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IPPM                                                        T. Zhou, Ed.
Internet-Draft                                               J. Guichard
Intended status: Standards Track                                  Huawei
Expires: September 5, 2018                                  F. Brockners
                                                             S. Raghavan
                                                           Cisco Systems
                                                           March 4, 2018


                   A YANG Data Model for In-Situ OAM
                      draft-zhou-ippm-ioam-yang-00

Abstract

   In-situ Operations, Administration, and Maintenance (IOAM) records
   operational and telemetry information in user packets while the
   packets traverse a path between two points in the network.  This
   document defines a YANG module for the IOAM function.

Requirements 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 RFC 2119 [RFC2119].

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
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at https://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 September 5, 2018.

Copyright Notice

   Copyright (c) 2018 IETF Trust and the persons identified as the
   document authors.  All rights reserved.





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   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
   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
     1.1.  Tree Diagrams . . . . . . . . . . . . . . . . . . . . . .   3
   2.  Design of the IOAM YANG Data Model  . . . . . . . . . . . . .   3
     2.1.  Profiles  . . . . . . . . . . . . . . . . . . . . . . . .   3
     2.2.  Preallocated Tracing Profile  . . . . . . . . . . . . . .   4
     2.3.  Incremental Tracing Profile . . . . . . . . . . . . . . .   5
     2.4.  Proof of Transit Profile  . . . . . . . . . . . . . . . .   5
     2.5.  Edge to Edge Profile  . . . . . . . . . . . . . . . . . .   5
   3.  IOAM YANG Module  . . . . . . . . . . . . . . . . . . . . . .   6
   4.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  15
   5.  Security Considerations . . . . . . . . . . . . . . . . . . .  15
   6.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  15
   7.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  15
     7.1.  Normative References  . . . . . . . . . . . . . . . . . .  15
     7.2.  Informative References  . . . . . . . . . . . . . . . . .  16
   Appendix A.  Examples . . . . . . . . . . . . . . . . . . . . . .  17
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  17

1.  Introduction

   In-situ Operations, Administration, and Maintenance (IOAM)
   [I-D.ietf-ippm-ioam-data] records OAM information within user packets
   while the packets traverse a network.  The data types and data
   formats for IOAM data records have been defined in
   [I-D.ietf-ippm-ioam-data].  The IOAM data can be embedded in many
   protocol encapsulations such as Network Services Header, Segment
   Routing, and IPv6 [I-D.brockners-inband-oam-transport].

   This document defines a data model for IOAM capabilities using the
   YANG data modeling language [RFC6020][RFC7950].  This YANG model
   supports all the three categories of IOAM data, which are Tracing
   Option, Proof of Transit Option, and Edge-to-Edge Option.







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1.1.  Tree Diagrams

   The meaning of the symbols in these diagrams is as follows:

   o  Brackets "[" and "]" enclose list keys.

   o  Curly braces "{" and "}" contain names of optional features that
      make the corresponding node conditional.

   o  Abbreviations before data node names: "rw" means configuration
      (read-write), "ro" state data (read-only).

   o  Symbols after data node names: "?" means an optional node, "!" a
      container with presence, and "*" denotes a "list" or "leaf-list".

   o  Parentheses enclose choice and case nodes, and case nodes are also
      marked with a colon (":").

   o  Ellipsis ("...") stands for contents of subtrees that are not
      shown.

2.  Design of the IOAM YANG Data Model

2.1.  Profiles

   The IOAM model is organized as list of profiles as shown in the
   following figure.  Each profile associates with one flow and the
   corresponding IOAM information.

      +--rw ioam
         +--rw ioam-profiles
            +--rw enabled?        boolean
            +--rw ioam-profile* [profile-name]
               +--rw profile-name                    string
               +--rw filter
               |  +--rw filter-type?   ioam-filter-type
               |  +--rw acl-name?      -> /acl:access-lists/acl/name
               +--rw protocol-type?                  ioam-protocol-type
               +--rw incremental-tracing-profile
               |  ...
               +--rw preallocated-tracing-profile
               |  ...
               +--rw pot-profile
               |  ...
               +--rw e2e-profile
                  ...





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   The "filter" is used to identify a flow, where the IOAM profile can
   apply.  There may be multiple filter types.  ACL is the default one.

   The IOAM data can be encapsulated into multiple protocols, e.g.,
   IPv6, Geneve,VxLAN-GPE.  The "protocol-type" is used to indicate
   where the IOAM is applied.  For example, if the protocol-type is
   IPv6, the IOAM ingress node will encapsulate the associated flow with
   the IPv6-IOAM [I-D.brockners-inband-oam-transport] format.

   IOAM data includes three usage options with four types data, i.e.,
   incremental tracing data, preallocated tracing data, prove of transit
   data and end to end data.  In practice, multiple IOAM data types can
   be encapsulated into the same IOAM header.

2.2.  Preallocated Tracing Profile

   The IOAM tracing data is expected to be collected at every node that
   a packet traverses to ensure visibility into the entire path a packet
   takes within an IOAM domain.  The preallocated tracing option will
   create pre-allocated space for each node to populate its information
   . The "preallocated-tracing-profile" contains the detailed
   information for the preallocated tracing data.  It's only valid when
   the "enable-preallocated-tracing-option" is set to true.  The
   information includes:

   o  enabled: indicates whether the preallocated tracing profile is
      enabled.

   o  node-action: indicates the operation (e.g., encapsulate IOAM
      header, transit the IOAM data, or decapsulate IOAM header) applied
      to the dedicated flow.

   o  trace-type: indicates the per-hop data to be captured by the IOAM
      enabled nodes and included in the node data list.

   o  Loopback mode is used to send a copy of a packet back towards the
      source.

                +--rw preallocated-tracing-profile
                   +--rw enabled?                boolean
                   +--rw node-action?            ioam-node-action
                   +--rw trace-type?             ioam-trace-types
                   +--rw enable-loopback-mode?   boolean








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2.3.  Incremental Tracing Profile

   The incremental tracing option contains a variable node data fields
   where each node allocates and pushes its node data immediately
   following the option header.  The "incremental-tracing-profile"
   contains the detailed information for the incremental tracing data.
   It's only valid when the "enable-incremental-tracing-option" is set
   to true.  The detailed information is the same as the Preallocated
   Tracing Profile, but with one more variable, "max-length", which
   restricts the length of the IOAM header.

                +--rw incremental-tracing-profile
                   +--rw enabled?                boolean
                   +--rw node-action?            ioam-node-action
                   +--rw trace-type?             ioam-trace-types
                   +--rw enable-loopback-mode?   boolean
                   +--rw max-length?             uint32

2.4.  Proof of Transit Profile

   The IOAM Proof of Transit data is to support the path or service
   function chain verification use cases.  The "pot-profile" contains
   the detailed information for the prove of transit data.  It's only
   valid when the "enable-pot-option" is set to true.  The detailed
   information are described in [I-D.brockners-proof-of-transit].

                +--rw pot-profile
                   +--rw enabled?                boolean
                   +--rw active-profile-index?   pot:profile-index-range
                   +--rw pot-profile-list* [pot-profile-index]
                      +--rw pot-profile-index    profile-index-range
                      +--rw prime-number         uint64
                      +--rw secret-share         uint64
                      +--rw public-polynomial    uint64
                      +--rw lpc                  uint64
                      +--rw validator?           boolean
                      +--rw validator-key?       uint64
                      +--rw bitmask?             uint64

2.5.  Edge to Edge Profile

   The IOAM edge to edge option is to carry data that is added by the
   IOAM encapsulating node and interpreted by IOAM decapsulating node.
   The "e2e-profile" contains the detailed information for the edge to
   edge data.  It's only valid when the "enable-e2e-option" is set to
   true.  The detailed information includes:

   o  enabled: indicates whether the edge to edge profile is enabled.



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   o  node-action is the same semantic as in Section 2.2.

   o  e2e-type indicates data to be carried from the ingress IOAM node
      to the egress IOAM node.

                +--rw e2e-profile
                   +--rw enabled?                boolean
                   +--rw node-action?   ioam-node-action
                   +--rw e2e-type?      ioam-e2e-types

3.  IOAM YANG Module

  <CODE BEGINS> file "ietf-ioam@2018-03-04.yang"
  module ietf-ioam {
    yang-version 1.1;
    namespace "urn:ietf:params:xml:ns:yang:ietf-ioam";
    prefix "ioam";

    import ietf-pot-profile {
      prefix "pot";
    }

    import ietf-access-control-list {
      prefix "acl";
    }

    organization
      "IETF IPPM (IP Performance Metrics) Working Group";

    contact
      "WG Web: <http://tools.ietf.org/wg/ippm>
       WG List: <ippm@ietf.org>
       Editor: zhoutianran@huawei.com";

    description
      "This YANG module specifies a vendor-independent data
       model for the in Situ OAM (iOAM).";

    revision 2018-03-04 {
      description "Initial revision.";
      reference "draft-song-ippm-ioam-yang";
    }

    identity base-filter {
      description
        "Base identity to represent a filter. A filter is used to
        specify the flow to apply the iOAM profile. ";
    }



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    identity acl-filter {
      base base-filter;
      description
        "Apply ACL rule to specify the flow.";
    }

    identity base-protocol {
      description
        "Base identity to represent the carrier protocol. It's used to
         indicate what layer and protocol the iOAM data is embedded.";
    }

    identity ipv6-protocol {
      base base-protocol;
      description
        "The described iOAM data is embedded in ipv6 protocol.";
    }

    identity base-node-action {
      description
        "Base identity to represent the node actions. It's used to
         indicate what action the node will take.";
    }

    identity encapsulate {
      base base-node-action;
      description
        "indicate the node is to encapsulate the iOAM packet";
    }

    identity transit {
      base base-node-action;
      description
        "indicate the node is to transit the iOAM packet";
    }

    identity decapsulate {
      base base-node-action;
      description
        "indicate the node is to decapsulate the iOAM packet";
    }

    typedef ioam-filter-type {
      type identityref {
        base base-filter;
      }
      description
        "Specifies a known type of filter.";



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    }

    typedef ioam-protocol-type {
      type identityref {
        base base-protocol;
      }
      description
        "Specifies a known type of carrier protocol for the iOAM data.";
    }

    typedef ioam-node-action {
      type identityref {
        base base-node-action;
      }
      description
        "Specifies a known type of node action.";
    }

    typedef ioam-trace-types {
      type bits {
        bit ioam-hop-lim-node-id {
          position 0;
          description
            "When set indicates presence of Hop_Lim and node_id in the
            node data.";
        }
        bit ioam-if-id {
          position 1;
          description
            "When set indicates presence of ingress_if_id and
            egress_if_id in the node data.";
        }
        bit ioam-timestamp-seconds {
          position 2;
          description
            "When set indicates presence of time stamp seconds in the
            node data.";
        }
        bit ioam-timestamp-nanoseconds {
          position 3;
          description
            "When set indicates presence of time stamp nanoseconds in
            the node data.";
        }
        bit ioam-transit-delay {
          position 4;
          description
            "When set indicates presence of transit delay in the node



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            data.";
        }
        bit ioam-app-data {
          position 5;
          description
            "When set indicates presence of app_data in the node data.";
        }
        bit ioam-queue-depth {
          position 6;
          description
            "When set indicates presence of queue depth in the node
            data.";
        }
        bit ioam-opaque-state-snapshot {
          position 7;
          description
            "When set indicates presence of variable length Opaque
            State Snapshot field.";
        }
        bit ioam-hop-lim-node-id-wide {
          position 8;
          description
            "When set indicates presence of Hop_Lim and node_id wide
             in the node data.";
        }
        bit ioam-if-id-wide {
          position 9;
          description
            "When set indicates presence of ingress_if_id and
            egress_if_id wide in the node data.";
        }
        bit app-data-wide {
          position 10;
          description
            "When set indicates presence of app_data wide in the node
            data.";
        }
      }
      description
        "A 16-bit identifier which specifies which data types are used
         in this node data list.";
    }

    typedef ioam-pot-types {
      type bits {
        bit ioam-bytes-16 {
          position 0;
          description



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            "POT data is a 16 Octet field";
        }
      }
      description
        "7-bit identifier of a particular POT variant that dictates
          the POT data that is included.";
    }

    typedef ioam-e2e-types {
      type bits {
        bit ioam-seq-num {
          position 0;
          description
            "A 64-bit sequence number added to a specific tube which is
             used to identify packet loss and reordering for that
             tube.";
        }
      }
      description
        "8-bit identifier of a particular in situ OAM E2E variant.";
    }

    grouping ioam-filter {
      description "A grouping for iOAM filter definition";

      leaf filter-type {
        type ioam-filter-type;
        description "filter type";
      }

      leaf acl-name {
        when "../filter-type = 'acl-filter'";
        type leafref {
          path "/acl:access-lists/acl:acl/acl:name";
        }
        description "Access Control List name.";
      }
    }

    grouping ioam-incremental-tracing-profile {
      description
        "A grouping for incremental tracing profile.";

      leaf node-action {
        type ioam-node-action;
        description "node action";
      }




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      leaf trace-type {
        when "../node-action = 'encapsulate'";
        type ioam-trace-types;
        description
          "The trace type is only defined at the encapsulation node.";
      }

      leaf enable-loopback-mode {
        when "../node-action = 'encapsulate'";
        type boolean;
        default false;
        description
          "Loopback mode is used to send a copy of a packet back towards
          the source. The loopback mode is only defined at the
          encapsulation node.";
      }

      leaf max-length {
        when "../node-action = 'encapsulate'";
        type uint32;
        description
          "This field specifies the maximum length of the node data list
          in octets. The max-length is only defined at the
          encapsulation node. And it's only used for the incremental
          tracing mode.";
      }
    }

    grouping ioam-preallocated-tracing-profile {
      description
        "A grouping for incremental tracing profile.";

      leaf node-action {
        type ioam-node-action;
        description "node action";
      }

      leaf trace-type {
        when "../node-action = 'encapsulate'";
        type ioam-trace-types;
        description
          "The trace type is only defined at the encapsulation node.";
      }

      leaf enable-loopback-mode {
        when "../node-action = 'encapsulate'";
        type boolean;
        default false;



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        description
          "Loopback mode is used to send a copy of a packet back towards
          the source. The loopback mode is only defined at the
          encapsulation node.";
      }
    }

    grouping ioam-e2e-profile {
      description
        "A grouping for tracing profile.";

      leaf node-action {
        type ioam-node-action;
        description
          "indicate how the node act for this profile";
      }

      leaf e2e-type {
        when "../node-action = 'encapsulate'";
        type ioam-e2e-types;
        description
          "The e2e type is only defined at the encapsulation node.";
      }
    }

    grouping ioam-admin-config {
      description
        "IOAM top-level administrative configuration.";

        leaf enabled {
        type boolean;
        default false;
        description
          "When true, IOAM configuration is enabled for the system.";
      }
    }

    container ioam {
      description "iOAM top level container";

      container ioam-profiles {
        description
          "Contains a list of iOAM profiles.";

        uses ioam-admin-config;

        list ioam-profile {
          key "profile-name";



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          ordered-by user;
          description
            "A list of iOAM profiles that configured on the node.";

          leaf profile-name {
            type string;
            description
              "Unique identifier for each iOAM profile";
          }

          container filter {
            uses ioam-filter;
            description
              "The filter which is used to indicate the flow to apply
              iOAM.";
          }

          leaf protocol-type {
            type ioam-protocol-type;
            description
              "This item is used to indicate the carrier protocol where
              the iOAM is applied.";
          }

          container incremental-tracing-profile {
            description
              "describe the profile for incremental tracing option";

            leaf enabled {
              type boolean;
              default false;
              description
                "When true, apply incremental tracing option to the
                 specified flow identified by the filter.";
            }

            uses ioam-incremental-tracing-profile;
          }

          container preallocated-tracing-profile {
            description
              "describe the profile for preallocated tracing option";

            leaf enabled {
              type boolean;
              default false;
              description
                "When true, apply preallocated tracing option to the



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                 specified flow identified by the following filter.";
            }

            uses ioam-preallocated-tracing-profile;
          }

          container pot-profile {
            description
              "describe the profile for pot option";

            leaf enabled {
              type boolean;
              default false;
              description
                "When true, apply Proof of Transit option to the
                 specified flow identified by the following filter.";
            }

            leaf active-profile-index {
            type pot:profile-index-range;
            description
              "Proof of transit profile index that is currently
               active. Will be set in the first hop of the path
               or chain. Other nodes will not use this field.";
            }

            uses pot:pot-profile;
          }

          container e2e-profile {
            description
              "describe the profile for e2e option";

            leaf enabled {
              type boolean;
              default false;
              description
                "When true, apply End to end option to the
                 specified flow identified by the following filter.";
            }

            uses ioam-e2e-profile;
          }
        }
      }
    }
  }
  <CODE ENDS>



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4.  IANA Considerations

   RFC Ed.: In this section, replace all occurrences of 'XXXX' with the
   actual RFC number (and remove this note).

   This document requests IANA to register the following URI in the
   "IETF XML Registry" [RFC3688]:

               URI: urn:ietf:params:xml:ns:yang:ietf-ioam
               Registrant Contact: The IESG.
               XML: N/A; the requested URI is an XML namespace.

   This document requests IANA to register the following YANG module in
   the "YANG Module Names" registry [RFC7950].

               name: ietf-ioam
               namespace: urn:ietf:params:xml:ns:yang:ietf-ioam
               prefix: nat
               reference: RFC XXXX

5.  Security Considerations

   The YANG module defined in this memo is designed to be accessed via
   the NETCONF protocol [RFC6241].  The lowest NETCONF layer is the
   secure transport layer and the support of SSH is mandatory to
   implement secure transport[RFC6242].  The NETCONF access control
   model [RFC6536] provides means to restrict access by some users to a
   pre-configured subset of all available NETCONF protocol operations
   and data.  All data nodes defined in the YANG module which can be
   created, modified and deleted (i.e., config true, which is the
   default).  These data nodes are considered sensitive.  Write
   operations (e.g., edit-config) applied to these data nodes without
   proper protection can negatively affect network operations.

6.  Acknowledgements

7.  References

7.1.  Normative References

   [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>.

   [RFC3688]  Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
              DOI 10.17487/RFC3688, January 2004,
              <https://www.rfc-editor.org/info/rfc3688>.



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   [RFC6020]  Bjorklund, M., Ed., "YANG - A Data Modeling Language for
              the Network Configuration Protocol (NETCONF)", RFC 6020,
              DOI 10.17487/RFC6020, October 2010,
              <https://www.rfc-editor.org/info/rfc6020>.

   [RFC6241]  Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,
              and A. Bierman, Ed., "Network Configuration Protocol
              (NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011,
              <https://www.rfc-editor.org/info/rfc6241>.

   [RFC6242]  Wasserman, M., "Using the NETCONF Protocol over Secure
              Shell (SSH)", RFC 6242, DOI 10.17487/RFC6242, June 2011,
              <https://www.rfc-editor.org/info/rfc6242>.

   [RFC6536]  Bierman, A. and M. Bjorklund, "Network Configuration
              Protocol (NETCONF) Access Control Model", RFC 6536,
              DOI 10.17487/RFC6536, March 2012,
              <https://www.rfc-editor.org/info/rfc6536>.

   [RFC7950]  Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
              RFC 7950, DOI 10.17487/RFC7950, August 2016,
              <https://www.rfc-editor.org/info/rfc7950>.

7.2.  Informative References

   [I-D.brockners-inband-oam-transport]
              Brockners, F., Bhandari, S., Govindan, V., Pignataro, C.,
              Gredler, H., Leddy, J., Youell, S., Mizrahi, T., Mozes,
              D., Lapukhov, P., and R. Chang, "Encapsulations for In-
              situ OAM Data", draft-brockners-inband-oam-transport-05
              (work in progress), July 2017.

   [I-D.brockners-proof-of-transit]
              Brockners, F., Bhandari, S., Dara, S., Pignataro, C.,
              Leddy, J., Youell, S., Mozes, D., and T. Mizrahi, "Proof
              of Transit", draft-brockners-proof-of-transit-04 (work in
              progress), October 2017.

   [I-D.ietf-ippm-ioam-data]
              Brockners, F., Bhandari, S., Pignataro, C., Gredler, H.,
              Leddy, J., Youell, S., Mizrahi, T., Mozes, D., Lapukhov,
              P., Chang, R., and d. daniel.bernier@bell.ca, "Data Fields
              for In-situ OAM", draft-ietf-ippm-ioam-data-01 (work in
              progress), October 2017.







Zhou, Ed., et al.       Expires September 5, 2018              [Page 16]


Internet-Draft             YANG Model for IOAM                March 2018


Appendix A.  Examples

   TBD

Authors' Addresses

   Tianran Zhou
   Huawei
   156 Beiqing Rd.
   Beijing  100095
   China

   Phone: 15810236238
   Email: zhoutianran@huawei.com


   Jim Guichard
   Huawei
   USA

   Email: james.n.guichard@huawei.com


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

   Email: fbrockne@cisco.com


   Srihari Raghavan
   Cisco Systems
   Tril Infopark Sez, Ramanujan IT City
   Neville Block, 2nd floor, Old Mahabalipuram Road
   Chennai, Tamil Nadu  600113
   India

   Email: srihari@cisco.com











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