draft-ietf-mpls-lsp-ping-ttl-tlv-06.txt   draft-ietf-mpls-lsp-ping-ttl-tlv-07.txt 
skipping to change at page 1, line 15 skipping to change at page 1, line 15
Intended Status: Standards Track George Swallow Intended Status: Standards Track George Swallow
Shaleen Saxena Shaleen Saxena
Cisco Systems Cisco Systems
Vishwas Manral Vishwas Manral
Hewlett Packard Co. Hewlett Packard Co.
Sam Aldrin Sam Aldrin
Huawei Technologies, Inc. Huawei Technologies, Inc.
Expires: April 19, 2014 October 16, 2013 Expires: September 25, 2014 March 24, 2014
Definition of Time-to-Live TLV for LSP-Ping Mechanisms Definition of Time-to-Live TLV for LSP-Ping Mechanisms
draft-ietf-mpls-lsp-ping-ttl-tlv-06.txt draft-ietf-mpls-lsp-ping-ttl-tlv-07.txt
Abstract Abstract
LSP-Ping is a widely deployed Operation, Administration, and LSP-Ping is a widely deployed Operation, Administration, and
Maintenance (OAM) mechanism in MPLS networks. However, in the present Maintenance (OAM) mechanism in MPLS networks. However, in the present
form, this mechanism is inadequate to verify connectivity of a form, this mechanism is inadequate to verify connectivity of a
segment of a Multi-Segment PseudoWire (MS-PW) from any node on the segment of a Multi-Segment PseudoWire (MS-PW) from any node on the
path of the MS-PW. This document defines a TLV to address this path of the MS-PW. This document defines a TLV to address this
shortcoming. shortcoming.
skipping to change at page 2, line 7 skipping to change at page 2, line 7
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
The list of current Internet-Drafts can be accessed at The list of current Internet-Drafts can be accessed at
http://www.ietf.org/1id-abstracts.html http://www.ietf.org/1id-abstracts.html
The list of Internet-Draft Shadow Directories can be accessed at The list of Internet-Draft Shadow Directories can be accessed at
http://www.ietf.org/shadow.html http://www.ietf.org/shadow.html
Copyright and License Notice Copyright and License Notice
Copyright (c) 2013 IETF Trust and the persons identified as the Copyright (c) 2014 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of (http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Time To Live TLV . . . . . . . . . . . . . . . . . . . . . . . 4 3. Time To Live TLV . . . . . . . . . . . . . . . . . . . . . . . 4
3.1. TTL TLV Format . . . . . . . . . . . . . . . . . . . . . . 4 3.1. TTL TLV Format . . . . . . . . . . . . . . . . . . . . . . 4
3.2. Usage . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 3.2. Usage . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
4. Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 4. Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
4.1. Traceroute mode . . . . . . . . . . . . . . . . . . . . . . 5 4.1. Traceroute mode . . . . . . . . . . . . . . . . . . . . . . 6
4.2. Error scenario . . . . . . . . . . . . . . . . . . . . . . 6 4.2. Error scenario . . . . . . . . . . . . . . . . . . . . . . 6
5. Security Considerations . . . . . . . . . . . . . . . . . . . . 6 5. Security Considerations . . . . . . . . . . . . . . . . . . . . 6
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 6 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 6
7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 6 7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 7
8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 7 8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 7
8.1 Normative References . . . . . . . . . . . . . . . . . . . 7 8.1 Normative References . . . . . . . . . . . . . . . . . . . 7
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 7 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 7
1. Introduction 1. Introduction
A MS-PW may span across multiple service provider networks. In order A MS-PW may span across multiple service provider networks. In order
to allow Service Providers (SP) to verify segments of such MS-PW from to allow Service Providers (SP) to verify segments of such MS-PW from
any node on the path of the MS-PW, any node along the path of the MS- any node on the path of the MS-PW, any node along the path of the MS-
PW, should be able to originate an LSP-Ping echo request packet to PW, should be able to originate an LSP-Ping echo request packet to
skipping to change at page 3, line 28 skipping to change at page 3, line 28
request MAY need to know how many hops away the originator of the request MAY need to know how many hops away the originator of the
echo request is so that it can set the TTL value on the MPLS header echo request is so that it can set the TTL value on the MPLS header
for the echo reply to be intercepted at the originator node. for the echo reply to be intercepted at the originator node.
In MPLS networks, for bidirectional co-routed LSPs, if it is desired In MPLS networks, for bidirectional co-routed LSPs, if it is desired
to verify connectivity from any intermediate node (LSR) on the LSP to to verify connectivity from any intermediate node (LSR) on the LSP to
the any other LSR on the LSP the receiver may need to know the TTL to the any other LSR on the LSP the receiver may need to know the TTL to
send the Echo reply with, so as the packet is intercepted by the send the Echo reply with, so as the packet is intercepted by the
originator node. originator node.
A new optional TTL TLV is being proposed in this document this TLV A new optional TTL TLV is defined in this document. This TLV will be
will be added by the originator of the echo request to inform the added by the originator of the echo request to inform the receiver
receiver how many hops away the originator is on the path of the MS- how many hops away the originator is on the path of the MS-PW or
PW or Bidirectional LSP. Bidirectional LSP.
The scope of this TTL TLV is currently limited to MS-PW or This mechanism only works if the echo reply is sent down the co-
Bidirectional co-routed MPLS LSPs. routed LSP, hence the scope of this TTL TLV is currently limited to
MS-PW or Bidirectional co-routed MPLS LSPs. The presence of the TLV
implies the use of the return path of the co-routed LSP, if the
return path is any other mechanism then the TLV in the echo request
MUST be ignored.
2. Terminology 2. Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119]. document are to be interpreted as described in RFC 2119 [RFC2119].
LSR: Label Switching Router LSR: Label Switching Router
MPLS-TP: MPLS Transport Profile MPLS-TP: MPLS Transport Profile
skipping to change at page 6, line 35 skipping to change at page 6, line 40
This draft allows the setting of the TTL value in the MPLS Label of This draft allows the setting of the TTL value in the MPLS Label of
an echo reply, so that it can be intercepted by an intermediate an echo reply, so that it can be intercepted by an intermediate
device. This can cause a device to get a lot of LSP Ping packets device. This can cause a device to get a lot of LSP Ping packets
which get redirected to the CPU. which get redirected to the CPU.
However the same is possible even without the changes mentioned in However the same is possible even without the changes mentioned in
this document. A device should rate limit the LSP ping packets this document. A device should rate limit the LSP ping packets
redirected to the CPU so that the CPU is not overwhelmed. redirected to the CPU so that the CPU is not overwhelmed.
6. IANA Considerations The recommendation in [RFC4379] security section applies, to check
the source address of the MPLS echo request, however the source
address can now be any node along the LSP path.
A faulty transit node changing the TTL TLV value could make the wrong
node reply to the MPLS echo request, and/or the wrong node to receive
the MPLS echo reply. An LSP trace may help identify the faulty
transit node.
6. IANA Considerations
IANA is requested to assign TLV type value to the following TLV from IANA is requested to assign TLV type value to the following TLV from
the "Multiprotocol Label Switching Architecture (MPLS) Label Switched the "Multiprotocol Label Switching Architecture (MPLS) Label Switched
Paths (LSPs) Parameters - TLVs" registry, "TLVs and sub-TLVs" sub- Paths (LSPs) Parameters - TLVs" registry, "TLVs and sub-TLVs" sub-
registry. registry.
Time To Live TLV (See Section 3). The value should be assigned from Time To Live TLV (See Section 3). The value must be assigned from the
the range (32768-49161) of optional TLV's which SHOULD be ignored if range (32768-49161) of optional TLVs.
an implementation does not support or understand them as defined in
section 3 of RFC 4379 [RFC4379].
7. Acknowledgements 7. Acknowledgements
The authors would like to thank Greg Mirsky for his comments. The authors would like to thank Greg Mirsky for his comments.
8. References 8. References
8.1 Normative References 8.1 Normative References
[1] K. Kompella, G. Swallow, "Detecting Multi-Protocol Label Switched [1] K. Kompella, G. Swallow, "Detecting Multi-Protocol Label Switched
(MPLS) Data Plane Failures", RFC 4379, February 2006. (MPLS) Data Plane Failures", RFC 4379, February 2006.
[2] T. Nadeau, et. al, "Pseudowire Virtual Circuit Connectivity [2] T. Nadeau, et. al, "Pseudowire Virtual Circuit Connectivity
skipping to change at page 7, line 22 skipping to change at page 7, line 32
[2] T. Nadeau, et. al, "Pseudowire Virtual Circuit Connectivity [2] T. Nadeau, et. al, "Pseudowire Virtual Circuit Connectivity
Verification (VCCV): A Control Channel for Pseudowires ", RFC 5085, Verification (VCCV): A Control Channel for Pseudowires ", RFC 5085,
December 2007. December 2007.
[3] Bradner, S., "Key words for use in RFCs to Indicate Requirement [3] Bradner, S., "Key words for use in RFCs to Indicate Requirement
Levels", BCP 14, RFC 2119, March 1997. Levels", BCP 14, RFC 2119, March 1997.
Authors' Addresses Authors' Addresses
Siva Sivabalan
Cisco Systems, Inc.
2000 Innovation Drive
Kanata, Ontario, K2K 3E8
Canada
Email: msiva@cisco.com
Sami Boutros Sami Boutros
Cisco Systems, Inc. Cisco Systems, Inc.
3750 Cisco Way 3750 Cisco Way
San Jose, California 95134 San Jose, California 95134
USA USA
Email: sboutros@cisco.com Email: sboutros@cisco.com
Siva Sivabalan
Cisco Systems, Inc.
2000 Innovation Drive
Kanata, Ontario, K2K 3E8
Canada
Email: msiva@cisco.com
George Swallow George Swallow
Cisco Systems, Inc. Cisco Systems, Inc.
300 Beaver Brook Road 300 Beaver Brook Road
Boxborough , MASSACHUSETTS 01719 Boxborough , MASSACHUSETTS 01719
United States United States
Email: swallow@cisco.com Email: swallow@cisco.com
Shaleen Saxena Shaleen Saxena
Cisco Systems, Inc. Cisco Systems, Inc.
1414 Massachusetts Avenue 1414 Massachusetts Avenue
 End of changes. 13 change blocks. 
23 lines changed or deleted 33 lines changed or added

This html diff was produced by rfcdiff 1.41. The latest version is available from http://tools.ietf.org/tools/rfcdiff/