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Internet Engineering Task Force (IETF)                     D. Frost, Ed.Request for Comments: 6375                                S. Bryant, Ed.Category: Informational                                    Cisco SystemsISSN: 2070-1721                                           September 2011A Packet Loss and Delay Measurement Profilefor MPLS-Based Transport NetworksAbstract   Procedures and protocol mechanisms to enable efficient and accurate   measurement of packet loss, delay, and throughput in MPLS networks   are defined inRFC 6374.   The MPLS Transport Profile (MPLS-TP) is the set of MPLS protocol   functions applicable to the construction and operation of packet-   switched transport networks.   This document describes a profile of the general MPLS loss, delay,   and throughput measurement techniques that suffices to meet the   specific requirements of MPLS-TP.   This document is a product of a joint Internet Engineering Task Force   (IETF) / International Telecommunication Union Telecommunication   Standardization Sector (ITU-T) effort to include an MPLS Transport   Profile within the IETF MPLS and Pseudowire Emulation Edge-to-Edge   (PWE3) architectures to support the capabilities and functionalities   of a packet transport network as defined by the ITU-T.Status of This Memo   This document is not an Internet Standards Track specification; it is   published for informational purposes.   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).  Not all documents   approved by the IESG are a candidate for any level of Internet   Standard; seeSection 2 of RFC 5741.   Information about the current status of this document, any errata,   and how to provide feedback on it may be obtained athttp://www.rfc-editor.org/info/rfc6375.Frost & Bryant                Informational                     [Page 1]

RFC 6375           MPLS-TP Loss and Delay Measurement     September 2011Copyright Notice   Copyright (c) 2011 IETF Trust and the persons identified as the   document authors.  All rights reserved.   This document is subject toBCP 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   carefully, as they describe your rights and restrictions with respect   to this document.  Code Components extracted from this document must   include Simplified BSD License text as described in Section 4.e of   the Trust Legal Provisions and are provided without warranty as   described in the Simplified BSD License.1.  Introduction   Procedures for the measurement of packet loss, delay, and throughput   in MPLS networks are defined in [RFC6374].  This document describes a   profile, i.e., a simplified subset, of these procedures that suffices   to meet the specific requirements of MPLS-based transport networks   [RFC5921] as defined in [RFC5860].  This profile is presented for the   convenience of implementors who are concerned exclusively with the   transport network context.   The use of the profile specified in this document is purely optional.   Implementors wishing to provide enhanced functionality that is within   the scope of [RFC6374] but outside the scope of this profile may do   so, whether or not the implementation is restricted to the transport   network context.   The assumption of this profile is that the devices involved in a   measurement operation are configured for measurement by a means   external to the measurement protocols themselves, for example, via a   Network Management System (NMS) or separate configuration protocol.   The manageability considerations in [RFC6374] apply, and further   information on MPLS-TP network management can be found in [RFC5950].   This document is a product of a joint Internet Engineering Task Force   (IETF) / International Telecommunication Union Telecommunication   Standardization Sector (ITU-T) effort to include an MPLS Transport   Profile within the IETF MPLS and Pseudowire Emulation Edge-to-Edge   (PWE3) architectures to support the capabilities and functionalities   of a packet transport network as defined by the ITU-T.Frost & Bryant                Informational                     [Page 2]

RFC 6375           MPLS-TP Loss and Delay Measurement     September 20112.  MPLS-TP Measurement Considerations   The measurement considerations discussed inSection 2.9 of [RFC6374]   apply also in the context of MPLS-TP, except for the following, which   pertain to topologies excluded from MPLS-TP:   o  Equal Cost Multipath considerations (Section 2.9.4 of [RFC6374])   o  Considerations for direct Loss Measurement (LM) in the presence of      Label Switched Paths constructed via the Label Distribution      Protocol (LDP) or utilizing Penultimate Hop Popping (Section 2.9.8      of [RFC6374])3.  Packet Loss Measurement (LM) Profile   When an LM session is externally configured, the values of several   protocol parameters can be fixed in advance at the endpoints involved   in the session, so that negotiation of these parameters is not   required.  These parameters, and their default values as specified by   this profile, are as follows:   Parameter                                 Default Value   ----------------------------------------- --------------------------   Query control code                        In-band Response Requested   Byte/packet Count (B) Flag                Packet count   Traffic-class-specific (T) Flag           Traffic-class-scoped   Origin Timestamp Format (OTF)             Truncated IEEE 1588v2   A simple implementation may assume that external configuration will   ensure that both ends of the communication are using the default   values for these parameters.  However, implementations are strongly   advised to validate the values of these parameters in received   messages so that configuration inconsistencies can be detected and   reported.   LM message rates (and test message rates, when inferred LM is used)   should be configurable by the network operator on a per-channel   basis.  The following intervals should be supported:   Message Type   Supported Intervals   -------------- ------------------------------------------------------   LM Message     100 milliseconds, 1 second, 10 seconds, 1 minute, 10                  minutes   Test Message   10 milliseconds, 100 milliseconds, 1 second, 10                  seconds, 1 minuteFrost & Bryant                Informational                     [Page 3]

RFC 6375           MPLS-TP Loss and Delay Measurement     September 20114.  Packet Delay Measurement (DM) Profile   When a DM session is externally configured, the values of several   protocol parameters can be fixed in advance at the endpoints involved   in the session, so that negotiation of these parameters is not   required.  These parameters, and their default values as specified by   this profile, are as follows:   Parameter                                  Default Value   ------------------------------------------ --------------------------   Query control code                         In-band Response Requested   Querier Timestamp Format (QTF)             Truncated IEEE 1588v2   Responder Timestamp Format (RTF)           Truncated IEEE 1588v2   Responder's Preferred Timestamp Format     Truncated IEEE 1588v2   (RPTF)   A simple implementation may assume that external configuration will   ensure that both ends of the communication are using the default   values for these parameters.  However, implementations are strongly   advised to validate the values of these parameters in received   messages so that configuration inconsistencies can be detected and   reported.   DM message rates should be configurable by the network operator on a   per-channel basis.  The following message intervals should be   supported: 1 second, 10 seconds, 1 minute, 10 minutes.5.  Security Considerations   This document delineates a subset of the procedures specified in   [RFC6374], and as such introduces no new security considerations in   itself.  The security considerations discussed in [RFC6374] also   apply to the profile presented in this document.  General   considerations for MPLS-TP network security can be found in   [SECURITY-FRAMEWORK].Frost & Bryant                Informational                     [Page 4]

RFC 6375           MPLS-TP Loss and Delay Measurement     September 20116.  References6.1.  Normative References   [RFC5860]  Vigoureux, M., Ward, D., and M. Betts, "Requirements for              Operations, Administration, and Maintenance (OAM) in MPLS              Transport Networks",RFC 5860, May 2010.   [RFC6374]  Frost, D. and S. Bryant, "Packet Loss and Delay              Measurement for MPLS Networks",RFC 6374, September 2011.6.2.  Informative References   [RFC5921]  Bocci, M., Bryant, S., Frost, D., Levrau, L., and L.              Berger, "A Framework for MPLS in Transport Networks",RFC 5921, July 2010.   [RFC5950]  Mansfield, S., Gray, E., and K. Lam, "Network Management              Framework for MPLS-based Transport Networks",RFC 5950,              September 2010.   [SECURITY-FRAMEWORK]              Fang, L., Niven-Jenkins, B., and S. Mansfield, "MPLS-TP              Security Framework", Work in Progress, May 2011.Authors' Addresses   Dan Frost (editor)   Cisco Systems   EMail: danfrost@cisco.com   Stewart Bryant (editor)   Cisco Systems   EMail: stbryant@cisco.comFrost & Bryant                Informational                     [Page 5]