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Versions: (draft-gandhi-spring-ioam-sr-mpls) 00 01 02 03

MPLS Working Group                                        R. Gandhi, Ed.
Internet-Draft                                                    Z. Ali
Intended status: Standards Track                             C. Filsfils
Expires: March 17, 2021                                     F. Brockners
                                                     Cisco Systems, Inc.
                                                                  B. Wen
                                                                V. Kozak
                                                                 Comcast
                                                      September 13, 2020


           MPLS Data Plane Encapsulation for In-situ OAM Data
                      draft-gandhi-mpls-ioam-sr-03

Abstract

   In-situ Operations, Administration, and Maintenance (IOAM) records
   operational and telemetry information in the data packet while the
   packet traverses a path between two nodes in the network.  This
   document defines how IOAM data fields are transported using the MPLS
   data plane encapsulation, including Segment Routing (SR) with MPLS
   data plane (SR-MPLS).

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
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   This Internet-Draft will expire on March 17, 2021.

Copyright Notice

   Copyright (c) 2020 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
   (https://trustee.ietf.org/license-info) in effect on the date of



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   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.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Conventions . . . . . . . . . . . . . . . . . . . . . . . . .   3
     2.1.  Requirement Language  . . . . . . . . . . . . . . . . . .   3
     2.2.  Abbreviations . . . . . . . . . . . . . . . . . . . . . .   3
   3.  IOAM Data Field Encapsulation in MPLS Header  . . . . . . . .   3
     3.1.  Indicator Labels  . . . . . . . . . . . . . . . . . . . .   6
   4.  Procedure for Edge-to-Edge IOAM . . . . . . . . . . . . . . .   6
     4.1.  Edge-to-Edge IOAM Indicator Label Allocation  . . . . . .   7
   5.  Procedure for Hop-by-Hop IOAM . . . . . . . . . . . . . . . .   7
     5.1.  Hop-by-Hop IOAM Indicator Label Allocation  . . . . . . .   8
   6.  Considerations for ECMP . . . . . . . . . . . . . . . . . . .   8
   7.  Node Capability . . . . . . . . . . . . . . . . . . . . . . .   9
   8.  Data Packets with SR-MPLS Header  . . . . . . . . . . . . . .   9
   9.  Security Considerations . . . . . . . . . . . . . . . . . . .  10
   10. IANA Considerations . . . . . . . . . . . . . . . . . . . . .  10
   11. References  . . . . . . . . . . . . . . . . . . . . . . . . .  10
     11.1.  Normative References . . . . . . . . . . . . . . . . . .  10
     11.2.  Informative References . . . . . . . . . . . . . . . . .  11
   Acknowledgements  . . . . . . . . . . . . . . . . . . . . . . . .  12
   Contributors  . . . . . . . . . . . . . . . . . . . . . . . . . .  12
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  12

1.  Introduction

   In-situ Operations, Administration, and Maintenance (IOAM) records
   operational and telemetry information within the packet while the
   packet traverses a particular network domain.  The term "in-situ"
   refers to the fact that the IOAM data fields are added to the data
   packets rather than being sent within the probe packets specifically
   dedicated to OAM or Performance Measurement (PM).  The IOAM data
   fields are defined in [I-D.ietf-ippm-ioam-data], and can be used for
   various use-cases for OAM and PM.  The IOAM data fields are further
   updated in [I-D.ietf-ippm-ioam-direct-export] for direct export use-
   cases and in [I-D.ietf-ippm-ioam-flags] for Loopback and Active
   flags.

   This document defines how IOAM data fields are transported using the
   MPLS data plane encapsulations, including Segment Routing (SR) with
   MPLS data plane (SR-MPLS).



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2.  Conventions

2.1.  Requirement 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 [RFC2119] [RFC8174]
   when, and only when, they appear in all capitals, as shown here.

2.2.  Abbreviations

   Abbreviations used in this document:

   ECMP      Equal Cost Multi-Path

   IOAM      In-situ Operations, Administration, and Maintenance

   MPLS      Multiprotocol Label Switching

   OAM       Operations, Administration, and Maintenance

   PM        Performance Measurement

   POT       Proof-of-Transit

   PSID      Path Segment Identifier

   SR        Segment Routing

   SR-MPLS   Segment Routing with MPLS Data plane

3.  IOAM Data Field Encapsulation in MPLS Header

   The IOAM data fields defined in [I-D.ietf-ippm-ioam-data] are used.
   IOAM data fields are carried in the MPLS header as shown in Figure 1
   and Figure 2.  More than one trace options can be present in the IOAM
   data fields.  The Indicator Label is added at the bottom of the MPLS
   label stack (S flag set to 1) to indicate the presence of the IOAM
   data field(s) in the MPLS header.

   The data packets with IOAM data fields carry only one Indicator Label
   in the MPLS header.  Any intermediate node that adds additional MPLS
   encapsulation in the MPLS header may further update the IOAM data
   fields in the header without inserting another Indicator Label.







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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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  Extension Label (15)                 | TC  |0|  TTL          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  IOAM Indicator Label                 | TC  |1|  TTL          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+<-+
   |  IOAM-Type    | IOAM HDR LEN  |    RESERVED                   |  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  I
   |                                                               |  O
   |                                                               |  A
   ~                 IOAM Option and Data Space                    ~  M
   |                                                               |  |
   |                                                               |  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+<-+
   |                                                               |
   |                                                               |
   |                 Payload + Padding                             |
   |                                                               |
   |                                                               |
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                Figure 1: IOAM Encapsulation in MPLS Header



























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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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  Extension Label (15)                 | TC  |0|  TTL          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  IOAM and Flow Indicator Label        | TC  |1|  TTL          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |0 0 1 0|      Flow label                       | Block Number  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+<-+
   |  IOAM-Type    | IOAM HDR LEN  |    RESERVED                   |  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  I
   |                                                               |  O
   |                                                               |  A
   ~                 IOAM Option and Data Space                    ~  M
   |                                                               |  |
   |                                                               |  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+<-+
   |                                                               |
   |                                                               |
   |                 Payload + Padding                             |
   |                                                               |
   |                                                               |
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

        Figure 2: IOAM Encapsulation with Flow Label in MPLS Header

   IOAM Indicator Label (IIL) and IOAM and Flow Indicator Label (IFIL)
   used are defined in this document.

   The fields related to the encapsulation of IOAM data fields in the
   MPLS header are defined as follows:

   IOAM-Type:  8-bit field defining the IOAM Option type, as defined in
     Section 7.2 of [I-D.ietf-ippm-ioam-data].

   IOAM HDR LEN:  8-bit unsigned integer.  Length of the IOAM HDR in
     4-octet units.

   RESERVED:  8-bit reserved field MUST be set to zero upon transmission
     and ignored upon receipt.

   IOAM Option and Data Space:  IOAM option header and data is present
     as defined by the IOAM-Type field, and is defined in Section 4 of
     [I-D.ietf-ippm-ioam-data].






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3.1.  Indicator Labels

   IOAM Indicator Label (value TBA1 or TBA3) and IOAM and Flow Indicator
   Label (value TBA2 or TBA4) are used to indicate the presence of the
   IOAM data field in the MPLS header.

   The IOAM and Flow Indicator Label (value TBA2 or TBA4) is used to
   carry a second label underneath with protocol value 0010b, 20-bit
   Flow Label and 8-bit Block Number.

   o  The protocol value 0010b allows to avoid incorrect IP header-based
      hashing over ECMP paths that uses the value 0x4 (for IPv4) and
      value 0x6 (for IPv6) [RFC4928].

   o  The Flow Label identifies the traffic flow that can be used for
      IOAM purpose, e.g. monitoring a specific traffic flow for latency.

   o  The Block Number can be used to aggregate the IOAM data collected
      in data plane, e.g. compute measurement metrics for each block of
      a flow.  It is also used to correlate the IOAM data on different
      nodes.

   Different Indicator Labels are used for E2E and HbH IOAM to optimize
   processing on transit nodes and for checking if IOAM data fields need
   to be processed.  If only edge nodes need to process IOAM data then
   E2E Indicator Label is used so that transit nodes can ignore it.  If
   both edge and transit nodes need to process IOAM data then HbH
   Indicator Label is used.

   The SR path computation needs to know the Maximum SID Depth (MSD)
   that can be imposed at each node/link of a given SR path [RFC8664].
   This ensures that the SID stack depth of a computed path does not
   exceed the number of SIDs the node is capable of imposing.  The MSD
   used for path computation MUST include the Indicator Labels.

4.  Procedure for Edge-to-Edge IOAM

   The Edge-to-Edge (E2E) IOAM includes IOAM Option-Type as Edge-to-Edge
   Option-Type [I-D.ietf-ippm-ioam-data].  This section summarizes the
   procedure for data encapsulation and decapsulation for Edge-to-Edge
   IOAM in MPLS header.

   o  The encapsulating node inserts the IOAM Indicator Label or IOAM
      Flow Indicator Label with Flow Label and one or more IOAM data
      field(s) in the MPLS header.  The procedure to generate the Flow
      Label is outside the scope of this document.





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   o  The decapsulating node "forwards and punts the timestamped copy"
      of the data packet including IOAM data fields when the node
      recognizes the IOAM Indicator Label and IOAM Flow Indicator Label.
      The copy of the data packet is punted to the slow path for OAM
      processing and is not necessarily punted to the control-plane.
      The receive timestamp is required by various E2E OAM use-cases.

   o  The decapsulating node processes the IOAM data field(s) using the
      procedures defined in [I-D.ietf-ippm-ioam-data].  An example of
      IOAM processing may be to export the data fields, send data fields
      via Telemetry, etc.

   o  The decapsulating node also pops the Indicator Label and the IOAM
      data fields from the MPLS header.

4.1.  Edge-to-Edge IOAM Indicator Label Allocation

   IOAM Indicator Label (value TBA1) and IOAM and Flow Indicator Label
   (value TBA2) are used to indicate the presence of the E2E IOAM data
   field in the MPLS header.  The E2E IOAM Indicator Label and IOAM and
   Flow Indicator Label can be allocated using one of the following
   methods:

   o  Labels assigned by IANA with value TBA1 and TBA2 from the Extended
      Special-Purpose MPLS Values [I-D.ietf-mpls-spl-terminology].

   o  Labels allocated by a Controller from the global table of the
      decapsulating node.  The Controller provisions the label on both
      encapsulating and decapsulating nodes.

   o  Labels allocated by the decapsulating node.  The signaling
      extension for this is outside the scope of this document.

5.  Procedure for Hop-by-Hop IOAM

   The Hop-by-Hop (HbH) IOAM includes IOAM Option-Types IOAM Pre-
   allocated Trace Option-Type, IOAM Incremental Trace Option-Type and
   IOAM Proof of Transit (POT) Option-Type [I-D.ietf-ippm-ioam-data].
   This section summarizes the procedure for data encapsulation and
   decapsulation for Hop-by-hop IOAM in MPLS header.

   o  The encapsulating node inserts the IOAM Indicator Label or IOAM
      Flow Indicator Label with Flow Label and one or more IOAM data
      field(s) in the MPLS header.  The procedure to generate the Flow
      Label is outside the scope of this document.

   o  The intermediate and decapsulating node enabled with IOAM
      functions "forwards and punts the timestamped copy" of the data



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      packet including IOAM data fields when the node recognizes the
      IOAM Indicator Label and IOAM Flow Indicator Label.  The copy of
      the data packet is punted to the slow path for OAM processing and
      is not necessarily punted to the control-plane.  The receive
      timestamp is required by various hop-by-hop OAM use-cases.

   o  The intermediate and decapsulating node processes the IOAM data
      field(s) using the procedures defined in
      [I-D.ietf-ippm-ioam-data].  An example of IOAM processing may be
      to export the data fields, send data fields via Telemetry, etc.

   o  The decapsulating node pops the Indicator Label and the IOAM data
      fields from the MPLS header.

5.1.  Hop-by-Hop IOAM Indicator Label Allocation

   IOAM Indicator Label (value TBA3) and IOAM and Flow Indicator Label
   (value TBA4) are used to indicate the presence of the HbH IOAM data
   field in the MPLS header.  The HbH IOAM Indicator Label and IOAM and
   Flow Indicator Label can be allocated using one of the following
   methods:

   o  Labels assigned by IANA with value TBA3 and TBA4 from the Extended
      Special-Purpose MPLS Values [I-D.ietf-mpls-spl-terminology].

   o  Labels allocated by a Controller from the network-wide global
      table.  The Controller provisions the labels on all nodes
      participating in IOAM functions along the data traffic path.

6.  Considerations for ECMP

   The encapsulating node needs to make sure the IOAM data field does
   not start with a well known IP protocol value (e.g. 0x4 for IPv4 and
   0x6 for IPv6) as it can alter the hashing function for ECMP that uses
   the IP header.  This can be achieved by using the IOAM and Flow
   Indicator Label (value TBA2 and TBA4) that follows by protocol value
   0010b.  This approach is consistent with utilizing 0000b or 0001b as
   the first nibble after the MPLS label stack, as described in
   [RFC4928] [RFC4385].

   Note that the hashing function for ECMP that uses the labels from the
   MPLS header may now include the Indicator Label.

   When entropy label [RFC6790] is used for hashing function for ECMP,
   the procedure defined in this document does not alter the hashing
   function.





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7.  Node Capability

   The decapsulating node that has to pop the Indicator Label, data
   fields, and perform the IOAM function may not be capable of
   supporting it.  The encapsulating node needs to know if the
   decapsulating node can support the IOAM function.  The signaling
   extension for this capability exchange is outside the scope of this
   document.

   The intermediate node that is not capable of supporting the IOAM
   functions defined in this document, can simply skip the IOAM
   processing of the MPLS header.

8.  Data Packets with SR-MPLS Header

   Segment Routing (SR) technology leverages the source routing paradigm
   [RFC8660].  A node steers a packet through a controlled set of
   instructions, called segments, by pre-pending the packet with an SR
   header.  In the SR with MPLS data plane (SR-MPLS), the SR header is
   instantiated through a label stack.

   An example of data packet carrying the SR-MPLS header with Path
   Segment Identifier (PSID) [I-D.ietf-spring-mpls-path-segment] with
   IOAM encapsulation is shown in Figure 3.  The Path Segment Identifier
   allows to identify the path associated with the data traffic being
   monitored for IOAM on the decapsulating node.

     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
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |                Label(1)               | TC  |S|      TTL      |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    .                                                               .
    .                                                               .
    .                                                               .
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |                Label(n)               | TC  |S|      TTL      |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |                PSID                   | TC  |S|      TTL      |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |                Packet as shown in Figure 1 or Figure 2        |
    .                                                               .
    +---------------------------------------------------------------+

                 Figure 3: Data Packet with SR-MPLS Header






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9.  Security Considerations

   The security considerations of SR-MPLS are discussed in [RFC8660],
   and the security considerations of IOAM in general are discussed in
   [I-D.ietf-ippm-ioam-data].

   IOAM is considered a "per domain" feature, where one or several
   operators decide on leveraging and configuring IOAM according to
   their needs.  Still, operators need to properly secure the IOAM
   domain to avoid malicious configuration and use, which could include
   injecting malicious IOAM packets into a domain.

10.  IANA Considerations

   IANA maintains the "Special-Purpose Multiprotocol Label Switching
   (MPLS) Label Values" registry (see <https://www.iana.org/assignments/
   mpls-label-values/mpls-label-values.xml>).  IANA is requested to
   allocate IOAM Indicator Label value and IOAM and Flow Indicator value
   from the "Extended Special-Purpose MPLS Label Values" registry:

      +--------+-----------------------------------+---------------+
      |  Value |  Description                      |  Reference    |
      +--------+-----------------------------------+---------------+
      | TBA1   | E2E IOAM Indicator Label          | This document |
      +--------+-----------------------------------+---------------+
      | TBA2   | E2E IOAM and Flow Indicator Label | This document |
      +--------+-----------------------------------+---------------+
      | TBA3   | HbH IOAM Indicator Label          | This document |
      +--------+-----------------------------------+---------------+
      | TBA4   | HbH IOAM and Flow Indicator Label | This document |
      +--------+-----------------------------------+---------------+

11.  References

11.1.  Normative References

   [I-D.ietf-ippm-ioam-data]
              Brockners, F., Bhandari, S., and T. Mizrahi, "Data Fields
              for In-situ OAM", draft-ietf-ippm-ioam-data-10 (work in
              progress), July 2020.

   [I-D.ietf-ippm-ioam-direct-export]
              Song, H., Gafni, B., Zhou, T., Li, Z., Brockners, F.,
              Bhandari, S., Sivakolundu, R., and T. Mizrahi, "In-situ
              OAM Direct Exporting", draft-ietf-ippm-ioam-direct-
              export-01 (work in progress), August 2020.





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   [I-D.ietf-ippm-ioam-flags]
              Mizrahi, T., Brockners, F., Bhandari, S., Sivakolundu, R.,
              Pignataro, C., Kfir, A., Gafni, B., Spiegel, M., and J.
              Lemon, "In-situ OAM Flags", draft-ietf-ippm-ioam-flags-02
              (work in progress), July 2020.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/info/rfc2119>.

   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <https://www.rfc-editor.org/info/rfc8174>.

   [RFC8660]  Bashandy, A., Ed., Filsfils, C., Ed., Previdi, S.,
              Decraene, B., Litkowski, S., and R. Shakir, "Segment
              Routing with the MPLS Data Plane", RFC 8660,
              DOI 10.17487/RFC8660, December 2019,
              <https://www.rfc-editor.org/info/rfc8660>.

   [RFC8664]  Sivabalan, S., Filsfils, C., Tantsura, J., Henderickx, W.,
              and J. Hardwick, "Path Computation Element Communication
              Protocol (PCEP) Extensions for Segment Routing", RFC 8664,
              DOI 10.17487/RFC8664, December 2019,
              <https://www.rfc-editor.org/info/rfc8664>.

11.2.  Informative References

   [I-D.ietf-mpls-spl-terminology]
              Andersson, L., Kompella, K., and A. Farrel, "Special
              Purpose Label terminology", draft-ietf-mpls-spl-
              terminology-03 (work in progress), August 2020.

   [I-D.ietf-spring-mpls-path-segment]
              Cheng, W., Li, H., Chen, M., Gandhi, R., and R. Zigler,
              "Path Segment in MPLS Based Segment Routing Network",
              draft-ietf-spring-mpls-path-segment-02 (work in progress),
              February 2020.

   [RFC4385]  Bryant, S., Swallow, G., Martini, L., and D. McPherson,
              "Pseudowire Emulation Edge-to-Edge (PWE3) Control Word for
              Use over an MPLS PSN", RFC 4385, DOI 10.17487/RFC4385,
              February 2006, <https://www.rfc-editor.org/info/rfc4385>.







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   [RFC4928]  Swallow, G., Bryant, S., and L. Andersson, "Avoiding Equal
              Cost Multipath Treatment in MPLS Networks", BCP 128,
              RFC 4928, DOI 10.17487/RFC4928, June 2007,
              <https://www.rfc-editor.org/info/rfc4928>.

   [RFC6790]  Kompella, K., Drake, J., Amante, S., Henderickx, W., and
              L. Yong, "The Use of Entropy Labels in MPLS Forwarding",
              RFC 6790, DOI 10.17487/RFC6790, November 2012,
              <https://www.rfc-editor.org/info/rfc6790>.

Acknowledgements

   The authors would like to thank Patrick Khordoc, Shwetha Bhandari and
   Vengada Prasad Govindan for the discussions on IOAM.  The authors
   would also like to thank Tarek Saad, Loa Andersson, Greg Mirsky, and
   Cheng Li for providing many useful comments.

Contributors

   Sagar Soni
   Cisco Systems, Inc.

   Email: sagsoni@cisco.com



Authors' Addresses

   Rakesh Gandhi (editor)
   Cisco Systems, Inc.
   Canada

   Email: rgandhi@cisco.com


   Zafar Ali
   Cisco Systems, Inc.

   Email: zali@cisco.com


   Clarence Filsfils
   Cisco Systems, Inc.
   Belgium

   Email: cf@cisco.com





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   Frank Brockners
   Cisco Systems, Inc.
   Hansaallee 249, 3rd Floor
   DUESSELDORF, NORDRHEIN-WESTFALEN  40549
   Germany

   Email: fbrockne@cisco.com


   Bin Wen
   Comcast

   Email: Bin_Wen@cable.comcast.com


   Voitek Kozak
   Comcast

   Email: Voitek_Kozak@comcast.com
































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