Network Working Group R. Huang Internet-Draft Q. Wu Intended status: Standards Track Huawei Expires: April 19, 2011 October 16, 2010 RTCP XR Report Block for TS Decodability Statistics Metric reporting draft-huang-avt-rtcp-xr-decodability-00 Abstract This document defines an RTCP XR Report Block that allows the reporting of Decodability Statistics Metric used for Transport Stream. 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 April 19, 2011. Copyright Notice Copyright (c) 2010 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 the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Huang & Wu Expires April 19, 2011 [Page 1] Internet-Draft RTCP XR Decodability Report Blocks October 2010 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2.1. Standards Language . . . . . . . . . . . . . . . . . . . . 3 2.2. Acronyms . . . . . . . . . . . . . . . . . . . . . . . . . 3 3. TR 101 290 Decodability Statistics Metric Report Block . . . . 3 4. SDP Signaling . . . . . . . . . . . . . . . . . . . . . . . . . 6 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 7 6. Security Considerations . . . . . . . . . . . . . . . . . . . . 8 7. References . . . . . . . . . . . . . . . . . . . . . . . . . . 8 7.1. Normative References . . . . . . . . . . . . . . . . . . . 8 7.2. Informative References . . . . . . . . . . . . . . . . . . 8 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 9 Huang & Wu Expires April 19, 2011 [Page 2] Internet-Draft RTCP XR Decodability Report Blocks October 2010 1. Introduction This draft defines a new block type to augment those defined in [RFC3611] for use in Transport Stream. The new block type supports the reporting of consistency of Transport Stream [ETSI]. This new block type can be useful for identifying the existence, and characterising the severity, of a packet transport problem which may affect users' perception of a service delivered over RTP, also useful for Verifying the continued correct operation of an existing system management and providing accurate measures of Transport Stream quality for operators. The metric is applicable to any other types of RTP application that use TS standard format for transmission and storage of audio, video, and data. 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: 2.2. Acronyms SSRC Synchronization Source [RFC3550] TS Transport Stream [ISO-IEC.13818-1.2007] 3. TR 101 290 Decodability Statistics Metric Report Block This block reports decodability statistics metric beyond the information carried in the standard RTCP packet format. Information is recorded about the number of Transport Stream Synchronization Losses, Sync byte errors, Continuity count errors, Transport errors, Program Clock Reference (PCR) errors, PCR repetition errors, PCR discontinuity indicator errors, and Presentation Time Stamp (PTS) errors [ETSI]. Such information can be useful for network management and video quality monitoring. Note that this is not only applicable to MPEG-2 RTP streams Huang & Wu Expires April 19, 2011 [Page 3] Internet-Draft RTCP XR Decodability Report Blocks October 2010 [RFC2250],but also applicable to any other video codec using Transport Stream as input. The report block contents are dependent upon a series of flag bits carried in the first part of the header. Not all parameters need to be reported in each block. Flags indicate which are and which are not reported. The fields corresponding to unreported parameters MUST be present, but are set to zero. The receiver MUST ignore any Decodability Metrics Block with a non-zero value in any field flagged as unreported. The Decodability Metrics Block has the following format: 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 |L|B|C|T|P|S|rvd| block length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | SSRC of source | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | begin_seq | end_seq | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Number of packets | Number of TSs | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Transport Stream Synchronization Losses | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Sync byte errors | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Continuity count errors | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Transport errors | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | PCR errors | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | PCR repetition errors | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | PCR discontinuity indicator errors | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | PTS errors | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ block type (BT): 8 bits A TR 101 290 decodability metrics report block is identified by the constant . Huang & Wu Expires April 19, 2011 [Page 4] Internet-Draft RTCP XR Decodability Report Blocks October 2010 Transport Stream Synchronization Loss flag (L): 1 bit Bit set to 1 if the Transport Stream Synchronization Loss field contains a report, 0 otherwise. Sync byte error flag (B): 1 bit Bit set to 1 if the Sync byte error field contains a report, 0 otherwise. Continuity count error flag (C): 1 bit Bit set to 1 if the Continuity count error field contains a report, 0 otherwise. Transport error flag (T): 1 bit Bit set to 1 if the Transport error field contains a report, 0 otherwise. PCR related error flag (P): 1 bit Bit set to 1 if the PCR error field, PCR repetition error field and PCR discontinuity indicator error fields contain a report, 0 otherwise. PTS error flag (S): 1 bit Bit set to 1 if the PTS error field contains a report, 0 otherwise. rvd: 2 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 10, 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]. begin_seq: 16 bits As defined in Section 4.1 of [RFC3611]. end_seq: 16 bits As defined in Section 4.1 of [RFC3611]. Number of Packets: 16 bits Number of RTP packets in the above sequence number interval. Huang & Wu Expires April 19, 2011 [Page 5] Internet-Draft RTCP XR Decodability Report Blocks October 2010 Number of TSs: 16 bits Number of Transport Streams in the above sequence number interval. Transport Stream Synchronization Losses: 32 bits Number of Transport Stream Synchronization Losses in the above sequence number interval. Sync byte errors: 32 bits Number of Transport sync byte errors in the above sequence number interval. Continuity count error: 32 bits Number of Transport Continuity count errors in the above sequence number interval. Transport errors: 32 bits Number of Transport errors in the above sequence number interval. PCR errors: 32 bits Number of PCR errors in the above sequence number interval. PCR repetition errors: 32 bits Number of Transport PCR repetition errors in the above sequence number interval. PCR discontinuity indicator errors: 32 bits Number of PCR discontinuity indicator errors in the above sequence number interval. PTS errors: 32 bits Number of PTS errors in the above sequence number interval. 4. SDP Signaling One new parameters are defined for the one report blocks defined in this document to be used with Session Description Protocol (SDP) [RFC4566] using the Augmented Backus-Naur Form (ABNF) [RFC5234]. They have the following syntax within the "rtcp-xr" attribute [RFC3611]: Huang & Wu Expires April 19, 2011 [Page 6] Internet-Draft RTCP XR Decodability Report Blocks October 2010 rtcp-xr-attrib = "a=rtcp-xr:" [xr-format *(SP xr-format)] CRLF xr-format = decodability-metrics decodability-metrics = "decodability-metrics" ["=" stat-flag *("," stat-flag)] stat-flag = "TS Synchronization Loss " / "Sync byte error " / "Continuity count error " / "Transport error" / "PCR related error" / "PTS error" Refer to Section 5.1 of RFC 3611 [RFC3611] for a detailed description and the full syntax of the "rtcp-xr" attribute. 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 [RFC3611]. This document assigns one new block type values in the RTCP XR Block Type Registry: Name: TDM Long Name: TR 101 290 Decodability Metrics Value Reference: section 3 This document also registers one SDP [RFC4566] parameters for the "rtcp-xr" attribute in the RTCP XR SDP Parameters Registry: * "decodability-metrics" The contact information for the registrations is: Rachel Huang Rachel@huawei.com 101 Software Avenue, Yuhua District Nanjing, JiangSu 210012 China Huang & Wu Expires April 19, 2011 [Page 7] Internet-Draft RTCP XR Decodability Report Blocks October 2010 6. Security Considerations TBC 7. References 7.1. Normative References [ETSI] ETSI, "Digital Video Broadcasting (DVB); Measurement guidelines for DVB systems", Technical Report TR 101 290, 2001. [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. [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. [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. 7.2. 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. [G.1082] ITU-T, "Measurement-based methods for improving the robustness of IPTV performance", ITU-T Huang & Wu Expires April 19, 2011 [Page 8] Internet-Draft RTCP XR Decodability Report Blocks October 2010 Recommendation G.1082, April 2009. [IEEE] IEEE, "Human Perception of Jitter and Media Synchronization", IEEE Journal on Selected Areas in Communications Vol. 14, No. 1, January 1996. [P.NAMS] ITU-T, "Non-intrusive parametric model for the Assessment of performance of Multimedia Streaming", ITU-T Recommendation P.NAMS, November 2009. Authors' Addresses Rachel Huang Huawei 101 Software Avenue, Yuhua District Nanjing 210012 China Email: Rachel@huawei.com Qin Wu Huawei 101 Software Avenue, Yuhua District Nanjing, Jiangsu 210012 China Email: sunseawq@huawei.com Huang & Wu Expires April 19, 2011 [Page 9]