The incoming label stack is prepended
to the packet. The TTL of these labels SHOULD be set to appropriate
values - 2 for those labels which will be process by this when the
packet is looped back; 1 for those labels which will be carried
through. Finally the loopback label bound to the incoming interface
is prepended to the packet. The TTL is set such that it will have
the value of 3 on the wire.
The packet is sent to the upstream neighbor on an interface for which
the loopback label is valid.
In diagnostic situations, the source and destination addresses MAY be
set to any value. In this case, a Reply-to IPv4 or IPv6 Object MUST
be included. The IP TTL MUST be set to 1. The TTL of labels other
than the loopback label MUST be set to appropriate values - 2 for
those labels which will be process by this LSR when the packet is
looped back; 1 for those labels which will be carried through.
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3.5. Receiving procedures
An LSR X that receives an MPLS Verification Request message formats a
MPLS Verification Reply message. The Sender's Handle and Sequence
Number are copied from the Request message.
X then parses the packet to ensure that it is a well-formed packet,
and that the TLVs that are not marked "Ignore" are understood. If
not, X SHOULD send an MPLS echo reply with the Return Code set to
"Malformed echo request received" or "TLV not understood" (as
appropriate), and the Subcode set to zero. In the latter case, the
misunderstood TLVs (only) are included in the reply.
If the echo request is good, X notes the interface I over which the
echo was received, and the label stack with which it came. If the
MPLS echo request contained a Downstream Verification object, then X
must format this information as a Downstream Verification object and
include it in its MPLS echo reply message.
The source address of the Reply message MUST be an address of the
replying LSR. If the request included a Reply-to IPv4 or IPv6
Object, the MPLS Data Plane Verification Reply message MUST be sent
to that address. Otherwise the Reply message is sent to the source
address of the Verification Request message.
An LSR MUST be capable of filtering addresses that are to be replied
to. If a filter has been invoked (i.e. configured) and an address
does not pass the filter, then a reply MUST NOT be sent, and the
event SHOULD be logged.
3.6. Upstream Neighbor Verification
To verify that an upstream neighbor is properly echoing packets an
LSR may send an MPLS Data Plane Verification Request packet with the
TTL set so that the packet will expire upon reaching reaching itself.
This procedure not only tests that the neighbor is correctly
processing the loopback label, it also allow the node to verify the
neighbor's interface mapping.
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+------+ +------+ DPVRq: MPLS Data Plane
| ,-|-------|<DPVRq| Verification Request
| `-|-------|-> |
| | | |
+------+ +------+
LSRU LSRT
Figure 2: Upstream Neighbor Verification
No TLVs need to be included in the MPLS Data Plane Verification
Request. By noting the Sender's Handle and Sequence Number, as well
as the loopback label, LSRT is able to detect that a) the packet was
looped, and b) determine (or verify) the interface on which the
packet was received.
4. Security Considerations
Were loopback labels widely known, they might be subject to abuse.
It is therefore RECOMMENDED that loopback labels only be shared
between trusted neighbors. Further, if the loopback labels are drawn
from the Global Label Space, or any other label space shared across
multiple LDP sessions, it is RECOMMENDED that all loopback labels be
filtered from a session except those labels pertaining to interfaces
directly connected to the neighbor participating in that session.
5. IANA Considerations
TBD
6. Acknowledgments
The authors would like to thank Vanson Lim, Tom Nadeau, and Bob
Thomas for their comments and suggestions.
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7. References
7.1. Normative References
[RFC3036] Andersson, L. et al., "LDP Specification", January 2001.
[LSP-Ping] Bonica, R. et al., "Detecting MPLS Data Plane Liveness",
work-in-progress.
[RFC3477] Kompella, K. & Y. Rekhter, "Signalling Unnumbered Links
in Resource ReSerVation Protocol - Traffic Engineering
(RSVP-TE)", January 2003.
[KEYWORDS] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
7.2. Informative References
[RSVP-TE] Awduche, D., et al, "RSVP-TE: Extensions to RSVP for LSP
tunnels", RFC 3209, December 2001.
8. Authors' Addresses
Kireeti Kompella
Juniper Networks, Inc.
1194 N. Mathilda Ave.
Sunnyvale, CA 94089
Email: kireeti@juniper.net
George Swallow
Cisco Systems, Inc.
1414 Massachusetts Ave
Boxborough, MA 01719
Email: swallow@cisco.com
Dan Tappan
Cisco Systems, Inc.
1414 Massachusetts Ave
Boxborough, MA 01719
Email: tappan@cisco.com
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9. Intellectual Property Notice
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Copies of claims of rights made available for publication and any
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10. Full Copyright Statement
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Swallow, et al. Standards Track [Page 19]
Internet Draft draft-ietf-mpls-lsr-self-test-02.txt February 2004
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Swallow, et al. Standards Track [Page 20]
