Internet Engineering Task Force (IETF) J. Tong
Request for Comments: 7380 C. Bi, Ed.
Category: Standards Track China Telecom
ISSN: 2070-1721 R. Even
Q. Wu, Ed.
R. Huang
Huawei
November 2014
Internet Engineering Task Force (IETF) J. Tong
Request for Comments: 7380 C. Bi, Ed.
Category: Standards Track China Telecom
ISSN: 2070-1721 R. Even
Q. Wu, Ed.
R. Huang
Huawei
November 2014
RTP Control Protocol (RTCP) Extended Report (XR) Block for MPEG2 Transport Stream (TS) Program Specific Information (PSI) Decodability Statistics Metrics Reporting
用于MPEG2传输流（TS）程序特定信息（PSI）可解码性统计指标报告的RTP控制协议（RTCP）扩展报告（XR）块
Abstract
摘要
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 (PSI) carried in MPEG TS.
MPEG2传输流（TS）是用于多媒体数据传输和存储的标准容器格式。RTP上的单播/多播MPEG2 TS广泛部署在IPTV系统中。本文档定义了一个RTP控制协议（RTCP）扩展报告（XR）块，该块允许报告与通过RTP传输MPEG2 TS相关的MPEG2 TS可解码性统计指标。RTCP XR块中指定的度量与MPEG TS中携带的节目特定信息（PSI）相关。
Status of This Memo
关于下段备忘
This is an Internet Standards Track document.
这是一份互联网标准跟踪文件。
This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Further information on Internet Standards is available in Section 2 of RFC 5741.
本文件是互联网工程任务组（IETF）的产品。它代表了IETF社区的共识。它已经接受了公众审查，并已被互联网工程指导小组（IESG）批准出版。有关互联网标准的更多信息，请参见RFC 5741第2节。
Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at http://www.rfc-editor.org/info/rfc7380.
有关本文件当前状态、任何勘误表以及如何提供反馈的信息，请访问http://www.rfc-editor.org/info/rfc7380.
Copyright Notice
版权公告
Copyright (c) 2014 IETF Trust and the persons identified as the document authors. All rights reserved.
版权所有（c）2014 IETF信托基金和确定为文件作者的人员。版权所有。
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.
本文件受BCP 78和IETF信托有关IETF文件的法律规定的约束(http://trustee.ietf.org/license-info)自本文件出版之日起生效。请仔细阅读这些文件，因为它们描述了您对本文件的权利和限制。从本文件中提取的代码组件必须包括信托法律条款第4.e节中所述的简化BSD许可证文本，并提供简化BSD许可证中所述的无担保。
Table of Contents
目录
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 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 .............................................9
5.1. New RTCP XR Block Type Value ...............................9
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 .................................................11
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 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 .............................................9
5.1. New RTCP XR Block Type Value ...............................9
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 .................................................11
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:
欧洲电信标准协会（ETSI）定义了一套语法和信息一致性测试以及相应的指标[ETSI]，建议用于监测MPEG2传输流[ISO-IEC.13818-1.2007]。测试和相应的指标根据优先级进行分组：
First priority: Necessary for decodability (basic monitoring)
第一优先级：可分解性所需（基本监测）
Second priority: Recommended for continuous or periodic monitoring
第二优先级：建议用于连续或定期监测
Third priority: Recommended for application-dependent monitoring
第三优先级：建议用于依赖于应用程序的监视
This memo defines a new block type for use with MPEG2 Transport Streams [ISO-IEC.13818-1.2007] to augment those defined in [RFC3611]. The new block type supports reporting of the number of occurrences of each Program Specific Information (PSI) indicator in the first and second priorities listed in Sections 5.2.1 and 5.2.2, respectively, of [ETSI]. The third priority indicators are not supported. The metrics defined here supplement information from the PSI-Independent Decodability Statistics Metrics Block [RFC6990].
本备忘录定义了用于MPEG2传输流[ISO-IEC.13818-1.2007]的新块类型，以扩充[RFC3611]中定义的块类型。新的块类型支持在[ETSI]第5.2.1节和第5.2.2节分别列出的第一和第二优先级中报告每个程序特定信息（PSI）指示器的出现次数。不支持第三优先级指标。此处定义的度量补充了PSI独立可解性统计度量块[RFC6990]中的信息。
The use of RTCP for reporting is defined in [RFC3550]. [RFC3611] defines 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].
[RFC3550]中定义了使用RTCP进行报告。[RFC3611]定义了使用RTCP扩展报告（XR）进行报告的可扩展结构。本文档定义了一个新的扩展报告块，用于[RFC3550]和[RFC3611]。
The Performance Metrics Framework [RFC6390] provides guidance on the definition and specification of performance metrics. The RTP Monitoring Architectures [RFC6792] provides guidelines for RTCP XR block formats. The new report block described in this memo is in compliance with the monitoring architecture specified in [RFC6792] and the Performance Metrics Framework [RFC6390].
性能指标框架[RFC6390]提供了有关性能指标定义和规范的指导。RTP监控体系结构[RFC6792]提供了RTCP XR块格式的指南。本备忘录中描述的新报告块符合[RFC6792]和性能度量框架[RFC6390]中规定的监控体系结构。
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
这些指标适用于对多媒体数据使用MPEG2 TS标准格式的任何类型的RTP应用程序，例如，MPEG4 over MPEG2 TS over RTP。这种新的块类型可用于通过检查TS头信息[ETSI]和识别存在（和特征化）来测量内容流或TS质量
the severity) of bitstream packetization problems that 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.
可能影响用户对通过RTP提供的服务的感知的比特流打包问题的严重性）。它还可用于验证现有系统管理工具的持续正确操作。
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].
本文件中的关键词“必须”、“不得”、“要求”、“应”、“不应”、“应”、“不应”、“建议”、“可”和“可选”应按照RFC 2119[RFC2119]中所述进行解释。
ETSI TR 101 290 [ETSI] generally defines indicators related to error events whereas the XR block defined in this document contains counts of occurrences of the [ETSI] indicators. 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 Statistics Metrics Block [RFC6990], which are measured at the receiving end of the RTP stream. It contains counts of seven metrics defined in ETSI TR 101 290 [ETSI]. Information is reported about basic monitoring parameters necessary to ensure that the TS can be decoded, including:
ETSI TR 101 290[ETSI]通常定义与错误事件相关的指示器，而本文档中定义的XR块包含[ETSI]指示器的出现次数。本文档中定义的块报告了MPEG2 TS PSI可解性统计指标，超出了标准RTCP数据包格式和PSI独立可解性统计指标块[RFC6990]中携带的信息，这些指标在RTP流的接收端测量。它包含ETSI TR 101 290[ETSI]中定义的七个指标的计数。报告了确保TS可解码所需的基本监测参数信息，包括：
o Program Association Table (PAT) errors
o 程序关联表（PAT）错误
o PAT2 errors
o PAT2错误
o Program Map Table (PMT) errors
o 程序映射表（PMT）错误
o PMT2 errors
o PMT2误差
o Packet Identifier (PID) errors
o 数据包标识符（PID）错误
Information is also reported about continuous monitoring parameters necessary to ensure continuous decoding, including:
还报告了确保连续解码所需的连续监测参数信息，包括：
o Cyclic Redundancy Check (CRC) errors
o 循环冗余校验（CRC）错误
o Conditional Access Table (CAT) errors
o 条件访问表（CAT）错误
In these parameters, PAT2 errors and PMT2 errors are actually replacements for and improvements on PAT errors and PMT errors, respectively, and are therefore preferred in future implementations. In addition, measurement results for some of these parameters (e.g., PAT errors or PMT errors) may be different based on whether
在这些参数中，PAT2错误和PMT2错误实际上分别是PAT错误和PMT错误的替代和改进，因此在未来的实现中是首选的。此外，某些参数（例如PAT误差或PMT误差）的测量结果可能会因以下情况而有所不同：
scrambling is employed. The other parameters defined in Section 5 of [ETSI] are ignored since they do not apply to all MPEG2 implementations. For further detailed information on these parameters, see [ETSI].
采用加扰法。[ETSI]第5节中定义的其他参数被忽略，因为它们不适用于所有MPEG2实现。有关这些参数的更多详细信息，请参见[ETSI]。
The MPEG2 TS PSI Decodability Metrics Block has the following format:
MPEG2 TS PSI可分解性度量块具有以下格式：
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=32 | 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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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=32 | 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
块类型（BT）：8位
The MPEG2 TS PSI Decodability Metrics Block is identified by the constant 32;.
MPEG2 TS PSI可解性度量块由常数32；标识；。
Reserved: 8 bits
保留：8位
These bits are reserved. They MUST be set to zero by senders ignored by receivers (see Section 4.2 of [RFC6709]).
这些位是保留的。接收方忽略的发送方必须将其设置为零（见[RFC6709]第4.2节）。
block length: 16 bits
块长度：16位
The constant 6, in accordance with the definition of this field in Section 3 of [RFC3611]. The block MUST be discarded if the block length is set to a different value.
常数6，符合[RFC3611]第3节中该字段的定义。如果块长度设置为不同的值，则必须丢弃该块。
Synchronization Source (SSRC) of source: 32 bits
源的同步源（SSRC）：32位
As defined in Section 4.1 of [RFC3611].
如[RFC3611]第4.1节所定义。
begin_seq: 16 bits
开始顺序：16位
As defined in Section 4.1 of [RFC3611].
如[RFC3611]第4.1节所定义。
end_seq: 16 bits
结束顺序：16位
As defined in Section 4.1 of [RFC3611].
如[RFC3611]第4.1节所定义。
PAT_error_count: 16 bits
PAT_错误计数：16位
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 Identifier (PID) 0x0000. A PAT error occurs when (1) a packet with PID 0x0000 does not occur at least every 0.5 seconds, (2) a packet with PID 0x0000 does not contain table_id 0x00 (i.e., a PAT), or (3) the 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.
在上述序列号间隔内发生的PAT错误数的计数。程序关联表（PAT）是唯一具有数据包标识符（PID）0x0000的数据包。当（1）PID为0x0000的数据包至少每0.5秒不出现一次，（2）PID为0x0000的数据包不包含表id 0x00（即PAT）或（3）对于PID为0x0000的数据包，TS数据包头中的加扰控制字段不是00时，会发生PAT错误。见[ETSI]第5.2.1节。在PAT中列出MPEG-TS流中的每个节目；如果丢失，则无法解码任何程序。
The measured value is an unsigned value. If the measurement is unavailable, then the value 0xFFFF MUST be reported. NOTE 1 of the table in Section 5.2.1 of [ETSI] recommends using PAT_error_2_count. Upon reception, if PAT_error_2_count is available (that is, other than 0xFFFF), then receivers MUST ignore PAT_error_count.
测量值为无符号值。如果测量不可用，则必须报告值0xFFFF。[ETSI]第5.2.1节表中的注释1建议使用PAT_错误_2_计数。接收时，如果PAT_error_2_count可用（即，0xFFFF除外），则接收机必须忽略PAT_error_count。
PAT_error_2_count: 16 bits
PAT_错误_2_计数：16位
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, (2) a packet with PID 0x0000 contains a table with a table_id other than 0x00, or (3) the Scrambling_control_field in the TS packet header is not 00 for a packet with PID 0x0000. See Section 5.2.1 of [ETSI].
在上述序列号间隔内发生的PAT2错误数的计数。当（1）包含表_id 0x00的PID 0x0000数据包未至少每0.5秒出现一次，（2）PID 0x0000数据包包含表_id非0x00的数据表，或（3）对于PID 0x0000数据包，TS数据包头中的加扰控制_字段不是00时，会发生PAT2错误。见[ETSI]第5.2.1节。
The measured value is an unsigned value. If the measurement is unavailable, then the value 0xFFFF MUST be reported.
测量值为无符号值。如果测量不可用，则必须报告值0xFFFF。
PMT_error_count: 16 bits
PMT_错误_计数：16位
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 a table with table_id 0x02 (i.e., a PMT) does not occur at least every 0.5 seconds on the PID that is referred to in the PAT or (2) the Scrambling_control_field in the TS packet header is not 00 for all packets with PID containing a table with table_id 0x02 (i.e., a PMT). See Section 5.2.1 of [ETSI].
在上述序列号间隔内发生的PMT错误数的计数。当（1）包含表_id 0x02的表的数据包（即，PMT）在PAT中引用的PID上没有至少每0.5秒发生一次，或者（2）对于包含表_id 0x02的表（即，PMT）的PID的所有数据包，TS数据包头中的加扰控制字段不是00时，会发生PMT_错误。见[ETSI]第5.2.1节。
The measured value is an unsigned value. If the measurement is unavailable, the value 0xFFFF MUST be reported. NOTE 2 of the table in Section 5.2.1 of [ETSI] recommends using PMT_error_2_count. Upon reception, if PMT_error_2_count is available (that is, other than 0xFFFF), then receivers MUST ignore PMT_error_count.
测量值为无符号值。如果测量不可用，则必须报告值0xFFFF。[ETSI]第5.2.1节表中的注2建议使用PMT_误差_2_计数。接收时，如果PMT_错误_2_计数可用（即除0xFFFF外），则接收器必须忽略PMT_错误_计数。
PMT_error_2_count: 16 bits
PMT_错误_2_计数：16位
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 0.5 seconds on each program_map_PID that is referred to in the PAT or (2) the Scrambling_control_field in the TS packet header is not 00 for all packets containing a table with table_id 0x02 (i.e., a PMT) on each program_map_PID that is referred to in the PAT. See Section 5.2.1 of [ETSI].
在上述序列号间隔内发生的PMT2错误数的计数。当（1）在PAT中引用的每个程序映射PID上，包含表id 0x02（即PMT）的数据包没有至少每0.5秒出现一次，或者（2）对于包含表id 0x02（即PMT）的表的所有数据包，TS数据包头中的加扰控制字段不是00时，就会发生PMT2\U错误在PAT中提及的每个程序上。见[ETSI]第5.2.1节。
The measured value is an unsigned value. If the measurement is unavailable, then the value 0xFFFF MUST be reported.
测量值为无符号值。如果测量不可用，则必须报告值0xFFFF。
PID_error_count: 16 bits
PID_错误_计数：16位
A count of the number of PID errors that occurred in the above sequence number interval. A PID error occurs when no data stream is present corresponding to a given PID. This may be caused by multiplexing or demultiplexing, then remultiplexing. See Section 5.2.1 of [ETSI].
在上述序列号间隔内发生的PID错误数的计数。当没有与给定PID对应的数据流时，会发生PID错误。这可能是由多路复用或解多路复用，然后再重新多路复用引起的。见[ETSI]第5.2.1节。
The measured value is an unsigned value. If the measurement is unavailable, then the value 0xFFFF MUST be reported.
测量值为无符号值。如果测量不可用，则必须报告值0xFFFF。
CRC_error_count: 16 bits
CRC\u错误\u计数：16位
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 Section 5.2.2 of [ETSI].
在上述序列号间隔内发生的CRC错误数的计数。如[ETSI]第5.2.2节所述，如果下列任何表格中发生数据损坏，则会发生CRC_错误：CAT、PAT、PMT、网络信息表（NIT）、事件信息表（EIT）、花束关联表（BAT）、服务描述表（SDT）或时间偏移表（TOT）。
The measured value is an unsigned value. If the measurement is unavailable, then the value 0xFFFF MUST be reported.
测量值为无符号值。如果测量不可用，则必须报告值0xFFFF。
CAT_error_count: 16 bits
类别错误计数：16位
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 a table with a table_id other than 0x01 (i.e., not a CAT) or (2) a packet does not contain a table with table_id = 0x01 (i.e., a CAT) when scrambling is employed (i.e., the Scrambling_control_field is set as a value other than 00). See Section 5.2.2 of [ETSI].
在上述序列号间隔内发生的CAT错误数的计数。当（1）PID为0x0001的数据包包含表id为0x01以外的表（即非CAT）或（2）当采用加扰时，数据包不包含表id为0x01（即CAT）的表（即加扰控制字段设置为00以外的值）时，会发生CAT错误。见[ETSI]第5.2.2节。
The measured value is an unsigned value. If the measurement is unavailable, then the value 0xFFFF MUST be reported.
测量值为无符号值。如果测量不可用，则必须报告值0xFFFF。
Reserved: 16 bits
保留：16位
These bits are reserved. They MUST be set to zero by senders ignored by receivers (see Section 4.2 of [RFC6709]).
这些位是保留的。接收方忽略的发送方必须将其设置为零（见[RFC6709]第4.2节）。
[RFC3611] defines the use of the Session Description Protocol (SDP)
[RFC4566] for signaling the use of RTCP XR blocks. However, XR
blocks MAY be used without prior signaling (see Section 5 of
[RFC3611]).
[RFC3611] defines the use of the Session Description Protocol (SDP)
[RFC4566] for signaling the use of RTCP XR blocks. However, XR
blocks MAY be used without prior signaling (see Section 5 of
[RFC3611]).
This session augments the SDP attribute "rtcp-xr" defined in Section 5.1 of [RFC3611] by providing an additional value of "xr-format" to signal the use of the report block defined in this document. The ABNF [RFC5234] syntax is as follows:
此会话通过提供附加值“xr format”来表示使用本文档中定义的报告块，从而增强[RFC3611]第5.1节中定义的SDP属性“rtcp xr”。ABNF[RFC5234]语法如下：
xr-format =/ xr-tpd-block
xr format=/xr tpd块
xr-tpd-block = "ts-psi-decodability"
xr-tpd-block = "ts-psi-decodability"
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 parameters, refer to Section 5.2 of [RFC3611].
在提供/应答上下文中使用SDP时，[RFC3611]中为单边“rtcp xr”属性参数定义的SDP提供/应答用法适用。有关单边参数的报价/应答的详细用法，请参阅[RFC3611]第5.2节。
For usage outside of Offer/Answer, refer to Section 5.3 of [RFC3611].
有关报价/应答之外的用途，请参阅[RFC3611]第5.3节。
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].
RTCP XR的新报告块类型需要IANA注册。有关RTCP XR IANA分配的一般指南，请参阅[RFC3611]第6.2节。
This document assigns the block type value 32 "MPEG2 Transport Stream PSI Decodability Statistics Metrics Block" in the "RTCP XR Block Type" subregistry of the IANA "RTP Control Protocol Extended Reports (RTCP XR) Block Type Registry".
本文档在IANA“RTP控制协议扩展报告（RTCP XR）块类型注册表”的“RTCP XR块类型”子区中分配块类型值32“MPEG2传输流PSI可解码性统计数据块”。
This document also registers a new parameter "ts-psi-decodability" in the "RTCP XR SDP Parameters" subregistry of the "RTP Control Protocol Extended Reports (RTCP XR) Session Description Protocol (SDP) Parameters Registry".
本文档还在“RTP控制协议扩展报告（RTCP XR）会话描述协议（SDP）参数注册表”的“RTCP XR SDP参数”子域中注册了一个新参数“ts psi可解码性”。
The contact information for the registrations is:
注册的联系信息为：
RAI Area Directors <rai-ads@tools.ietf.org>
RAI Area Directors <rai-ads@tools.ietf.org>
This proposed RTCP XR block introduces no new security considerations beyond those described in [RFC3611] and [RFC6990].
除了[RFC3611]和[RFC6990]中所述的安全注意事项外，拟议的RTCP XR块未引入任何新的安全注意事项。
[ETSI] ETSI, "Digital Video Broadcasting (DVB); Measurement guidelines for DVB systems", ETSI TR 101 290, June 2014.
[ETSI]ETSI，“数字视频广播（DVB）；DVB系统的测量指南”，ETSI TR 101 290，2014年6月。
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997, <http://www.rfc-editor.org/info/rfc2119>.
[RFC2119]Bradner，S.，“RFC中用于表示需求水平的关键词”，BCP 14，RFC 2119，1997年3月<http://www.rfc-editor.org/info/rfc2119>.
[RFC3550] Schulzrinne, H., "RTP: A Transport Protocol for Real-Time Applications", RFC 3550, July 2003, <http://www.rfc-editor.org/info/rfc3550>.
[RFC3550]Schulzrinne，H.，“RTP：实时应用的传输协议”，RFC3550，2003年7月<http://www.rfc-editor.org/info/rfc3550>.
[RFC3611] Friedman, T., Caceres, R., and A. Clark, "RTP Control Protocol Extended Reports (RTCP XR)", RFC 3611, November 2003, <http://www.rfc-editor.org/info/rfc3611>.
[RFC3611]Friedman，T.，Caceres，R.，和A.Clark，“RTP控制协议扩展报告（RTCP XR）”，RFC 36112003年11月<http://www.rfc-editor.org/info/rfc3611>.
[RFC4566] Handley, M., Jacobson, V., and C. Perkins, "SDP: Session Description Protocol", RFC 4566, July 2006, <http://www.rfc-editor.org/info/rfc4566>.
[RFC4566]Handley，M.，Jacobson，V.，和C.Perkins，“SDP：会话描述协议”，RFC4566，2006年7月<http://www.rfc-editor.org/info/rfc4566>.
[RFC5234] Crocker, D. and P. Overell, "Augmented BNF for Syntax Specifications: ABNF", STD 68, RFC 5234, January 2008, <http://www.rfc-editor.org/info/rfc5234>.
[RFC5234]Crocker，D.和P.Overell，“语法规范的扩充BNF:ABNF”，STD 68，RFC 5234，2008年1月<http://www.rfc-editor.org/info/rfc5234>.
[ISO-IEC.13818-1.2007] ISO/IEC, "Information technology - Generic coding of moving pictures and associated audio information - Part 1: Systems", ISO International Standard 13818-1, 2013.
[ISO-IEC.13818-1.2007]ISO/IEC，“信息技术-运动图像和相关音频信息的通用编码-第1部分：系统”，ISO国际标准13818-11913。
[RFC6390] Clark, A. and B. Claise, "Guidelines for Considering New Performance Metric Development", BCP 170, RFC 6390, October 2011, <http://www.rfc-editor.org/info/rfc6390>.
[RFC6390]Clark，A.和B.Claise，“考虑新绩效指标开发的指南”，BCP 170，RFC 63902011年10月<http://www.rfc-editor.org/info/rfc6390>.
[RFC6709] Carpenter, B., Aboba, B., and S. Cheshire, "Design Considerations for Protocol Extensions", RFC 6709, September 2012, <http://www.rfc-editor.org/info/rfc6709>.
[RFC6709]Carpenter，B.，Aboba，B.和S.Cheshire，“协议扩展的设计考虑”，RFC 6709，2012年9月<http://www.rfc-editor.org/info/rfc6709>.
[RFC6792] Wu, Q., Hunt, G., and P. Arden, "Guidelines for Use of the RTP Monitoring Framework", RFC 6792, November 2012, <http://www.rfc-editor.org/info/rfc6792>.
[RFC6792]Wu，Q.，Hunt，G.和P.Arden，“RTP监控框架的使用指南”，RFC 67922012年11月<http://www.rfc-editor.org/info/rfc6792>.
[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, <http://www.rfc-editor.org/info/rfc6990>.
[RFC6990]Wu，Q.“MPEG2传输流（TS）程序特定信息（PSI）独立可解码性统计指标报告的RTP控制协议（RTCP）扩展报告（XR）块”，RFC 69902013年5月<http://www.rfc-editor.org/info/rfc6990>.
Authors' Addresses
作者地址
Jiangang Tong Shanghai Research Institute of China Telecom Corporation Limited No. 1835, South Pudong Road Shanghai 200122 China
中国电信股份有限公司上海研究院上海浦东南路1835号，邮编：200122
EMail: tongjg@sttri.com.cn
EMail: tongjg@sttri.com.cn
Claire Bi (editor) Shanghai Research Institure of China Telecom Corporation Limited No. 1835, South Pudong Road Shanghai 200122 China
Claire Bi（编辑）中国电信股份有限公司上海研究院，地址：中国上海市浦东南路1835号，邮编：200122
EMail: bijy@sttri.com.cn
EMail: bijy@sttri.com.cn
Roni Even Huawei 14 David Hamelech Tel Aviv 64953 Israel
Roni甚至华为14 David Hamelech特拉维夫64953以色列
EMail: roni.even@mail01.huawei.com
EMail: roni.even@mail01.huawei.com
Qin Wu (editor) Huawei 101 Software Avenue, Yuhua District Nanjing, Jiangsu 210012 China
秦武（编辑）中国江苏省南京市雨花区华为软件大道101号210012
EMail: bill.wu@huawei.com
EMail: bill.wu@huawei.com
Rachel Huang Huawei 101 Software Avenue, Yuhua District Nanjing, Jiangsu 210012 China
中国江苏省南京市雨花区华为软件大道101号，邮编：210012
EMail: rachel.huang@huawei.com
EMail: rachel.huang@huawei.com