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RTCP XR for Summary Statistics Metrics Reporting
draft-zorn-xrblock-rtcp-xr-al-stat-04

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This is an older version of an Internet-Draft whose latest revision state is "Replaced".
Authors Glen Zorn , Qin Wu , Rachel Huang , Roland Schott
Last updated 2012-01-18 (Latest revision 2011-10-13)
Replaced by draft-ietf-xrblock-rtcp-xr-summary-stat, RFC 7004
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draft-zorn-xrblock-rtcp-xr-al-stat-04
Network Working Group                                            G. Zorn
Internet-Draft                                               Network Zen
Intended status: Standards Track                               R. Schott
Expires: July 22, 2012                                  Deutsche Telekom
                                                                   Q. Wu
                                                                R. Huang
                                                                  Huawei
                                                        January 19, 2012

            RTCP XR for Summary Statistics Metrics Reporting
                 draft-zorn-xrblock-rtcp-xr-al-stat-04

Abstract

   This document defines three RTCP XR Report Blocks and associated SDP
   parameters that allows the reporting of loss, duplication and discard
   summary statistics metrics for use in a range of RTP applications.

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 July 22, 2012.

Copyright Notice

   Copyright (c) 2012 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
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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

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

   This document may contain material from IETF Documents or IETF
   Contributions published or made publicly available before November
   10, 2008.  The person(s) controlling the copyright in some of this
   material may not have granted the IETF Trust the right to allow
   modifications of such material outside the IETF Standards Process.
   Without obtaining an adequate license from the person(s) controlling
   the copyright in such materials, this document may not be modified
   outside the IETF Standards Process, and derivative works of it may
   not be created outside the IETF Standards Process, except to format
   it for publication as an RFC or to translate it into languages other
   than English.

Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  4
     1.1.  Applicability  . . . . . . . . . . . . . . . . . . . . . .  4
   2.  Terminology  . . . . . . . . . . . . . . . . . . . . . . . . .  4
     2.1.  Standards Language . . . . . . . . . . . . . . . . . . . .  4
   3.  Transport Layer Metrics  . . . . . . . . . . . . . . . . . . .  4
     3.1.  Burst/Gap Loss Summsary Statistics Block . . . . . . . . .  4
       3.1.1.  Report Block Structure . . . . . . . . . . . . . . . .  5
       3.1.2.  Definition of Fields in Loss Summary Statistics
               Block  . . . . . . . . . . . . . . . . . . . . . . . .  5
     3.2.  Burst/Gap Discard Summary Statistics Block . . . . . . . .  7
       3.2.1.  Report Block Structure . . . . . . . . . . . . . . . .  7
       3.2.2.  Definition of Fields in Discard Summary Statistics
               Block  . . . . . . . . . . . . . . . . . . . . . . . .  7
   4.  Application Layer Metrics  . . . . . . . . . . . . . . . . . .  8
     4.1.  Application Layer Loss/Duplication Statistics Summary
           Block  . . . . . . . . . . . . . . . . . . . . . . . . . .  9
       4.1.1.  Report Block Structure . . . . . . . . . . . . . . . .  9
       4.1.2.  Definition of Fields in Loss/Duplication Summary
               Statistics Block . . . . . . . . . . . . . . . . . . .  9
   5.  SDP Signaling  . . . . . . . . . . . . . . . . . . . . . . . . 11
   6.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 11
     6.1.  New RTCP XR Block Type values  . . . . . . . . . . . . . . 11
     6.2.  New RTCP XR SDP Parameters . . . . . . . . . . . . . . . . 12
     6.3.  Contact information for registrations  . . . . . . . . . . 12
   7.  Security Considerations  . . . . . . . . . . . . . . . . . . . 12
   8.  Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 12
   9.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 13
     9.1.  Normative References . . . . . . . . . . . . . . . . . . . 13
     9.2.  Informative References . . . . . . . . . . . . . . . . . . 13
   Appendix A.  Change Log  . . . . . . . . . . . . . . . . . . . . . 14

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   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 14

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1.  Introduction

   RFC 3611 [RFC3611] defines seven report block formats for network
   management and quality monitoring.  However, some of these metrics
   are mostly for multicast inference of network characteristics (MINC)
   or voice over IP (VoIP) monitoring and not widely applicable to other
   applications, e.g., video quality monitoring.  This document focuses
   on specifying new additional report block types used to convey loss,
   duplication and discard summary statistics that are generically
   designed for use in audio and video services.

   The metrics belong to both the class of application layer metrics and
   transport layer metrics defined in [MONARCH] (work in progress).

1.1.  Applicability

   The Report Blocks defined in this document can be applied to any
   real-time applications that convey loss, duplication and discard
   summary statistics.

2.  Terminology

2.1.  Standards 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].

   In addition, the following terms are defined:

   Picture Type

      Picture types used in the different video algorithms compose of
      the key-frame and the Derivation frame.  Key-frame is also called
      a reference frame and used as a reference for predicting other
      pictures.  It is coded without prediction from other pictures.
      The Derivation frame is derived from Key-frame using prediction
      from the reference frame.

3.  Transport Layer Metrics

3.1.  Burst/Gap Loss Summsary Statistics Block

   The metrics described here are intended to be used as described in
   this section, in conjunction with information from the Measurement

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   Information block (which MUST be present in the same RTCP packet as
   the Burst/Gap Loss block) and also with the metric "cumulative number
   of packets lost" provided in standard RTCP [RFC3550].

3.1.1.  Report Block Structure

       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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |     BT=TBD    |I|    rsv.     |        block length           |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                         SSRC of Source                        |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |        Burst Loss Rate        |         Gap Loss Rate         |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |       Burst duration Mean     |    Burst duration Varianc     |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

3.1.2.  Definition of Fields in Loss Summary Statistics Block

   block type (BT): 8 bits

      Burst/Gap Loss Summsary Statistics Block is identified by the
      constant <BGLSS>.

   Interval Metric flag (I): 1 bit

      This field is used to indicate whether the metrics block is an
      Interval or a Cumulative report,

   reserved: 7 bits

      This field is reserved for future definition.  In the absence of
      such a definition, the bits in this field MUST be set to zero and
      MUST be ignored by the receiver.

   block length: 16 bits

      The constant 2, in accordance with the definition of this field in
      Section 3 of RFC 3611 [RFC3611].

   SSRC of source: 32 bits

      As defined in Section 4.1 of RFC3611 [RFC3611].

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   Burst Loss Rate: 16 bits

      The fraction of packets lost during bursts since the beginning of
      reception, expressed as a fixed point number with the binary point
      at the left edge of the field.  This value is calculated by
      dividing Packets Discarded in Bursts by Total Packets expected in
      Bursts as follows:

      Packets Loss in Bursts / Total Packets expected in Bursts

   Gap Loss Rate: 16 bits

      The fraction of packets lost during gaps since the beginning of
      reception expressed as a fixed point number with the binary point
      at the left edge of the field.  This value is calculated by
      dividing the difference between number of packets lost and Packets
      lost in Bursts by the difference between Packets Expected and
      Total Packets expected in Bursts as follows:

      (number of packets lost - Packets Lost in Bursts) / (Packets
      Expected - Total Packets expected in Bursts)

      where "number of packets lost" is obtained from standard RTCP
      [RFC3550] and Packets Expected is calculated as the difference
      between "extended last sequence number" and "extended first
      sequence number" (Interval or Cumulative) provided in the
      Measurement Identity and Information block [MEASIDENT].

      Note that if the metric is to be calculated on an Interval basis,
      a difference must be taken between the current and preceding
      values of "cumulative number of packets lost" in RTCP, to obtain
      the "number of packets lost" for the reporting interval.

   Burst duration Mean:16bits

      The mean burst duration is obtained as the quotient:

      mean = Sum of Burst Durations / Number of Bursts

      where " Sum of Burst Durations " and "Number of Bursts"is obtained
      from the RTCP XR Burst/Gap Discard Block.

   Burst Duration Variance:16bits

      The variance of the burst duration is obtained using the standard
      result:

      var = ( Sum of Squares of Burst Durations - Number of Bursts *

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      mean^2 ) / (Number of Bursts - 1)

      where " Sum of Squares of Burst Durations " and "Number of
      Bursts"is obtained from the RTCP XR Burst/Gap Discard Block.

3.2.  Burst/Gap Discard Summary Statistics Block

   The metrics described here are intended to be used as described in
   this section, in conjunction with information from the Measurement
   Identity block (which MUST be present in the same RTCP packet as the
   Burst/Gap Discard block) and also with the metric "number of packets
   discarded" provided in the RTCP XR Discard Block [DISCARD].  The RTCP
   XR Discard Block SHOULD be sent if the Burst/Gap Discard block is
   sent, but the converse does not apply.

3.2.1.  Report Block Structure

      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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |     BT=TBD    |I|     Rsv.    |        block length           |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                          SSRC of Source                       |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |          Burst Discard Rate   |        Gap Discard Rate       |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

3.2.2.  Definition of Fields in Discard Summary Statistics Block

   block type (BT): 8 bits

      Burst/Gap Discard Summary Statistics Block is identified by the
      constant <BGDSS>.

   reserved: 8 bits

      This field is reserved for future definition.  In the absence of
      such a definition, the bits in this field MUST be set to zero and
      MUST be ignored by the receiver.

   Interval Metric flag (I): 1 bit

      This field is used to indicate whether the metrics block is an
      Interval or a Cumulative report,

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   reserved: 7 bits

      This field is reserved for future definition.  In the absence of
      such a definition, the bits in this field MUST be set to zero and
      MUST be ignored by the receiver.

   block length: 16 bits

      The constant 3, in accordance with the definition of this field in
      Section 3 of RFC 3611 [RFC3611].

   SSRC of source: 32 bits

      As defined in Section 4.1 of RFC3611 [RFC3611].

   Burst Discard Rate: 16 bits

      The fraction of packets discarded during bursts since the
      beginning of reception, expressed as a fixed point number with the
      binary point at the left edge of the field.  This value is
      calculated by dividing Packets Discarded in Bursts by Total
      Packets expected in Bursts as follows:

      Packets Discarded in Bursts / Total Packets expected in Bursts

   Gap Discard Rate: 16 bits

      The fraction of packets discarded during gaps since the beginning
      of reception expressed as a fixed point number with the binary
      point at the left edge of the field.  This value is calculated by
      dividing the difference between number of packets discarded and
      Packets Discarded in Bursts by the difference between Packets
      Expected and Total Packets expected in Bursts as follows:

      (number of packets discarded - Packets Discarded in Bursts) /
      (Packets Expected - Total Packets expected in Bursts)

      where "number of packets discarded" is obtained from the RTCP XR
      Discard Block [DISCARD] and Packets Expected is calculated as the
      difference between "extended last sequence number" and "extended
      first sequence number" (Interval or Cumulative) provided in the
      Measurement Information block [MEASIDENT].

4.  Application Layer Metrics

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4.1.  Application Layer Loss/Duplication Statistics Summary Block

   This block reports statistics beyond the information carried in the
   Statistics Summary Report Block RTCP packet specified in the section
   4.6 of RFC 3611 [RFC3611].  Information is recorded about lost frames
   ,duplicated frames, lost partial frames.  Such information can be
   useful for network management and video quality monitoring.

4.1.1.  Report Block Structure

       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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |     BT=TBD    | |T|P|   rsv.  |        block length           |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                        SSRC of Source                         |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |          begin_seq            |             end_seq           |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                    Number of frames expected                  |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                      lost_full_frames                         |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                          dup_frames                           |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                      lost_partial_frames                      |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

4.1.2.  Definition of Fields in Loss/Duplication Summary Statistics
        Block

   Block type (BT): 8 bits

      Application Layer Loss/Duplication Statistics Summary Bloc is
      identified by the constant <ALDSS>.

   Picture type indicator (T): 1 bit

      Picture types used in the different video algorithms compose of
      key-frame and derivation frame.  This field is used to indicate
      the frame type to be reported.  Bits set to 0 if the lost_frames
      field or dup_frames field contain a key_frame report or reference
      frame report, 1 if the lost_frames field and dup_frames field
      contain other derivation frame report.

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   P: 1 bit

      Bit set to 1 if the partial_lost_frames field or the partial_dup_
      frames field contains a report, 0 otherwise.

   Rsv.: 6 bits

      This field is reserved for future definition.  In the absence of
      such a definition, the bits in this field MUST be set to zero and
      MUST be ignored by the receiver.

   Block length: 16 bits

      The constant 6, in accordance with the definition of this field in
      Section 3 of RFC 3611 [RFC3611].

   SSRC of source: 32 bits

      As defined in Section 4.1 of RFC3611 [RFC3611].

   begin_seq: 16 bits

      As defined in Section 4.1 of RFC 3611 [RFC3611].

   end_seq: 16 bits

      As defined in Section 4.1 of RFC 3611 [RFC3611].

   number of frames expected:32bits

      A count of the number of frames expected, estimated if necessary.
      If no frames have been received then this count shall be set to
      Zero.

   lost_full_frames: 32 bits

      If one frame is completely lost, this frame is regarded as one
      lost full_frame.  The lost_full_frames is equivalent to the number
      of lost_full_frames in the above sequence number interval.

   dup_frames: 32 bits

      Number of dup_frames in the above sequence number interval.

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   lost_partial_frames: 32 bits

      If one frame is partially lost, this frame is regarded as one lost
      fractional frame.  The lost_partial_frames is equivalent to the
      number of lost_partial_frames in the above sequence number
      interval.

5.  SDP Signaling

   [RFC3611] defines the use of SDP (Session Description Protocol)
   [RFC4566] for signaling the use of XR blocks.  XR blocks MAY be used
   without prior signaling.

   This section augments the SDP [RFC4566] attribute "rtcp-xr" defined
   in [RFC3611] by providing three additional value of "xr-format" to
   signal the use of the report block defined in this document.

        rtcp-xr-attrib =  "a=rtcp-xr:"
                          [xr-format *(SP xr-format)] CRLF
              xr-format =
                          / burst-gap-loss-stat
                          / burst-gap-discard-stat
                          / application-loss-dup-stat

   Refer to Section 5.1 of RFC 3611 [RFC3611] for a detailed description
   and the full syntax of the "rtcp-xr" attribute.

6.  IANA Considerations

   New block types for RTCP XR are subject to IANA registration.  For
   general guidelines on IANA considerations for RTCP XR, refer
   to[RFC3611] .

6.1.  New RTCP XR Block Type values

   This document assigns three new block type value in the RTCP XR Block
   Type Registry:

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       Name:       BGLSS
       Long Name:  Burst/Gap Loss Summsary Statistics Block
       Value       <BGLSS>
       Reference:  Section 5.1

       Name:       BGDSS
       Long Name:  Burst/Gap Discard Summary Statistics Block
       Value       <BGDSS>
       Reference:  Section 5.2

       Name:       ALDSS
       Long Name:  Application Layer Loss/Duplication Statistics Summary
       Value       <ALDSS>
       Reference:  Section 6.1

6.2.  New RTCP XR SDP Parameters

   This document also registers three new SDP [RFC4566] parameters for
   the "rtcp-xr" attribute in the RTCP XR SDP Parameters Registry:

    *  " burst-gap-loss-stat "
    *  " burst-gap-discard-stat "
    *  "application-loss-dup-stat "

6.3.  Contact information for registrations

   The contact information for the registrations is:

       Glen Zorn
       Network Zen
       227/358 Thanon Sanphawut
       Bang Na, Bangkok  10110
       Thailand

7.  Security Considerations

   The new RTCP XR report blocks proposed in this document introduces no
   new security considerations beyond those described in [RFC3611].

8.  Acknowledgements

   The authors would like to thank Bill Ver Steeg, David R Oran, Ali
   Begen,Colin Perkins, Roni Even,Youqing Yang, Wenxiao Yu and Yinliang
   Hu for their valuable comments and suggestions on this document.

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9.  References

9.1.  Normative References

   [DISCARD]  Hunt, G., "RTCP XR Report Block for Discard metric
              Reporting", ID draft-ietf-rtcp-xr-discard-02, May 2009.

   [I-D.ietf-avt-rtp-svc]
              Wenger, S., Wang, Y., Schierl, T., and A. Eleftheriadis,
              "RTP Payload Format for Scalable Video Coding",
              draft-ietf-avt-rtp-svc-27 (work in progress),
              February 2011.

   [MEASIDENT]
              Wu, Q., "Measurement Identity and information Reporting
              using SDES item and XR Block",
              ID draft-ietf-xrblock-rtcp-xr-meas-identity-01,
              October 2011.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC2250]  Hoffman, D., Fernando, G., Goyal, V., and M. Civanlar,
              "RTP Payload Format for MPEG1/MPEG2 Video", RFC 2250,
              January 1998.

   [RFC3357]  Koodli, R. and R. Ravikanth, "One-way Loss Pattern Sample
              Metrics", RFC 3357, August 2002.

   [RFC3550]  Schulzrinne, H., Casner, S., Frederick, R., and V.
              Jacobson, "RTP: A Transport Protocol for Real-Time
              Applications", STD 64, RFC 3550, July 2003.

   [RFC3611]  Friedman, T., Caceres, R., and A. Clark, "RTP Control
              Protocol Extended Reports (RTCP XR)", RFC 3611,
              November 2003.

   [RFC4566]  Handley, M., Jacobson, V., and C. Perkins, "SDP: Session
              Description Protocol", RFC 4566, July 2006.

   [RFC5234]  Crocker, D. and P. Overell, "Augmented BNF for Syntax
              Specifications: ABNF", STD 68, RFC 5234, January 2008.

9.2.  Informative References

   [DSLF]     Rahrer, T., Ed., Fiandra, Ed., and Wright, Ed., "Triple-
              play Services Quality of Experience (QoE) Requirements",
              DSL Forum Technical Report TR-126, December 2006.

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   [MONARCH]  Wu, Q., "Monitoring Architectures for RTP",
              ID draft-ietf-avtcore-monarch-00, April 2011.

   [PMOL]     Clark, A., "Framework for Performance Metric Development",
              ID draft-ietf-pmol-metrics-framework-08, January 2011.

Appendix A.  Change Log

   This document is separated from
   draft-wu-xrblock-rtcp-xr-quality-monitoring-01 with a few editorial
   changes and focuses on loss,duplication, discard, and summary
   statistics metrics.

Authors' Addresses

   Glen Zorn
   Network Zen
   77/440 Soi Phoomjit, Rama IV Road
   Phra Khanong, Khlong Toie
   Bangkok  10110
   Thailand

   Phone: +66 (0) 87 502 4274
   Email: gwz@net-zen.net

   Roland Schott
   Deutsche Telekom
   Deutsche-Telekom-Allee 7
   Darmstadt  64295
   Germany

   Email: Roland.Schott@telekom.de

   Qin Wu
   Huawei
   101 Software Avenue, Yuhua District
   Nanjing, Jiangsu  210012
   China

   Email: sunseawq@huawei.com

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   Rachel Huang
   Huawei
   101 Software Avenue, Yuhua District
   Nanjing  210012
   China

   Email: Rachel@huawei.com

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