--- 1/draft-ietf-mpls-lsp-ping-reply-mode-simple-02.txt 2015-05-01 21:14:53.593531369 -0700 +++ 2/draft-ietf-mpls-lsp-ping-reply-mode-simple-03.txt 2015-05-01 21:14:53.621532052 -0700 @@ -1,23 +1,23 @@ Internet Engineering Task Force N. Akiya Internet-Draft Big Switch Networks Updates: 7110 (if approved) G. Swallow Intended status: Standards Track C. Pignataro -Expires: October 15, 2015 Cisco Systems +Expires: November 2, 2015 Cisco Systems L. Andersson M. Chen Huawei - April 13, 2015 + May 1, 2015 Label Switched Path (LSP) Ping/Traceroute Reply Mode Simplification - draft-ietf-mpls-lsp-ping-reply-mode-simple-02 + draft-ietf-mpls-lsp-ping-reply-mode-simple-03 Abstract The Multiprotocol Label Switching (MPLS) Label Switched Path (LSP) Ping and Traceroute use the Reply Mode field to signal the method to be used in the MPLS echo reply. This document updates the "Reply via Specified Path (5)" Reply Mode value to easily indicate the reverse LSP. This document also adds an optional TLV which can carry ordered list of Reply Mode values. @@ -37,21 +37,21 @@ Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at http://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." - This Internet-Draft will expire on October 15, 2015. + This Internet-Draft will expire on November 2, 2015. 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 publication of this document. Please review these documents @@ -70,21 +70,21 @@ 3.2. Reply Mode Order TLV . . . . . . . . . . . . . . . . . . 6 4. Relations to Other LSP Ping/Trace Features . . . . . . . . . 7 4.1. Reply Path TLV . . . . . . . . . . . . . . . . . . . . . 7 4.1.1. Example 1: Reply Mode Order TLV Usage with Reply Path TLV . . . . . . . . . . . . . . . . . . . . . . . . . 8 4.1.2. Example 2: Reply Mode Order TLV Usage with Reply Path TLV . . . . . . . . . . . . . . . . . . . . . . . . . 8 4.2. Proxy LSP Ping . . . . . . . . . . . . . . . . . . . . . 9 4.2.1. Proxy LSR Sending an MPLS Echo Request . . . . . . . 9 4.2.2. Proxy LSR Sending an MPLS Proxy Ping Reply . . . . . 9 - 5. Security Considerations . . . . . . . . . . . . . . . . . . . 9 + 5. Security Considerations . . . . . . . . . . . . . . . . . . . 10 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10 6.1. New Reply Mode Order TLV . . . . . . . . . . . . . . . . 10 7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 10 8. Contributing Authors . . . . . . . . . . . . . . . . . . . . 10 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 10 9.1. Normative References . . . . . . . . . . . . . . . . . . 10 9.2. Informative References . . . . . . . . . . . . . . . . . 11 Appendix A. Reply Mode Order TLV Beneficial Scenarios . . . . . 11 A.1. Incorrect Forwarding Scenario . . . . . . . . . . . . . . 11 A.2. Non-Co-Routed Bidirectional LSP Scenario . . . . . . . . 12 @@ -246,65 +246,69 @@ 0:0:0:0:0:FFFF:7F00/104 for IPv6. 3.2. Reply Mode Order TLV This document also introduces a new optional TLV to describe list of Reply Mode values. The new TLV will contain one or more Reply Mode value(s) in preferred order. The first Reply Mode value is the most preferred and the last Reply Mode value is the least preferred. Following rules apply when using Reply Mode Order TLV. - 1. The Reply Mode Order TLV MAY be included in MPLS echo request. + 1. The Reply Mode Order TLV MUST NOT be included in MPLS echo reply. + If the initiator LSR receives an MPLS echo reply with the Reply + Mode Order TLV, the initiator LSR MUST ignore the whole Reply + Mode Order TLV and MUST only use the value from the Reply Mode + field of the received MPLS echo reply. It may be beneficial for + implementations to provide counters and/or loggings, with + appropriate log dampening, to record this error case. - 2. The Reply Mode Order TLV MUST NOT be included in MPLS echo reply. + 2. The Reply Mode Order TLV MAY be included in MPLS echo request. 3. The Reply Mode field of an MPLS echo request MUST be set to a valid value even when supplying the Reply Mode Order TLV. The initiator LSR SHOULD set the Reply Mode field of MPLS echo request to a value that corresponds to a return path which most likely to be available, in case the responder LSR does not understand the Reply Mode Order TLV. 4. If a responder LSR understands the Reply Mode Order TLV but the - TLV is not valid (due to conditions described in the items 6, 8 - and 9 immediately below), then the responder LSR MUST only use - the value described in the Reply Mode field of received MPLS echo - request. + TLV is not valid (due to conditions described in the items 6, 7, + 8 and 9 immediately below), then the responder LSR MUST ignore + the whole Reply Mode Order TLV and MUST only use the value from + the Reply Mode field of the received MPLS echo request. It may + be beneficial for implementations to provide counters and/or + loggings, with appropriate log dampening, to record this error + case. 5. If a responder LSR understands the Reply Mode Order TLV and the TLV is valid, then the responder LSR MUST consider the Reply Mode values described in the TLV and MUST NOT use the value described in the Reply Mode field of received MPLS echo request. In other words, a valid Reply Mode Order TLV overrides the value specified in the Reply Mode field of received MPLS echo request. - 6. Reply Mode Order TLV MUST contain at least one Reply Mode value, - and SHOULD contain at least two Reply Mode values. + 6. Reply Mode Order TLV MUST contain at least one Reply Mode value. 7. A Reply Mode value, except for Reply Mode value 5 (Reply via Specified Path), MUST NOT be repeated (i.e., MUST NOT appear multiple times) in the Reply Mode Order TLV. 8. The Reply Mode value 5 (Reply via Specified Path) MAY be included more than once in the Reply Mode Order TLV. However, in such case a Reply Path TLV MUST be included for all instances of the Reply Mode value 5 included in the Reply Mode Order TLV. In other words, 3 instances of the Reply Mode value 5 in the Reply Mode Order TLV will require 3 instances of the Reply Path TLVs. 9. The Reply Mode value 1 (Do not reply) MUST NOT be used in the Reply Mode Order TLV. - If a responder LSR receives a Reply Mode Order TLV which does not - comply to the rules described above, then the responder LSR MUST - ignore the Reply Mode Order TLV. - The responder LSR is to select the first available return path in this TLV. Reply Mode value corresponding to the selected return path MUST be set in Reply Mode field of MPLS echo reply to communicate back to the initiator LSR which return path was chosen. The format of the TLV is as follows: 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+