Internet Engineering Task Force A. Clark Internet-Draft Telchemy Incorporated Expires: 4th January 2008 July 2007 RTCP XR - MPEG Transport Metrics Report Block draft-ietf-avt-rtcpxr-mpts-00 Status of this Memo By submitting this Internet-Draft, each author represents that any applicable patent or other IPR claims of which he or she is aware have been or will be disclosed, and any of which he or she becomes aware will be disclosed, in accordance with Section 6 of BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet-Drafts. 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." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt. The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. This Internet-Draft will expire on 4th January 2008. Copyright Notice Copyright (C) The IETF Trust (2007). Abstract This document defines an extension to the RTCP XR extended report packet type blocks to support the monitoring of video over IP and the associated audio streams, if present, for video encapsulated in MPEG Transport carried over RTP. [Note: this draft contains the MPEG transport metrics that were formerly in the draft-ietf-avt-rtcpxr-video-00.txt draft, which has now been divided into four drafts] Clark [Page 1] draft-ietf-avt-rtcpxr-mpts-00.txt July 2007 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Definitions . . . . . . . . . . . . . . . . . . . . . . . . 2 3. MPEG Transport Metrics Report Block . . . . . . . . . . . . 3 4. Summary . . . . . . . . . . . . . . . . . . . . . . . . . . 5 5. Security Considerations . . . . . . . . . . . . . . . . . . 5 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . 5 7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 5 8. Informative References . . . . . . . . . . . . . . . . . . . 5 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . Intellectual Property and Copyright Statements . . . . . . . 1. Introduction This draft defines a new block type to augment those defined in RFC3611 for use in Quality of Service reporting for video over IP. The new block type defined in this draft is the MPEG Transport Metrics Report Block. It is intended to support both the identification of problems affecting performance and the collection of data that may be useful in optimizing system configuration. The metrics defined in this document are based on terminology and error events described in ETSI TR 101 290 [5] that relate to MPEG Transport packets. The metrics that define summaries and counts of these error events are based on work within the ATIS IIF QoSM Working group [4] (Author's note, this is expected to be a published ATIS standard by Q3, 2007). 2. Definitions 2.1 MPEG-2 Transport Protocol The MPEG-2 Transport Protocol is a simple encapsulation of video or audio data into fixed length packets with a header. MPEG-2 Transport packets are often multiplexed and may be carried over RTP or directly over UDP. Clark [Page 2] draft-ietf-avt-rtcpxr-mpts-00.txt July 2007 3 Video Metrics Report Block 3.1 Block Description MPEG Transport Metrics 0 1 2 3 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | BT=N | | block length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | SSRC of source | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |0 0 0| Program ID | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Report Timestamp | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Measurement Interval (ms) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Continuity Error Count | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | TS Sync Loss Error Count | Sync Byte Error Count | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | PSI Error Count | PID Error Count | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | PCR Jitter | PCR Failure Count | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3.2.1 Header The header comprises: (i) Block Type for this report block (ii) Reserved (set to 0xFF) (iii) Block length in words (set to 0x0008) (iv) SSRC of the received RTP stream that this report refers to (v) Program ID (PID) for the audio or video stream to which this report relates (vi) Reserved (set to 0xFFFF) 3.2.2 Report Timestamp The time at which this report was generated (format?) 3.2.3 Measurement Interval The interval of time over which these metrics were measured, expressed in milliseconds. 3.2.4 Continuity Error Count A count of the number of Continuity_count_errors (as defined in TR 101 290 [5]). This count shall not be reset if the maximum value is reached. Clark [Page 3] draft-ietf-avt-rtcpxr-mpts-00.txt July 2007 Continuity count errors are defined as out-of-sequence, duplicate and lost packets. 3.2.5 TS Sync Loss Count A count of the number of TS_sync_loss errors (as defined in TR 101 290 [5]). This count shall not be reset if the maximum value is reached. TS sync loss errors are defined as a loss of sychronization by the transport stream. 3.2.6 Sync Byte Error Count A count of the number of Sync_byte_error errors (as defined in TR 101 290 [5]). This count shall not be reset if the maximum value is reached. Sync byte errors are defined as the value 0x47 not being present as the first byte of the MPEG transport header. 3.2.7 PSI Error Count A count of the number of PSI (Program Specific Information) errors. This count shall not be reset if the maximum value is reached. PSR errors are defined (in [4]) as TR 101 290 PAT and PMT errors including PAT_error, PAT_error_2, PMT_error, PMT_error_2, CRC error on PAT or PMT. 3.2.8 PID Error Count A count of the number of PID_errors (as defined in TR 101 290 [5]). This count shall not be reset if the maximum value is reached. A PID error is the condition that a packet with the specified PID has not occurred for a specified threshold period of time. 3.2.9 PCR Jitter The PCR Overall Jitter, as defined in TR 101 290 [5] expressed in microseconds. Video systems that do not rely on the accuracy of the PCR clock MAY set this value to 0. 3.2.10 PCR Failure Count A count of the number of PCR failures. This count shall not be reset if the maximum value is reached. PCR failures are defined as TR 101 290 PCR_error, PCR_repitition_ error, PCR_discontinuity_indicator_error, PCR_accuracy_error. Video systems that do not rely on the accuracy of the PCR clock MAY set this value to 0. Clark [Page 4] draft-ietf-avt-rtcpxr-mpts-00.txt July 2007 4. Summary This draft defines an RTCP XR report block for MPEG Transport, for use in video quality reporting. This is intended for in-service monitoring of video streaming, IPTV and IP videoconferencing services to provide real time performance feedback and support performance management. 5. IANA Considerations The block type "mmm" will need to be replaced with an IANA assigned number within those allocated for RTCP XR report blocks (RFC 3611). 6. Security Considerations RTCP reports can contain sensitive information since they can provide information about the nature and duration of a session established between two endpoints. As a result, any third party wishing to obtain this information should be properly authenticated and the information transferred securely. 7. Acknowledgments The metrics in this draft are based on work performed in the ATIS IIF QoSM WG. 8. Informative References [1] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [2] Schulzrinne, H., Casner, S., Frederick, R. and V. Jacobson, "RTP: A Transport Protocol for Real-Time Applications", STD 64, RFC 3550, July 2003. [3] Friedman, T., Caceres, R. and A. Clark, "RTP Control Protocol Extended Reports (RTCP XR)", RFC 3611, November 2003. [4] ATIS IIF [TBD], QoS Metrics for Linear Broadcast. [5] ETSI TR 101 290, Digital Video Broadcasting (DVB); Measurement guidelines for DVB Systems Authors' Addresses Alan Clark Telchemy Incorporated 2905 Premiere Parkway, Suite 280 Duluth, GA 30097 Email: alan@telchemy.com Clark [Page 5] draft-ietf-avt-rtcpxr-mpts-00.txt July 2007 Full Copyright Statement Copyright (C) The IETF Trust (2007). This document is subject to the rights, licenses and restrictions contained in BCP 78, and except as set forth therein, the authors retain all their rights. 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Information on the procedures with respect to rights in RFC documents can be found in BCP 78 and BCP 79. Copies of IPR disclosures made to the IETF Secretariat and any assurances of licenses to be made available, or the result of an attempt made to obtain a general license or permission for the use of such proprietary rights by implementers or users of this specification can be obtained from the IETF on-line IPR repository at http://www.ietf.org/ipr. The IETF invites any interested party to bring to its attention any copyrights, patents or patent applications, or other proprietary rights that may cover technology that may be required to implement this standard. Please address the information to the IETF at ietf- ipr@ietf.org. Acknowledgement Funding for the RFC Editor function is provided by the IETF Administrative Support Activity (IASA). Clark [Page 6]