[Docs] [txt|pdf|xml|html] [Tracker] [WG] [Email] [Diff1] [Diff2] [Nits]

Versions: (draft-huang-xrblock-rtcp-xr-decodability) 00 01 02 03 04 05 06 07 08 09 10 11 12 RFC 6990

Network Working Group                                           R. Huang
Internet-Draft                                                     Q. Wu
Intended status: Standards Track                                  Huawei
Expires: December 2, 2013                                      H. Asaeda
                                                                    NICT
                                                                 G. Zorn
                                                             Network Zen
                                                            May 31, 2013


    RTP Control Protocol (RTCP) Extended Report (XR) Block for MPEG2
  Transport Stream (TS) Program Specific Information (PSI) Independent
               Decodability Statistics Metrics reporting
               draft-ietf-xrblock-rtcp-xr-decodability-12

Abstract

   An MPEG2 Transport Stream (TS) is a standard container format used in
   the transmission and storage of multimedia data.  Unicast/Multicast
   MPEG2 TS over RTP is widely deployed in IPTV systems.  This document
   defines an RTP Control Protocol (RTCP) Extended Report (XR) Block
   that allows the reporting of MPEG2 TS decodability statistics metrics
   related to transmissions of MPEG2 TS over RTP.  The metrics specified
   in the RTCP XR Block are not dependent on Program specific
   information carried in MPEG TS.

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 December 2, 2013.

Copyright Notice

   Copyright (c) 2013 IETF Trust and the persons identified as the
   document authors.  All rights reserved.




Huang, et al.           Expires December 2, 2013                [Page 1]

Internet-Draft           RTCP XR TS Decodability                May 2013


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


Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3
     1.1.  MPEG2 Transport Stream Decodability Metrics  . . . . . . .  3
     1.2.  RTCP and RTCP XR Reports . . . . . . . . . . . . . . . . .  3
     1.3.  Performance Metrics Framework  . . . . . . . . . . . . . .  3
     1.4.  Applicability  . . . . . . . . . . . . . . . . . . . . . .  3
   2.  Terminology  . . . . . . . . . . . . . . . . . . . . . . . . .  4
     2.1.  Standards Language . . . . . . . . . . . . . . . . . . . .  4
   3.  MPEG2 TS PSI Independent Decodability Statistics Metrics
       Block  . . . . . . . . . . . . . . . . . . . . . . . . . . . .  4
   4.  SDP Signaling  . . . . . . . . . . . . . . . . . . . . . . . .  7
     4.1.  SDP rtcp-xr-attrib Attribute Extension . . . . . . . . . .  8
     4.2.  Offer/Answer Usage . . . . . . . . . . . . . . . . . . . .  8
   5.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . .  8
     5.1.  New RTCP XR Block Type value . . . . . . . . . . . . . . .  8
     5.2.  New RTCP XR SDP Parameter  . . . . . . . . . . . . . . . .  8
     5.3.  Contact information for registrations  . . . . . . . . . .  8
   6.  Security Considerations  . . . . . . . . . . . . . . . . . . .  9
   7.  Acknowledgements . . . . . . . . . . . . . . . . . . . . . . .  9
   8.  References . . . . . . . . . . . . . . . . . . . . . . . . . .  9
     8.1.  Normative References . . . . . . . . . . . . . . . . . . .  9
     8.2.  Informative References . . . . . . . . . . . . . . . . . . 10
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 10
















Huang, et al.           Expires December 2, 2013                [Page 2]

Internet-Draft           RTCP XR TS Decodability                May 2013


1.  Introduction

1.1.  MPEG2 Transport Stream Decodability Metrics

   The European Telecommunications Standards Institute (ETSI) has
   defined a set of syntax and information consistency tests and
   corresponding indicators [ETSI] that are recommended for the
   monitoring of MPEG2 Transport Streams [ISO-IEC.13818-1.2007].  The
   tests and corresponding indicators are grouped according to priority:

   o  First priority - Necessary for decodability (basic monitoring)
   o  Second priority - Recommended for continuous or periodic
      monitoring
   o  Third priority - Recommended for application-dependent monitoring

   This memo is based on information consistency tests and resulting
   indicators defined by ETSI [ETSI] and defines a new block type to
   augment those defined in [RFC3611] for use with MPEG2 Transport
   Stream (TS) [ISO-IEC.13818-1.2007].  The new block type supports
   reporting of the number of occurrences of each Program Specific
   Information (PSI) Independent indicator in the first and second
   priorities; third priority indicators are not supported.

1.2.  RTCP and RTCP XR Reports

   The use of RTCP for reporting is defined in [RFC3550].  [RFC3611]
   defined an extensible structure for reporting using an RTCP Extended
   Report (XR).  This document defines a new Extended Report block for
   use with [RFC3550] and [RFC3611].

1.3.  Performance Metrics Framework

   The Performance Metrics Framework [RFC6390] provides guidance on the
   definition and specification of performance metrics.  The RTP
   Monitoring Architectures [RFC6792] provides guideline for reporting
   block format using RTCP XR.  The new report block described in this
   memo is in compliance with the monitoring architecture specified in
   [RFC6792] and the Performance Metrics Framework [RFC6390].

1.4.  Applicability

   This block type allows a counts of MPEG Transport Stream quality
   metrics that are measured in accordance with ETSI TR 101290 [ETSI] to
   be reported by an endpoint.  These metrics are useful for identifying
   bitstream packetization and transport stream encoding problems that
   may affect the user's perception of a video service delivered over
   RTP.




Huang, et al.           Expires December 2, 2013                [Page 3]

Internet-Draft           RTCP XR TS Decodability                May 2013


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].


3.  MPEG2 TS PSI Independent Decodability Statistics Metrics Block

   ETSI TR 101290 [ETSI] generally defines metrics related to error
   events while this document contains counts of those metrics defined
   in [ETSI].  The block defined in this document reports MPEG2 TS PSI
   Independent decodability statistics metrics beyond the information
   carried in the standard RTCP packet format, which are measured at the
   receiving end of the RTP stream.  It contains counts of eight metrics
   defined in ETSI TR 101290 [ETSI].  Information is reported about
   basic monitoring parameters necessary to ensure that the TS can be
   decoded including:

   o  Transport Stream Synchronization Losses
   o  Sync byte errors
   o  Continuity count errors

   and continuous monitoring parameters necessary to ensure the
   continuous decoding including:

   o  Transport errors
   o  Program Clock Reference (PCR) errors
   o  PCR repetition errors
   o  PCR discontinuity indicator errors
   o  PCR accuracy errors
   o  Presentation Time Stamp (PTS) errors

   The other parameters are ignored since they do not apply to all MPEG2
   implementations.  For further information on these parameters, see
   [ETSI].  Note that when the report of this block spans across more
   than one measurement intervals [RFC6776], the count of the metrics
   (e.g., Sync byte errors, PCR errors )defined in [ETSI] may reflect a
   problem in the current or previous measurement interval.

   The MPEG2 TS PSI Independent Decodability Metrics Block has the
   following format:







Huang, et al.           Expires December 2, 2013                [Page 4]

Internet-Draft           RTCP XR TS Decodability                May 2013


       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=MTPID   |    Reserved   |         block length          |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                     SSRC of source                            |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |          begin_seq            |             end_seq           |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                      TS_sync_loss_count                       |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                      Sync_byte_error_count                    |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                  Continuity_count_error_count                 |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                      Transport_error_count                    |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                        PCR_error_count                        |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                   PCR_repetition_error_count                  |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |            PCR_discontinuity_indicator_error_count            |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                     PCR_accuracy_error_count                  |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                       PTS_error_count                         |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   block type (BT): 8 bits

      The MPEG2 TS PSI Independent Decodability Metrics Block is
      identified by the constant <MTPID>.

   Reserved: 8 bits

      These bits are reserved.  They MUST be set to zero by senders and
      ignored by receivers (See [RFC6709] section 4.2).

   block length: 16 bits

      The constant 11, in accordance with the definition of this field
      in Section 3 of RFC 3611.  The block MUST be discarded if the
      block length is set to a different value.








Huang, et al.           Expires December 2, 2013                [Page 5]

Internet-Draft           RTCP XR TS Decodability                May 2013


   SSRC of source: 32 bits

      As defined in Section 4.1 of RFC 3611.

   begin_seq: 16 bits

      The RTP sequence number corresponding to the start of the
      measurement period, as defined in Section 4.1 of RFC 3611.

   end_seq: 16 bits

      The RTP sequence number corresponding to the end of the
      measurement period, as defined in Section 4.1 of RFC 3611.

   TS_sync_loss_count: 32 bits

      A count of the number of TS_sync_loss errors that occurred in the
      above sequence number interval.  A TS_sync_loss error occurs when
      there are two or more consecutive incorrect sync bytes within the
      MPEG TS stream, as defined in section 5.2.1 of [ETSI].

   Sync_byte_error_count: 32 bits

      A count of the number of Sync_byte_errors that occurred in the
      above sequence number interval.  A sync byte error occurs when the
      sync byte is not equal to 0x47 in any TS packet contained in the
      MPEG TS stream, as defined in section 5.2.1 of [ETSI].

   Continuity_count_error_count: 32 bits

      A count of the number of Continuity_count_errors that occurred in
      the above sequence number interval.  A Continuity_count_error
      occurs when any of the following faults happen within the MPEG TS
      stream - incorrect packet order, a packet occurs more than twice
      or a packet is lost,as defined in the section 5.2.1 of [ETSI].

   Transport_error_count: 32 bits

      A count of the number of Transport_errors that occurred in the
      above sequence number interval.  A Transport_error occurs when
      erroneous TS packet can not be corrected within the MPEG TS
      stream. as defined in the section 5.2.2 of [ETSI].

   PCR_error_count: 32 bits

      A count of the number of PCR_errors that occurred in the above
      sequence number interval.  A PCR_error occurs if the primary clock
      reference (PCR) is not seen for more than 100ms within the MPEG TS



Huang, et al.           Expires December 2, 2013                [Page 6]

Internet-Draft           RTCP XR TS Decodability                May 2013


      stream, as defined in the section 5.2.2 of [ETSI].  The time
      interval between two consecutive PCR values should be no more than
      40ms.

   PCR_repetition_error_count: 32 bits

      A count of the number of PCR_repetition_errors that occurred in
      the above sequence number interval.  A PCR_repeition_error occurs
      when the time interval between two consecutive PCR values is more
      than 40ms within the MPEG TS stream,as defined in the section
      5.2.2 of [ETSI].

   PCR_discontinuity_indicator_error_count: 32 bits

      A count of the number of PCR_discontinuity_indicator_errors that
      occurred in the above sequence number interval.  A
      PCR_discontinuity_indicator_error occurs if the time interval
      between two consecutive PCR values is more than 100ms within the
      MPEG TS stream, as defined in the section 5.2.2 of [ETSI].

   PCR_accuracy_error_count: 32 bits

      A count of the Number of PCR_accuracy_errors that occurred in the
      above sequence number interval.  A PCR_accuracy_error occurs when
      the PCR accuracy of the selected program is outside the range of
      +/-500ns within the MPEG TS stream,as defined in the section 5.2.2
      of [ETSI].

   PTS_error_count: 32 bits

      A count of the number of PTS_errors that occurred in the above
      sequence number interval.  A PTS_error occurs when the PTS
      repetition is more than 700ms within the MPEG TS stream, as
      defined in the section 5.2.2 of[ETSI].  Note that the PTS is
      contained in the MPEG-2 TS stream and is used to aid the decoder
      in presenting the program on time, at the correct speed and
      synchronized.



4.  SDP Signaling

   RFC 3611 defines the use of SDP (Session Description Protocol)
   [RFC4566] for signaling the use of RTCP XR blocks.  However XR blocks
   MAY be used without prior signaling (See section 5 of RFC3611).






Huang, et al.           Expires December 2, 2013                [Page 7]

Internet-Draft           RTCP XR TS Decodability                May 2013


4.1.  SDP rtcp-xr-attrib Attribute Extension

   This session augments the SDP attribute "rtcp-xr" defined in Section
   5.1 of RFC 3611 by providing an additional value of "xr-format" to
   signal the use of the report block defined in this document.

   xr-format =/  xr-tpid-block

   xr-tpid-block = "ts-psi-indep-decodability"

4.2.  Offer/Answer Usage

   When SDP is used in offer-answer context, the SDP Offer/Answer usage
   defined in [RFC3611] for unilateral "rtcp-xr" attribute parameters
   applies.  For detailed usage of Offer/Answer for unilateral
   parameter, refer to section 5.2 of [RFC3611].


5.  IANA Considerations

   New report block types for RTCP XR are subject to IANA registration.
   For general guidelines on IANA allocations for RTCP XR, refer to
   Section 6.2 of RFC 3611.

5.1.  New RTCP XR Block Type value

   This document assigns the block type value MTPID in the IANA " RTP
   Control Protocol Extended Reports (RTCP XR) Block Type Registry " to
   the "MPEG2 Transport Stream PSI Independent Decodability Statistics
   Metrics Block".

   [Note to RFC Editor: please replace MPITD with the IANA provided RTCP
   XR block type for this block.]

5.2.  New RTCP XR SDP Parameter

   This document also registers a new parameter "ts-psi-indep-
   decodability" in the "RTP Control Protocol Extended Reports (RTCP XR)
   Session Description Protocol (SDP) Parameters Registry".

5.3.  Contact information for registrations

   The contact information for the registrations is:

                    Qin Wu
                    sunseawq@huawei.com
                    101 Software Avenue, Yuhua District
                    Nanjing, JiangSu 210012 China



Huang, et al.           Expires December 2, 2013                [Page 8]

Internet-Draft           RTCP XR TS Decodability                May 2013


6.  Security Considerations

   There might be some relationship between reported error counters and
   contractual Service Level Agreements (SLA)s and hence an attack
   (e.g., RTP endpoints report fake information, or an attacker in the
   path modifies the data being reported ) may deliberately corrupt
   these error counters fields and will result in financial implications
   for the network operator (either as a result of un-needed Performance
   metrics, or penalty charges for SLA failure).

   A solution to prevent such attack is to apply an authentication and
   integrity protection framework for the RTCP XR report block.  This
   can be accomplished using the RTP profile that combines Secure RTP
   [RFC3711] and AVPF into SAVPF [RFC5124].

   Besides this, the proposed RTCP XR report block in this document
   introduces no other new security considerations beyond those
   described in [RFC3611].


7.  Acknowledgements

   Thanks to Ray van Brandenburg, Claire Bi, Colin Perkin, Roni Even,
   Dan Romascanu, Ali Begen and Alan Clark for useful review and
   suggestions.


8.  References

8.1.  Normative References

   [ETSI]     ETSI, "Digital Video Broadcasting (DVB); Measurement
              guidelines for DVB systems", Technical Report TR 101 290,
              2001.

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

   [RFC3550]  Schulzrinne, H., "RTP: A Transport Protocol for Real-Time
              Applications", RFC 3550, July 2003.

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

   [RFC3711]  Baugher, M., McGrew, D., Naslund, M., Carrara, E., and K.
              Norrman, "The Secure Real-time Transport Protocol (SRTP)",
              RFC 3711, March 2004.



Huang, et al.           Expires December 2, 2013                [Page 9]

Internet-Draft           RTCP XR TS Decodability                May 2013


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

   [RFC5124]  Ott, J. and E. Carrara, "Extended Secure RTP Profile for
              Real-time Transport Control Protocol (RTCP)-Based Feedback
              (RTP/SAVPF)", RFC 5124, February 2008.

8.2.  Informative References

   [ISO-IEC.13818-1.2007]
              International Organization for Standardization,
              "Information technology - Generic coding of moving
              pictures and associated audio information: Systems",
              ISO International Standard 13818-1, October 2007.

   [RFC6390]  Clark, A. and B. Claise, "Guidelines for Considering New
              Performance Metric Development", BCP 170, RFC 6390,
              October 2011.

   [RFC6709]  Carpenter, B., Aboba, B., and S. Cheshire, "Design
              Considerations for Protocol Extensions", RFC 6709,
              September 2012.

   [RFC6776]  Wu, Q., "Measurement Identity and information Reporting
              using SDES item and XR Block", RFC 6776, August 2012.

   [RFC6792]  Wu, Q., Hunt, G., and P. Arden, "Guidelines for Use of the
              RTP Monitoring Framework", RFC 6792, November 2012.


Authors' Addresses

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

   Email: rachel.huang@huawei.com












Huang, et al.           Expires December 2, 2013               [Page 10]

Internet-Draft           RTCP XR TS Decodability                May 2013


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

   Email: bill.wu@huawei.com


   Hitoshi Asaeda
   National Institute of Information and Communications Technology
   4-2-1 Nukui-Kitamachi
   Koganei, Tokyo  184-8795
   Japan

   Email: asaeda@nict.go.jp


   Glen Zorn
   Network Zen
   227/358 Thanon Sanphawut
   Bang Na, Bangkok  10260
   Thailand

   Phone: +66 (0) 909-201060
   Email: glenzorn@gmail.com

























Huang, et al.           Expires December 2, 2013               [Page 11]


Html markup produced by rfcmarkup 1.109, available from https://tools.ietf.org/tools/rfcmarkup/