Network Working Group J. Tong
Internet-Draft C. Bi, Ed.
Intended status: Standards Track China Telecom
Expires: December 7, 2014 R. Even
Gesher Erove Ltd
Q. Wu, Ed.
R. Huang
Huawei
June 5, 2014
RTP Control Protocol (RTCP) Extended Report (XR) Block for MPEG2
Transport Stream (TS) Program Specific Information (PSI) Decodability
Statistics Metrics reporting
draft-ietf-xrblock-rtcp-xr-psi-decodability-04
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 related to 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 7, 2014.
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Copyright Notice
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. MPEG2 Transport Stream Decodability Metrics . . . . . . . 2
1.2. RTCP and RTCP XR Reports . . . . . . . . . . . . . . . . 3
1.3. Performance Metrics Framework . . . . . . . . . . . . . . 3
1.4. Applicability . . . . . . . . . . . . . . . . . . . . . . 3
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.1. Standards Language . . . . . . . . . . . . . . . . . . . 4
3. MPEG2 TS PSI Decodability Statistics Metrics Block . . . . . 4
4. SDP Signaling . . . . . . . . . . . . . . . . . . . . . . . . 8
4.1. SDP rtcp-xr-attrib Attribute Extension . . . . . . . . . 8
4.2. Offer/Answer Usage . . . . . . . . . . . . . . . . . . . 8
4.3. Usage Outside of Offer/Answer . . . . . . . . . . . . . . 8
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8
5.1. New RTCP XR Block Type value . . . . . . . . . . . . . . 8
5.2. New RTCP XR SDP Parameter . . . . . . . . . . . . . . . . 9
5.3. Contact information for registrations . . . . . . . . . . 9
6. Security Considerations . . . . . . . . . . . . . . . . . . . 9
7. References . . . . . . . . . . . . . . . . . . . . . . . . . 9
7.1. Normative References . . . . . . . . . . . . . . . . . . 9
7.2. Informative References . . . . . . . . . . . . . . . . . 10
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 10
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:
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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) indicator in the first and second priorities that
supplements information from PSI independent Decodability Statistics
Metrics Block [RFC6990]; 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
These metrics are applicable to any type of RTP application that uses
the MPEG2 TS standard format for multimedia data; for example, MPEG4
over MPEG2 TS over RTP. This new block type can be useful for
measuring content stream or TS quality by checking TS header
information [ETSI] and identifying the existence, and characterizing
the severity, of bitstream packetization problems which may affect
users' perception of a service delivered over RTP; it may also be
useful for verifying the continued correct operation of an existing
system management tool.
2. Terminology
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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 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
decodability statistics metrics beyond the information carried in the
standard RTCP packet format and PSI independent Decodability Metrics
Block [RFC6990], which are measured at the receiving end of the RTP
stream. It contains counts of six 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 Program Association Table(PAT) errors
o PAT 2 errors
o Program Map Table(PMT) errors
o PMT 2 errors
o Packet Identifier(PID) errors
and continuous monitoring parameters necessary to ensure the
continuous decoding including:
o Cyclic Redundancy Check (CRC) errors
o Conditional Access Table (CAT) errors
In these parameters,scrambling may be considered. The other
parameters are ignored since they do not apply to all MPEG2
implementations. For further detailed information on these
parameters, see [ETSI].
The MPEG2 TS PSI Decodability Metrics Block has the following format:
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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=MTPD | Reserved | block length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| SSRC of source |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| begin_seq | end_seq |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| PAT_error_count | PAT_error_2_count |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| PMT_error_count | PMT_error_2_count |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| PID_error_count | CRC_error_count |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| CAT_error_count | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
block type (BT): 8 bits
The MPEG2 TS PSI Decodability Metrics Block is identified by the
constant <MTPD>.
Reserved: 8 bits
These bits are reserved. They MUST be set to zero by senders
ignored by receivers (See [RFC6709] section 4.2).
block length: 16 bits
The constant 6, 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.
SSRC of source: 32 bits
As defined in Section 4.1 of RFC 3611.
begin_seq: 16 bits
As defined in Section 4.1 of RFC 3611.
end_seq: 16 bits
As defined in Section 4.1 of RFC 3611.
PAT_error_count: 16 bits
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A count of the number of PAT errors that occurred in the above
sequence number interval. The program association table (PAT) is
the only packet with packet ID (PID) 0x 0000. A PAT error occurs
when: (1) a packet with PID 0x0000 does not occur at least every
0.5 seconds, or (2) a packet with PID 0x0000 does not contain a
table_id 0x00 (i.e., a PAT), or (3)Scrambling_control_field in the
TS packet header is not 00 for a packet with PID 0x0000. See
section 5.2.1 of [ETSI]. Every program within the MPEG TS stream
is listed in the PAT; if it is missing, then no programs can be
decoded.
The measured value is unsigned value. If the measurement is
unavailable, the value 0xFFFF MUST be reported. Note that
PAT_error_count and PAT_error_2_count MUST NOT be reported at the
same time in the same metric block. If PAT_error_count is
reported, PAT_error_2_count MUST be set to 0xFFFF.
PAT_error_2_count: 16 bits
A count of the number of PAT2 errors that occurred in the above
sequence number interval. A PAT2 error occurs when: (1) a packet
with PID 0x0000 containing table_id 0x00 does not occur at least
every 0.5 seconds,or (2) a packet with PID 0x0000 contains one
table with table_id other than 0x00, or (3)
Scrambling_control_field in the TS packet header is not 00 for a
packet with PID 0x0000. See section 5.2.1 of [ETSI].
The measured value is unsigned value. If the measurement is
unavailable, the value 0xFFFF MUST be reported. Note that
PAT_error_count and PAT_error_2_count MUST NOT be reported at the
same time in the same metric block. If PAT_error_2_count is
reported, PAT_error_count MUST be set to 0xFFFF.
PMT_error_count: 16 bits
A count of the number of PMT_errors that occurred in the above
sequence number interval. A PMT_error occurs when: (1) a packet
containing one table with table_id 0x02(i.e.,a PMT) does not occur
at least every 0.5s on the PID that is referred to in the PAT,
or(2) Scrambling_control_field in the TS packet header is not 00
for all packets with PID containing one table with table_id 0x02
(i.e. a PMT). See the section 5.2.1 of [ETSI].
The measured value is unsigned value. If the measurement is
unavailable, the value 0xFFFF MUST be reported. Note that
PMT_error_count and PMT_error_2_count MUST NOT be reported at the
same time in the same metric block. If PMT_error_count is
reported, PMT_error_2_count MUST be set to 0xFFFF.
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PMT_error_2_count: 16 bits
A count of the number of PMT2 errors that occurred in the above
sequence number interval. A PMT2_error occurs when: (1) a packet
containing table_id 0x02(i.e.,a PMT) does not occur at least every
0.5s on each program_map_PID which is referred to in the PAT, or
(2) Scrambling_control_field in the TS packet header is not 00 for
all packets containing one table with table_id 0x02 (i.e. a PMT)
on each program_map_PID which is referred to in the PAT. See
section 5.2.1 of [ETSI].
The measured value is unsigned value. If the measurement is
unavailable, the value 0xFFFF MUST be reported. Note that
PMT_error_count and PMT_error_2_count MUST NOT be reported at the
same time in the same metric block. If PMT_error_2_count is
reported, PMT_error_count MUST be set to 0xFFFF.
PID_error_count: 16 bits
A count of the number of PID_errors that occurred in the above
sequence number interval. A PID_error occurs when MPEG TS streams
are remultiplexed and any PID doesn't refer to an actual data
stream, as defined in the section 5.2.1 of [ETSI].
The measured value is unsigned value. If the measurement is
unavailable, the value 0xFFFF MUST be reported.
CRC_error_count: 16 bits
A count of the number of CRC_errors that occurred in the above
sequence number interval. A CRC_error occurs if data corruption
occurred in any of the following tables -- CAT, PAT, PMT, Network
Information Table (NIT), Event Information Table (EIT), Bouquet
Association Table (BAT), Service Description Table (SDT) or Time
Offset Table (TOT), as defined in the section 5.2.2 of [ETSI].
The measured value is unsigned value. If the measurement is
unavailable, the value 0xFFFF MUST be reported.
CAT_error_count: 16 bits
A count of the number of CAT_errors that occurred in the above
sequence number interval. A CAT_error occurs when: (1) a packet
with PID 0x0001 contains one table with table_id other than
0x01(i.e.,not a CAT), or (2) A packet does not contain one table
with table_id = 0x01 (i.e. a CAT) when scrambling is employed
((i.e., scrambling_control field is set as a value other than
00)). See the section 5.2.2 of [ETSI].
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The measured value is unsigned value. If the measurement is
unavailable, the value 0xFFFF MUST be reported.
Reserved: 16 bits
These bits are reserved. They MUST be set to zero by senders
ignored by receivers (See [RFC6709] section 4.2).
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).
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-tpd-block
xr-tpd-block = "ts-psi-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].
4.3. Usage Outside of Offer/Answer
For usage outside of Offer/Answer,refer to section 5.3 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 MTPD in the IANA " RTP
Control Protocol Extended Reports (RTCP XR) Block Type Registry " to
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the "MPEG2 Transport Stream PSI Decodability Statistics Metrics
Block".
[Note to RFC Editor: please replace MTPD 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-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:
RAI Area Directors <rai-ads@tools.ietf.org>
6. Security Considerations
This proposed RTCP XR report block introduces no new security
considerations beyond those described in RFC 3611.
7. References
7.1. 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.
[RFC4566] Handley, M., Jacobson, V., and C. Perkins, "SDP: Session
Description Protocol", RFC 4566, July 2006.
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7.2. 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.
[RFC6792] Wu, Q., Hunt, G., and P. Arden, "Guidelines for Use of the
RTP Monitoring Framework", RFC 6792, November 2012.
[RFC6990] Wu, Q., "RTP Control Protocol (RTCP) Extended Report (XR)
Block for MPEG2 Transport Stream (TS) Program Specific
Information (PSI) Independent Decodability Statistics
Metrics reporting", RFC 6990, May 2013.
Authors' Addresses
Jiangang Tong
Shanghai Research Institure of China Telecom Corporation Limited
No.1835,South Pudong Road
Shanghai 200122
China
Email: tongjg@sttri.com.cn
Claire Bi (editor)
Shanghai Research Institure of China Telecom Corporation Limited
No.1835,South Pudong Road
Shanghai 200122
China
Email: bijy@sttri.com.cn
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Roni Even
Gesher Erove Ltd
14 David Hamelech
Tel Aviv 64953
Israel
Email: ron.even.tlv@gmail.com
Qin Wu (editor)
Huawei
101 Software Avenue, Yuhua District
Nanjing, Jiangsu 210012
China
Email: bill.wu@huawei.com
Rachel Huang
Huawei
101 Software Avenue, Yuhua District
Nanjing, Jiangsu 210012
China
Email: rachel.huang@huawei.com
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