N. Venna Internet Draft Brix Networks Expires: September 2007 K. Hedayat Brix Networks R.Krzanowski Verizon G.Dion Alcatel-Lucent March 2007 RTCP XR - Report Block for IPTV Metrics draft-venna-avt-rtcpxr-iptv-01 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. Copyright Notice Copyright (C) The IETF Trust (2007). Venna, et al. Expires September 2007 [Page 1] Internet-Draft RTCP XR for IPTV Streams March, 2007 Abstract This document defines a new report block for the Extended Report (XR) packet type of the RTP Control Protocol (RTCP) for use by IPTV applications. The report block supports monitoring of IPTV streams by providing a mechanism for IPTV clients to report on the performance of different aspects of the IPTV stream. Table of Contents 1. Introduction..................................................2 2. Terminology...................................................3 3. Background....................................................3 4. IPTV Metrics Report Block.....................................3 4.1 Main Block Format.........................................4 4.2 Program sub-block Format..................................6 4.3 Elementary Stream sub-block Format........................8 5. Security Considerations.......................................9 6. IANA Considerations..........................................10 7. Normative References.........................................10 8. Informative References.......................................10 1. Introduction As the number of IPTV deployments continue to increase, it becomes necessary for the operator to collect various metrics on the streams that are being delivered to understand the quality of the service that a user is receiving. This draft defines a new report block for the Extended Report (XR) packet type of the RTP Control Protocol (RTCP) that allows IPTV clients to report to a server on various aspects of the stream that is being delivered to them. [RFC3611] defines the XR packet type for RTCP as well as how XR packets can be signaled by an application that uses Session Description Protocol (SDP). The document further defines seven report block formats to convey information beyond that already contained in the reception report blocks of RTCP's Sender Report (SR) or Receiver Report (RR) packets. The new block type defined in this draft is the IPTV Metrics block. The data reported by a client is intended to be useful in understanding the short-term performance of the IPTV service as well as long-term indicators for network configuration. Venna, et al. Expires September 2007 [Page 2] Internet-Draft RTCP XR for IPTV Streams March, 2007 2. Terminology 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 [RFC2119]. 3. Background [RFC2250] specifies the RTP payload format for MPEG1/MPEG2 Video. The specification describes how to encapsulate MPEG System and Transport streams within the RTP payload. For MPEG2 transport streams, the RTP payload will contain an integral number of MPEG2 transport packets. Futher, a small number of these transport packets (normally fixed in size at 188 bytes) are aggregated into a single RTP packet. The number of transport packets contained is computed by dividing the RTP payload length by the length of a transport packet. ISO/IEC 13818-1 addresses the combining of one or more elementary streams of video and audio, as well as other data, into single or multiple streams eligible for transmission. MPEG-2 Transport stream packets are made of packets from various elementary streams (audio, video, data) and Program Specific Information (PSI) tables. The four PSI tables viz. Program Association Table (PAT), Program Map Table (PMT), Conditional Access Table (CAT), and Network Information Table (NIT) contain the necessary and sufficient information to demultiplex and present programs. The audio and video elementary streams can carry data encoded using various codecs such as MPEG-1 Audio, MPEG-2 Video, H.264 etc. The new reporting blocks defined in this draft report metrics from various encapsulations and views of the media stream - RTP, MPEG-2 TS, Programs, Elementary Streams. An IPTV client SHOULD use report blocks specified in [RFC3611] and [RFC3550] to report some of the metrics that are relevant to understanding the performance of the media stream. For instance, the client SHOULD use RTCP Reception Report (RR) to report on the cumulative number of packets lost, interarrival jitter etc. The client SHOULD also use the Statistics Summary Report Block of the RTCP Extended Reports to report detailed metrics about lost and duplicate packets, min/max/avg/standard deviation of jitter for a range of sequence numbers. 4. IPTV Metrics Report Block Venna, et al. Expires September 2007 [Page 3] Internet-Draft RTCP XR for IPTV Streams March, 2007 This block reports metrics on a range of packets received for the IPTV stream by a client. 4.1 Main Block 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=X | reserved | block length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | SSRC of source | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | begin_seq | end_seq | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Duplicate Pkts | Out of Order Pkts | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Lost Pkts | Noticeable Lost Pkts | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Min Jitter | Max Jitter | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Avg Jitter | Std Dev of Jitter | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | # of Loss Periods | Min Loss Period size | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Max Loss Period size | Avg Loss Period size | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | # of First Priority Errors | # of Second Priority Errors | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Max PAT Gap | Avg PAT Gap | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | # of Programs |Loss Constaint | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ : Program Data (Program Sub block) ... : +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ block type (BT): 8 bits A IPTV Metrics Report Block is identified by the constant TBD. reserved: 8 bits This field is reserved for future definition. In the absence of such definition, the bits in this field MUST be set to zero and MUST be ignored by the receiver. block length: 16 bits As defined in Section 3 of [RFC3611]. SSRC of source: 32 bits Venna, et al. Expires September 2007 [Page 4] Internet-Draft RTCP XR for IPTV Streams March, 2007 As defined in Section 4.1 of [RFC3611]. begin_seq: 16 bits The first sequence number that this block reports on. end_seq: 16 bits The last sequence number that this block reports on plus one. duplicate packets: 16 bits The number of duplicate packets received in the above sequence number interval. out of order packets: 16 bits The number of out-of-order packets received in the above sequence number interval. lost packets: 16 bits The number of lost packets in the above sequence number interval. noticeable lost packets: 16 bits The number of noticeable lost packets as defined in RFC 3357. The loss constraint is specified later. min jitter: 16 bits The minimum jitter of received packets in the above sequence specified in milli seconds. max jitter: 16 bits The maximum jitter of received packets in the above sequence specified in milli seconds. avg jitter: 16 bits The average jitter of received packets in the above sequence specified in milli seconds. std deviation of jitter: 16 bits The standard deviation of jitter of received packets in the above sequence specified in milli seconds. # of loss periods: 16 bits The number of loss periods in the above sequence as defined in [RFC3357]. min loss period size: 16 bits The number of packets lost in the loss period of the smallest size. max loss period size: 16 bits The number of packets lost in the loss period of the largest size. Venna, et al. Expires September 2007 [Page 5] Internet-Draft RTCP XR for IPTV Streams March, 2007 avg loss period size: 16 bits The avg number of packets lost each of the loss periods. # of First Priority Errors: 16 bits The number of first priority errors in the MPEG-2 TS as specified in ETSI TR 101 290. This includes Sync loss errors, Sync byte errors, PAT errors, Continuity counter errors, PMT errors, and PID errors. # of Second Priority Errors: 16 bits The number of second priority errors in the MPEG-2 TS as specified in ETSI TR 101 290. This includes TS errors, CRC errors, PCR errors, PTS errors, and CAT errors. max PAT gap: 16 bits The maximum gap between two successive PAT pkts in milli seconds. This metric is related to channel change time. avg PAT gap: 16 bits The average gap between two successive PAT pkts in milli seconds. This metric is related to channel change time. # of programs: 16 bits The total number of programs carried in this transport stream. For each program, a separate block is reported. loss constraint: 8 bits The value of loss constraint used to compute noticeable lost packets. 4.2 Program sub-block 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | PID | Number | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Max PMT Gap | Avg PMT Gap | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Max PCR Gap | Avg PCR Gap | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Min PCR Jitter | Max PCR Jitter | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Avg PCR Jitter | Std Dev of PCR Jitter | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Start Time | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Stop Time | Venna, et al. Expires September 2007 [Page 6] Internet-Draft RTCP XR for IPTV Streams March, 2007 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | # of Program Pkts | # of ES | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ : ES Data (ES Sub block) ... : +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ PID: 16 bits The Packet ID of the PMT for this program. Number: 16 bits The program number. max PAT gap: 16 bits The maximum gap between two successive PMT pkts in milliseconds. This metric is related to channel change time. avg PAT gap: 16 bits The average gap between two successive PMT pkts in milliseconds. This metric is related to channel change time. max PCR gap: 16 bits The maximum gap between two successive pkts that have a PCR in them. avg PCR gap: 16 bits The average gap between two successive pkts that have a PCR in them. min PCR jitter: 16 bits The minimum jitter of PCR clock in the above sequence specified in milliseconds. max PCR jitter: 16 bits The maximum jitter of PCR clock in the above sequence specified in milliseconds. avg PCR jitter: 16 bits The average jitter of PCR clock in the above sequence specified in milliseconds. std deviation of PCR jitter: 16 bits The standard deviation of the jitter of PCR clock in the above sequence specified in milliseconds. Start time: 32 bits The middle 32 bits of the 64 bits of the NTP timestamp when the presence of this program was first detected. Stop time: 32 bits The middle 32 bits of the 64 bits of the NTP timestamp when the presence of this program was terminated. If the program is Venna, et al. Expires September 2007 [Page 7] Internet-Draft RTCP XR for IPTV Streams March, 2007 still running, it should be set to 0. # of program packets: 16 bits The number of packets in the above sequence that belong to this program. # of ES: 16 bits The total number of ES that belong to this program. For each ES, a separate block is reported. 4.3 Elementary Stream sub-block 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | PID | Number of PES Pkts | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Number of Frames | Complete Frames Lost | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Duplicate Pkts | Out of Order Pkts | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Lost Pkts | Partial Frames Rcvd | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | # of Loss Periods | Min Loss Period size | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Max Loss Period size | Avg Loss Period size | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Noticeable lost |Loss Constaint | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Start Time | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Stop Time | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ PID: 16 bits The Packet ID of the ES. Number of PES Pkts: 16 bits The number of TS pkts that belong to this ES. Number of Frames: 16 bits The number of frames received for this ES. Complete Frames Lost: 16 bits The number of complete frames lost for this ES. duplicate packets: 16 bits The number of duplicate packets received in the above sequence number interval. Venna, et al. Expires September 2007 [Page 8] Internet-Draft RTCP XR for IPTV Streams March, 2007 out of order packets: 16 bits The number of out-of-order packets received in the above sequence number interval. lost packets: 16 bits The number of lost packets in the above sequence number interval. Partial Frames Rcvd: 16 bits The number of partial frames rcvd for this ES. # of loss periods: 16 bits The number of loss periods in the above sequence as defined in [RFC3357]. min loss period size: 16 bits The number of packets lost in the loss period of the smallest size. max loss period size: 16 bits The number of packets lost in the loss period of the largest size. avg loss period size: 16 bits The avg number of packets lost each of the loss periods. noticeable lost packets: 16 bits The number of noticeable lost packets as defined in [RFC3357]. The loss constraint is specified later. loss constraint: 8 bits The value of loss constraint used to compute noticeable lost packets. Start time: 32 bits The middle 32 bits of the 64 bits of the NTP timestamp when the presence of this program was first detected. Stop time: 32 bits The middle 32 bits of the 64 bits of the NTP timestamp when the presence of this program was terminated. If the program is still running, it should be set to 0. 5. Security Considerations The security considerations of [RFC3611] apply. Venna, et al. Expires September 2007 [Page 9] Internet-Draft RTCP XR for IPTV Streams March, 2007 6. IANA Considerations A new block type for IPTV Metrics block should be registered with IANA. 7. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [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] Almeroth, K., Caceres, R., Clark, A., Cole, R., Duffield, N., Friedman, T., Hedayat, K., Sarac, K. and M. Westerlund, "RTP Control Protocol Extended Reports (RTCP XR)", RFC 3611, November 2003. 8. Informative References [RFC2250] Hoffman, D., Fernand, G., Goyal, V., Civanlar, M., "RTP Payload Format for MPEG1/MPEG2 Video", RFC 2250, January 1998. [RFC3357] Koodli, R., Ravikanth, R., "One-way Loss Pattern Sample Metrics", RFC 3357, August 2002. Authors' Addresses Nagarjuna Venna Brix Networks 285 Mill Road Chelmsford, MA 01824 US Phone: +1 978 367 5703 EMail: nvenna@brixnet.com URI: http://www.brixnet.com/ Venna, et al. Expires September 2007 [Page 10] Internet-Draft RTCP XR for IPTV Streams March, 2007 Kaynam Hedayat Brix Networks 285 Mill Road Chelmsford, MA 01824 US Phone: +1 978 367 5611 EMail: khedayat@brixnet.com URI: http://www.brixnet.com/ Roman M. Krzanowski, Ph.D. Verizon Technology Organization 500 Westchester Ave. White Plains, NY 10604 US Phone: +1 914 644 2395 EMail: roman.krzanowski@verizon.com URI: http://www.verizon.com/ Gino Dion Alcatel-Lucent 600 March Road Ottawa, Ontario, Canada K2K 2E6 Phone: +1 613 784 8745 EMail: gino.dion@alcatel-lucent.com URI: http://www.alcatel-lucent.com/ IPR Disclosure Acknowledgement The IETF takes no position regarding the validity or scope of any Intellectual Property Rights or other rights that might be claimed to pertain to the implementation or use of the technology described in this document or the extent to which any license under such rights might or might not be available; nor does it represent that it has made any independent effort to identify any such rights. 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 Venna, et al. Expires September 2007 [Page 11] Internet-Draft RTCP XR for IPTV Streams March, 2007 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. Disclaimer of Validity This document and the information contained herein are provided on an "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY, THE IETF TRUST AND THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Copyright Notice 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. Acknowledgment Funding for the RFC Editor function is currently provided by the Internet Society. Venna, et al. Expires September 2007 [Page 12]