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Using Application Identification in Services Function Chaining Metadata
draft-penno-sfc-appid-02

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This is an older version of an Internet-Draft whose latest revision state is "Expired".
Authors Reinaldo Penno , Benoît Claise , Carlos Pignataro , Christophe Fontaine
Last updated 2015-12-01
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draft-penno-sfc-appid-02
SFC Netmod                                                      R. Penno
Internet-Draft                                                 B. Claise
Intended status: Standards Track                            C. Pignataro
Expires: June 3, 2016                                              Cisco
                                                             C. Fontaine
                                                                  Qosmos
                                                        December 1, 2015

Using Application Identification in Services Function Chaining Metadata
                        draft-penno-sfc-appid-02

Abstract

   This document proposes to use the structured application information
   in the service function chaining metadata, and specifies a YANG model
   for the configuration of the application registry.

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 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 June 3, 2016.

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
   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

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   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Open Issues . . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
     2.1.  Terminology . . . . . . . . . . . . . . . . . . . . . . .   3
     2.2.  Tree Diagrams . . . . . . . . . . . . . . . . . . . . . .   3
   3.  Application Information Structure . . . . . . . . . . . . . .   4
   4.  Application Information Yang Model  . . . . . . . . . . . . .   5
     4.1.  Module Structure  . . . . . . . . . . . . . . . . . . . .   5
     4.2.  Application Information Configuration Module  . . . . . .   6
   5.  Service Function Chaining Metadata  . . . . . . . . . . . . .  11
   6.  Relationship to existing YANG Modules . . . . . . . . . . . .  11
   7.  Expected Usage  . . . . . . . . . . . . . . . . . . . . . . .  12
   8.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  12
   9.  Security Considerations . . . . . . . . . . . . . . . . . . .  12
   10. Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  12
   11. Changes . . . . . . . . . . . . . . . . . . . . . . . . . . .  12
   12. Informative References  . . . . . . . . . . . . . . . . . . .  12
   Appendix A.  Application Information Examples . . . . . . . . . .  14
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  15

1.  Open Issues

   1.  Corrected all the pyang compilation errors, except:
       bclaise@bclaise-VirtualBox:/media/sf_ubuntu-share/temp$ pyang
       --ietf ipfix-application-information@2015-04-28.yang ipfix-
       application-information@2015-04-28.yang:1: warning: IETF rule
       (RFC 6087: 4.9): too many top-level data nodes: class-id-
       dictionary, application-id-dictionary

   2.  Any reasons why those attributes are not modeled as boolean: P2P-
       technology, tunnel-technology, encrypted?

   3.  The connection between the YANG Model in this document and
       [I-D.penno-sfc-yang] must be explained

2.  Introduction

   The "Cisco Systems Export of Application Information in IP Flow
   Information Export (IPFIX) [RFC6759] specifies an extension to the
   IPFIX information model [RFC7012] to export application information.
   This IPFIX information element is registered as the identifier 95 in
   the IPFIX registry [IANA-IPFIX].  Applications could be identified at
   different OSI layers, from layer 2 to layer 7.  For example, the Link
   Layer Distribution Protocol [LLDP] can be identified in layer 2, ICMP

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   can be identified in layer 3 [IANA-PROTO], HTTP can be identified in
   layer 4 [IANA-PORTS], and Webex can be identified in layer 7.
   However, the layer 7 application registry values are out of scope of
   [RFC6759]

   This document purposes the use of IPFIX [RFC7011] application
   information to be carried in the NSH context metadata of a MDType-1
   packet.  The information in the metadata will be the result of packet
   processing done by a firewall, Intrusion Protection Service, Deep
   Packet Inspection, amongst others.  These are defined as providers of
   application information.

   The consumers of application information are Service Functions that
   apply policy provides application statistics based on the metadata
   contained in the packet.

2.1.  Terminology

   The reader should be familiar with the terms contained in the
   following documents:

   o  Section 1.4 of the "Service Function Chaining (SFC) Architecture"
      [RFC7665]

   o  Section 2.1 of the "Network Service Header" [I-D.ietf-sfc-nsh]

   o  The "Generic Protocol Extension for VXLAN"
      [I-D.ietf-nvo3-vxlan-gpe]

   o  Sections 3 and 3.1 of "Cisco Systems Export of Application
      Information in IP Flow Information Export (IPFIX)" [RFC6759]

2.2.  Tree Diagrams

   A simplified graphical representation of the data model is used in
   this document.  The meaning of the symbols in these diagrams is as
   follows:

   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), "-x" RPC operations,
      and "-n" notifications.

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   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.

3.  Application Information Structure

   The application information data structure can be seen in Figure 1.
   It was extracted and adapted from [RFC6759].

      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
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     | Class. Eng. ID|    Zero-valued upper-bits ... Selector ID     |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

             Figure 1: Application Identification Data Format

   Table 1 displays the currently allocated Classification Engine IDs,
   including their name and value, as well as their corresponding
   Selector ID default length.

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   +---------------------+--------------------+------------------------+
   |    Classification   |   Classification   |  Selector ID default   |
   |   Engine ID Value   |   Engine ID Name   |   length (in octets)   |
   +---------------------+--------------------+------------------------+
   |          1          |      IANA-L3       |           1            |
   +---------------------+--------------------+------------------------+
   |          2          |      PANA-L3       |           1            |
   +---------------------+--------------------+------------------------+
   |          3          |      IANA-L4       |           2            |
   +---------------------+--------------------+------------------------+
   |          4          |      PANA-L4       |           2            |
   +---------------------+--------------------+------------------------+
   |          6          |    USER-Defined    |           3            |
   +---------------------+--------------------+------------------------+
   |          12         |      PANA-L2       |           5            |
   +---------------------+--------------------+------------------------+
   |          13         |      PANA-L7       |           3            |
   +---------------------+--------------------+------------------------+
   |          18         |     ETHERTYPE      |           2            |
   +---------------------+--------------------+------------------------+
   |          19         |        LLC         |           1            |
   +---------------------+--------------------+------------------------+
   |          20         |    PANA-L7-PEN     |         3 (*)          |
   +---------------------+--------------------+------------------------+

                Table 1: Existing Classification Engine IDs

   Where:

      "PANA = Proprietary Assigned Number Authority".  In other words,
      an enterprise specific version of IANA for internal IDs.

      PEN = Private Enterprise Number

      (*) There are an extra 4 bytes for the PEN.  However, the PEN is
      not considered part of the Selector ID.

4.  Application Information Yang Model

4.1.  Module Structure

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   module: ipfix-application-information
      +--rw class-id-dictionary
      |  +--rw class-id* [name]
      |     +--rw id?            uint8
      |     +--rw name           string
      |     +--rw description?   string
      +--rw application-id-dictionary
         +--rw application-id* [application-name]
            +--rw class-id      -> /class-id-dictionary/class-id/id
            +--rw pen                              uint32
            +--rw selector-id                      uint32
            +--rw application-name                 string
            +--rw application-description?         string
            +--rw application-category-name?       string
            +--rw application-sub-category-name?   string
            +--rw application-group-name?          string

4.2.  Application Information Configuration Module

   <CODE BEGINS> file "ipfix-application-information@2015-04-28.yang"

   module ipfix-application-information {
     yang-version 1;

     namespace "urn:ietf:params:xml:ns:yang:"
               + "ipfix-application-information";

     prefix ipfix-app-info;

     organization
        "IETF SFC (Service Function Chaining) Working Group";

     contact
         "Editor: Christophe Fontaine
          christophe.fontaine@qosmos.com

          Editor: Reinaldo Penno
          rapenno@gmail.com";

     description
        "This module contains a collection of YANG definitions for
         the configuration of application ids.

         Copyright (c) 2015 IETF Trust and the persons identified as
         authors of the code.  All rights reserved.

         Redistribution and use in source and binary forms, with or
         without modification, is permitted pursuant to, and subject

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         to the license terms contained in, the Simplified BSD License
         set forth in Section 4.c of the IETF Trust's Legal Provisions
         Relating to IETF Documents
         (http://trustee.ietf.org/license-info).";

     revision 2015-04-28 {
       description "Initial revision";
       reference
          "draft-penno-sfc-appid : Using Application Identification in
           Services Function Chaining Metadata";
     }

     /*
      * Typedefs
      */

     typedef application-id-ref {
         type leafref {
             path "/ipfix-app-info:application-id-dictionary/"
             + "ipfix-app-info:application-id/ipfix-app-info"
             + ":application-name";
         }
         description "This type is used by data models that need
                      to reference an application-id";
     }

     typedef classification-engine-id {
       type enumeration {
         enum "IANA-L3" {
           value 1;
           description
             "IANA-L3";
         }
         enum "PANA-L3" {
           value 2;
           description
             "PANA-L3";
         }
         enum "IANA-L4" {
           value 3;
           description
             "IANA-L4";
         }
         enum "PANA-L4" {
           value 4;
           description
             "PANA-L4";
         }

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         enum "USER-Defined" {
           value 6;
           description
             "USER-Defined";
         }
         enum "PANA-L2" {
           value 12;
           description
             "PANA-L2";
         }
         enum "PANA-L7" {
           value 13;
           description
             "PANA-L7";
         }
         enum "ETHERTYPE" {
           value 18;
           description
             "ETHERTYPE";
         }
         enum "LLC" {
           value 19;
           description
             "LLC";
         }
         enum "PANA-L7-PEN" {
           value 20;
           description
             "PANA-L7-PEN";
         }
       }
       description
         "The definitions for Classification engine ID names.";
       reference
          "RFC 6759: Cisco Systems Export of Application Information
           in IP Flow Information Export (IPFIX)";
     }
     /*
      * Configuration data nodes
      */

     container class-id-dictionary {
         description "Dictionary for classification ids";
         list class-id {
             key "name";
             unique "id";
             leaf id {
                 type uint8;

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                 description "Classification identifier";
             }
             leaf name {
                 type string;
                 description "classification Engine name";
             }
             leaf description {
                 type string;
                 description "Description of the class-id";
             }
             description "A list of all classification ids";
         }
     }

     container application-id-dictionary {
         description "Dictionary for application ids";
         list application-id {
             key "application-name";
             unique "class-id pen selector-id";
             leaf class-id {
                 type leafref {
                     path "/ipfix-app-info:class-id-dictionary/"
                          + "ipfix-app-info:class-id/ipfix-app-info:id";
                 }
                 mandatory true;
                 description "Application Name";
             }
             leaf pen {
                 type uint32;
                 mandatory true;
                 description "Private Entreprise Number, only relevant
                              when used with appropriate class-id.
                              Set to 0 when not used.";
             }
             leaf selector-id {
                 type uint32 {
                     range "0..16777216";
                 }
                 mandatory true;
                 description "Selector identifier";
             }
             leaf application-name {
                 type string;
                 mandatory true;
                 description "The name of the application";
             }
             leaf application-description {
                 type string;

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                 description "The description of the application";
             }
             leaf application-category-name {
                 type string;
                 description "An attribute that provides a first-
                              level categorization for each
                              Application ID.  Examples include
                              browsing, email, file-sharing,
                              gaming, instant messaging, voice-
                              and-video, etc.
                              The category attribute is encoded by
                              the application-category-name
                              Information Element";
             }
             leaf application-sub-category-name {
                 type string;
                 description "An attribute that provides a second-
                              level categorization for each
                              Application ID.  Examples include
                              backup-systems, client-server,
                              database, routing-protocol, etc.
                              The sub-category attribute is
                              encoded by the
                              application-sub-category-name
                              Information Element";
             }
             leaf application-group-name {
                 type string;
                 description "An attribute that groups multiple
                              Application IDs that belong to the
                              same networking application.  For
                              example, the ftp-group contains
                              ftp-data (port 20), ftp (port 20),
                              ni-ftp (port 47), sftp (port 115),
                              bftp (port 152), ftp-agent(port
                              574), ftps-data (port 989).  The
                              application-group attribute is
                              encoded by the application-group-name
                              Information Element";
              }
             description "A list of all applications";
         }
     }
   }

   <CODE ENDS>

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5.  Service Function Chaining Metadata

   When a Deep Packet Inspection (DPI), Firewall or any other Service
   Function (SF) that can identify applications want to convey this
   knowledge to other SFs it encoded in the format discussed earlier and
   add to the context metadata.  The Example in Figure 2 shows the
   encoding of the SNMP application.

      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
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |       3       |        0      |              161              |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                  Network Shared Context                       |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                  Service Platform Context                     |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                  Service Shared Context                       |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

       Figure 2: Example of Metadata Including the SNMP Application
                              Identification

   In this example, the Classification Engine IDs of 3 indicates "IANA-
   L4", and 161 is the well-known port number for SNMP (with its upper
   bits zero-valued).

   Other Services Functions that need application information associated
   with a packet or flow can look at this metadata and easily find out
   its value.

6.  Relationship to existing YANG Modules

   [RFC6728] specifies a data model for the IP Flow Information Export
   (IPFIX) and Packet Sampling (PSAMP) protocols.  It is for configuring
   and monitoring Selection Processes, Caches, Exporting Processes, and
   Collecting Processes of IPFIX- and PSAMP-compliant Monitoring Devices
   using the Network Configuration Protocol (NETCONF).  The data model
   is defined using UML (Unified Modeling Language) class diagrams and
   formally specified using YANG.

   The YANG model is this document allows the configuration of the
   application id IPFIX information elements (ieId), which in turn, may
   be used in a template definition (TemplateId).

   [I-D.penno-sfc-yang] To be done

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7.  Expected Usage

   Devices or controllers will download the [ETHERTYPE], [IANA-PROTO]
   and [IANA-PORTS] from the appropriate URIs.  However, the
   configuration of the applications is required for applications not
   registered in an industry-wide agreed-upon registry.  In this case,
   the Proprietary Assigned Number Authority (PANA) registries (PANA-L2,
   PANA-L3, PANA-L4, PANA-L7), or the User-Defined registry, must be
   used to identify new application.

   Furthermore, the following attributes are statically assigned per
   Application ID, and needs to be configured: category, sub-category,
   application-group.

8.  IANA Considerations

   TBD

9.  Security Considerations

   TODO: Update with privacy and security considerations, as requested
   in Prague IETF93.

10.  Acknowledgements

11.  Changes

12.  Informative References

   [ETHERTYPE]
              "ETHERTYPE", 1984,
              <http://standards.ieee.org/develop/regauth/thertype/
              eth.txt>.

   [I-D.ietf-nvo3-vxlan-gpe]
              Quinn, P., Manur, R., Kreeger, L., Lewis, D., Maino, F.,
              Smith, M., Agarwal, P., Yong, L., Xu, X., Elzur, U., Garg,
              P., and D. Melman, "Generic Protocol Extension for VXLAN",
              draft-ietf-nvo3-vxlan-gpe-00 (work in progress), May 2015.

   [I-D.ietf-sfc-nsh]
              Quinn, P. and U. Elzur, "Network Service Header", draft-
              ietf-sfc-nsh-01 (work in progress), July 2015.

   [I-D.penno-sfc-yang]
              Penno, R., Quinn, P., Zhou, D., and J. Li, "Yang Data
              Model for Service Function Chaining", draft-penno-sfc-
              yang-13 (work in progress), March 2015.

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   [IANA-IPFIX]
              IANA, ""IP Flow Information Export (IPFIX) Entities"",
              2015, <http://www.iana.org/assignments/ipfix/>.

   [IANA-PORTS]
              IANA, "IANA-L4", 1984,
              <http://www.iana.org/assignments/port-numbers>.

   [IANA-PROTO]
              IANA, "IANA-L3", 1984,
              <http://www.iana.org/assignments/protocol-numbers>.

   [LLDP]     IEEE, "Std 802.1AB-2005, "Standard for Local and
              metropolitan area networks - Station and Media Access
              Control Connectivity Discovery", IEEE Std 802.1AB-2005",
              2005, <LLDP>.

   [RFC6728]  Muenz, G., Claise, B., and P. Aitken, "Configuration Data
              Model for the IP Flow Information Export (IPFIX) and
              Packet Sampling (PSAMP) Protocols", RFC 6728, DOI
              10.17487/RFC6728, October 2012,
              <http://www.rfc-editor.org/info/rfc6728>.

   [RFC6759]  Claise, B., Aitken, P., and N. Ben-Dvora, "Cisco Systems
              Export of Application Information in IP Flow Information
              Export (IPFIX)", RFC 6759, DOI 10.17487/RFC6759, November
              2012, <http://www.rfc-editor.org/info/rfc6759>.

   [RFC7011]  Claise, B., Ed., Trammell, B., Ed., and P. Aitken,
              "Specification of the IP Flow Information Export (IPFIX)
              Protocol for the Exchange of Flow Information", STD 77,
              RFC 7011, DOI 10.17487/RFC7011, September 2013,
              <http://www.rfc-editor.org/info/rfc7011>.

   [RFC7012]  Claise, B., Ed. and B. Trammell, Ed., "Information Model
              for IP Flow Information Export (IPFIX)", RFC 7012, DOI
              10.17487/RFC7012, September 2013,
              <http://www.rfc-editor.org/info/rfc7012>.

   [RFC7665]  Halpern, J., Ed. and C. Pignataro, Ed., "Service Function
              Chaining (SFC) Architecture", RFC 7665, DOI 10.17487/
              RFC7665, October 2015,
              <http://www.rfc-editor.org/info/rfc7665>.

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Appendix A.  Application Information Examples

   Below as some examples from [RFC6759]

   (preamble)

6.4. Example 4: Standardized IANA Layer 4 Port

   From the list of Classification Engine IDs in Table 1, the IANA layer
   4 Classification Engine ID (IANA-L4) is 3.  From Table 2 the Selector
   ID length is 2 for the IANA-L4 Engine ID.

   From the list of IANA layer 4 ports (see [IANA-PORTS]), SNMP has the
   value 161:

   Keyword    Decimal    Description
   snmp       161/tcp    SNMP
   snmp       161/udp    SNMP

   So, in the case of the standardized IANA layer 4 SNMP port, the
   Classification Engine ID is 3, and the Selector ID has the value of
   161.

   Therefore, the Application ID is encoded as:

       0                   1
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |       3       |              161              |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Example 6: Layer 7 Application with Private Enterprise Number

   In this example, the layer 7 Webex traffic from Example 5 above have
   been classified by enterprise X.  The exported records have been
   received by enterprise Y's mediation device, which wishes to forward
   them to a top-level Collector.

   In order for the top-level Collector to know that the records were
   classified by enterprise X, the enterprise Y mediation device must
   report the records using the PANA-L7-PEN Classification Engine ID
   with enterprise X's Private Enterprise Number.

   The PANA-L7-PEN Classification Engine ID is 20, and enterprise X's
   Selector ID for Webex traffic has the value of 10000.  From Table 2

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   the Selector ID length is 3 for the PANA-L7-PEN Engine ID.

   Therefore, the Application ID is encoded as:

    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
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |      20       |               enterprise ID = X            ...|
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |...Ent.ID.contd|                     10000                     |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   The format '20..X..10000' is used for simplicity in the examples
   below.

   (postamble)

Authors' Addresses

   Reinaldo Penno
   Cisco Systems, Inc.
   170 West Tasman Dr
   San Jose  CA
   USA

   Email: repenno@cisco.com

   Benoit Claise
   Cisco Systems, Inc.
   De Kleetlaan 6a b1
   1831 Diegem
   Belgium

   Email: bclaise@cisco.com

   Carlos Pignataro
   Cisco Systems, Inc.
   7200-12 Kit Creek Road
   Research Triangle Park, NC  27709-4987
   USA

   Email: cpignata@cisco.com

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   Christophe Fontaine
   Qosmos
   8 rue Bernard Buffer
   Paris
   France

   Email: christophe.fontaine@qosmos.com

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