Network Working Group A. Clark
Internet-Draft Telchemy
Intended status: Standards Track Q. Wu
Expires: August 17, 2014 Huawei
R. Schott
Deutsche Telekom
G. Zorn
Network Zen
February 13, 2014

RTP Control Protocol (RTCP) Extended Report (XR) Blocks for MOS Metric Reporting
draft-ietf-xrblock-rtcp-xr-qoe-14

Abstract

This document defines an RTP Control Protocol (RTCP) Extended Report (XR) Block including two new segment types and associated SDP parameters that allow the reporting of mean opinion score (MOS) Metrics for use in a range of RTP applications.

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/.

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This Internet-Draft will expire on August 17, 2014.

Copyright Notice

Copyright (c) 2014 IETF Trust and the persons identified as the document authors. All rights reserved.

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Table of Contents

1. Introduction

1.1. MOS Metrics Report Block

This document defines a new block type to augment those defined in [RFC3611], for use in a range of RTP applications.

The new block type provides information on media quality using one of several standard metrics (i.e. Mean Opinion Score(MOS)).

The metrics belong to the class of application level metrics defined in [RFC6792].

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 guidelines for reporting block format using RTCP XR. The XR block type described in this document are in accordance with the guidelines in [RFC6390] and [RFC6792].

1.4. Applicability

The MOS Metrics Report Block can be used in any application of RTP for which QoE (Quality of Experience) measurement algorithms are defined.

The factors that affect real-time audio/video application quality can be split into two categories. The first category consists of transport-specific factors such as packet loss, delay and jitter (which also translates into losses in the playback buffer). The factors in the second category consists of content and codec related factors such as codec type and loss recovery technique, coding bit rate, packetization scheme, and content characteristics

Transport-specific factors may be insufficient to infer real time media quality as codec related parameters and the interaction between transport problems and application layer protocols can have a substantial effect on observed media quality. Media quality may be measured using algorithm that directly compare input and output media streams, or may be estimated using algorithms that model the interaction between media quality, protocol and encoded content. Media quality is commonly expressed in terms of Mean Opinion Scores (MOS) however is also represented by a range of indexes and other scores.

The measurement of media quality has a number of applications:

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].

The terminology used is

3. MoS Metrics Block

Multimedia application MOS Metric is commonly expressed as a MOS ("Mean Opinion Score"), MOS is usually on a scale from 1 to 5, in which 5 represents excellent and 1 represents unacceptable however can use other ranges (for example 1 to 11). The term "MOS score" originates from subjective testing, and is used to refer to the Mean of a number of individual Opinion Scores. There is therefore a well understood relationship between MOS and user experience, hence the industry commonly uses MOS as the scale for objective test results. Subjective tests can be used for measuring live network traffic however the use of objective or algorithmic measurement techniques allows much larger scale measurements to be made. Within the scope of this document, MOS scores are obtained using objective or estimation algorithms. ITU-T or ITU-R recommendations (e.g., [BS.1387-1][G.107][G.107.1][P.862][P.862.1][P.862.2][P.863][P.564][G.1082][P.1201.1][P.1201.2][P.1202.1][P.1202.2]) define methodologies for assessment of the performance of audio and video streams. Other international and national standards organizations such as EBU, ETSI, IEC and IEEE also define QoE algorithms and methodologies, and the intent of this document is not to restrict its use to ITU recommendations but to suggest that ITU recommendations be used where they are defined.

This block reports media quality in the form of a 1-5 MOS range however does not report QoE scores that include parameters outside the scope of the RTP stream, for example signaling performance, MTTR or other factors that may affect the overall user experience.

The MOS Metric reported in this block gives a numerical indication of the perceived quality of the received media stream, which is typically measured at the receiving end of the RTP stream. Instances of this Metrics Block refer by Synchronization source (SSRC) to the separate auxiliary Measurement Information block [RFC6776] which describes measurement periods in use (see RFC6776 section 4.2).

This Metrics Block relies on the measurement period in the Measurement Information block indicating the span of the report. Senders MUST send this block in the same compound RTCP packet as the measurement information block. Receivers MUST verify that the measurement period is received in the same compound RTCP packet as this Metrics Block. If not, this Metrics Block MUST be discarded.

3.1. Metric Block Structure

   
    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=MMB    | I |  Reserved |       Block Length            |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                        SSRC of source                         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                          Segment  1                           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                          Segment 2                            |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   ..................
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                          Segment n                            |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

The MOS Metrics Block has the following format:

3.2. Definition of Fields in MoS Metrics Block

Block type (BT): 8 bits


The MOS Metrics Block is identified by the constant <MMB>.

Interval Metric flag (I): 2 bits


This field is used to indicate whether the MOS Metrics are Sampled, Interval or Cumulative [RFC6792]:



In this document, MOS Metrics MAY be reported for intervals or for the duration of the media stream (cumulative). The value I=01, indicating a sampled value, MUST NOT be sent, and MUST be discarded when received.

Reserved: 6 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 ignored by the receiver (See RFC6709 section 4.2).

Block Length: 16 bits


The length of this report block in 32-bit words, minus one. For the MOS Metrics Block, the block length is variable length.

SSRC of source: 32 bits


As defined in Section 4.1 of [RFC3611].

Segment i: 32 bits


There are two segment types defined in this document: single stream Audio/Video per SSRC segment, multi-channel audio per SSRC segment. Multi-channel audio per SSRC segment is used to deal with the case where Multi-channel audios are carried in one RTP stream while single channel Audio/Video per SSRC segment is used to deal with the case where each media stream is identified by SSRC and sent in separate RTP stream. The leftmost bit of the segment determines its type. If the leftmost bit of the segment is zero, then it is single channel segment. If the leftmost bit is one, then it is multi-channel audio segment. Note that two segment types can not be present in the same metric block.

3.2.1. Single Channel audio/video per SSRC Segment

   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |S|     CAID      |    PT       |           MOS Value           |     
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Segment Type (S): 1 bit


This field is used to identify the segment type used in this report block. A zero identifies this as a single channel Audio/ Video per SSRC segment. Single channel means there is only one media stream carried in one RTP stream. The single channel Audio/ Video per SSRC segment can be used to report the MOS value associated with the media stream identified by SSRC. If there are multiple media streams and they want to use the single channel Audio/Video per SSRC segment to report the MOS value, they should be carried in the separate RTP streams with each identified by different SSRC. In this case, multiple MOS Metrics Blocks are required to report the MOS value corresponding to each media stream using single channel Audio/Video per SSRC segment in the same RTCP XR packet.

Calculation Algorithm ID (CAID) : 8 bits


The 8-bit CAID is the session specific reference to the calculation algorithm and associated qualifiers indicated in SDP (see Section 4.1) and used to compute QoE scores for this segment.

Payload Type (PT): 7 bits


MOS Metrics reporting depends on the payload format in use. This field identifies the RTP payload type in use during the reporting interval. The binding between RTP payload types and RTP payload formats is configured via a signalling protocol, for example an SDP offer/answer exchange. If the RTP payload type used is changed during an RTP session, separate reports SHOULD be sent for each RTP payload type, with corresponding measurement information blocks indicating the time period to which they relate.

Note that the use of this Report Block with MPEG Transport streams carried over RTP is undefined as each MPEG Transport stream may use distinct audio or video codecs and the indication of the encoding of these is within the MPEG Transport stream and does not use RTP payloads.

MOS Value: 16 bits


The estimated Mean Opinion Score for multimedia application performance is defined as including the effects of delay,loss, discard, jitter and other effects that would affect media quality. A 1-5 MOS score is multiplied by 10 and then represented in the 7:9 format. A value of 0xFFFE is a flag indicating that the measured value is out of range. A value of 0xFFFF is a flag indicating that the measurement is unavailable. Values other than 0xFFFE, 0xFFFF and the valid range defined above MUST NOT be sent and MUST be ignored by the receiving system.

3.2.2. Multi-Channel audio per SSRC Segment

   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |S|     CAID      |    PT       |CHID |        MOS Value        |     
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Segment Type (S): 1 bit


This field is used to identify the segment type used in this report block. A one identifies this as a multi-channel audio segment.

Calculation Algorithm ID (CAID) : 8 bits


The 8-bit CAID is the session specific reference to the calculation algorithm and associated qualifiers indicated in SDP (see Section 4.1) and used to compute QoE scores for this segment.

Payload Type (PT): 7 bits


As defined in Section 3.2.1 of this document

Channel Identifier (CHID): 3 bits


If multiple channels of audio are carried in one RTP stream, each channel of audio will be viewed as a independent channel(e.g., left channel audio, right channel audio). This field is used to identify each channel carried in the same media stream. The default Channel mapping follows static ordering rule described in the section 4.1 of [RFC3551]. However there are some payload formats that use different channel mappings, e.g., AC-3 audio over RTP [RFC4184] only follow AC-3 channel order scheme defined in [ATSC]. Enhanced AC-3 Audio over RTP [RFC4598] uses dynamic channel transform mechanism. In order that the appropriate channel mapping can be determined, MOS metrics reports need to be tied to an RTP payload format, i.e., including the payload type of the reported media according to [RFC6792] and using Payload Type to determine the appropriate channel mapping.

MOS Value: 13 bits


The estimated Mean Opinion Score for multimedia application performance includes the effects of delay,loss, discard, jitter and other effects that would affect multimedia quality. The estimated MOS value is multiplied by 10 and expressed in 7:6 format. A value of 0x1FFE is a flag indicating that the measured value is out of range. A value of 0x1FFF is a flag indicating that the measurement is unavailable. Values other than 0x1FFE, 0x1FFF and the valid range defined above MUST NOT be sent and MUST be ignored by the receiving system.

4. SDP Signaling

[RFC3611]defines the use of SDP (Session Description Protocol) [RFC4566] for signaling the use of 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 section augments the SDP [RFC4566] attribute "rtcp-xr" defined in [RFC3611] by providing an additional value of "xr-format" to signal the use of the report block defined in this document. Within the "xr-format", the syntax element "calgextmap" is an attribute as defined in [RFC4566] and used to signal the mapping of the local identifier (CAID) in the segment extension defined in section 3.2 to the calculation algorithm. Specific extensionattributes are defined by the specification that defines a specific extension name; there might be several.

xr-format =/ xr-mos-block
xr-mos-block = "mos-metrics" ["=" calgextmap *("," calgextmap)]
calgextmap =  mapentry "=" extensionname [SP extentionattributes]
direction = "sendonly" / "recvonly" / "sendrecv" / "inactive"
mapentry =  "calg:" 1*3 DIGIT ["/" direction]
                       ; Values in the range 1-255 are valid
                       ; if needed, 0 can be used to indicate that
                       ; an algorithm is rejected
extensionname = "P564";ITU-T P.564 Compliant Algorithm [P.564]
              / "G107";ITU-T G.107 [G.107]
              / "G107_1";ITU-T G.107.1 [G.107.1]
              / "TS101_329";ETSI TS 101 329-5 Annex E [ ETSI]
              /"JJ201_1 ";TTC JJ201.1 [TTC]
              /"P1201_1";ITU-T P.1201.2 [P.1201.1]
              /"P1201_2";ITU-T P.1201.2 [P.1201.2]
              /"P1202_1";ITU-T P.1202.1 [P.1202.1]
              /"P1202_2";ITU-T P.1202.2 [P.1202.2]
              /"P.862.2";ITU-T P.862.2 [P.862.2]
              /"P.863"; ITU-T P.863 [P.863]
              / non-ws-string
extensionattributes = mosref
                    /attributes-ext
mosref =  "mosref=" ("l"; lower resolution
                     /"m"; middle resolution
                     / "h";higher resolution
                    / non-ws-string)
attributes-ext = non-ws-string
SP = <Define in RFC5234>
non-ws-string  = 1*(%x21-FF)


a=calg:<value> ["/"<direction>] <name> [<extensionattributes>]

Each local identifier (CAID)of calculation algorithm used in the segment defined in the section 3.2 is mapped to a string using an attribute of the form: 

Example:
a=rtcp-xr:mos-metrics=calg:1=G107,calg:2=P1202_1

where <name> is a calculation algorithm name, as above, <value> is the local identifier (CAID)of the calculation algorithm associated with the segment defined in this document and is an integer in the valid range inclusive.

A usable mapping MUST use IDs in the valid range, and each ID in this range MUST be unique and used only once for each stream or each channel in the stream.

The mapping MUST be provided per media stream (in the media-level section(s) of SDP, i.e., after an "m=" line).

The syntax element "mosref" is referred to the media resolution relative reference and has three valules 'l','m','h'.(e.g., Narrowband (3.4kHz) Speech and Standard Definition (SD) or lower Resolution Video have 'l' resolution, Super Wideband (>14kHz) Speech or higher and High Definition (HD) or higher Resolution Video have 'h' Resolution, Wideband speech(7khz) and Video with resolution between SD and HD has 'm' resolution). MOS scores reported in the mos metrics block might vary with the MOS reference; For example, MOS values for narrowband, wideband, super wideband codecs occupy the same range but SHOULD be reported in different value. For video application, MOS scores for SD resolution, HD resolution video also occupy the same ranges and SHOULD be reported in different value.

4.2. Offer/Answer Usage

When SDP is used in offer-answer context, the SDP Offer/Answer usage defined in [RFC3611] applies. In the offer answer context, the signaling described above might be used in three ways:

A direction attribute MAY be included in a calgextmap; without it, the direction implicitly inherits, of course, from the RTCP stream direction.

Segment extensions, with their directions, MAY be signaled for an "inactive" stream. An extension direction SHOULD be compatible with the stream direction. If a segment extension in the SDP offer is marked as "sendonly" and the answerer desires to receive it, the extension MUST be marked as "recvonly" in the SDP answer. An answerer that has no desire to receive the extension or does not understand the extension SHOULD remove it from the SDP answer.

If a segment extension is marked as "recvonly" in the SDP offer and the answerer desires to send it, the extension MUST be marked as "sendonly" in the SDP answer. An answerer that has no desire to, or is unable to, send the extension SHOULD remove it from the SDP answer.

If a segment extension is offered as "sendrecv", explicitly or implicitly, and asymmetric behavior is desired, the SDP MAY be modified to modify or add direction qualifiers for that segment extension.

A mosref attribute and mos type attribute MAY be included in an calgextmap; without it, the mosref and most type attribute implicitly inherits, of course, from the name attribute (e.g., P.1201.1 [P.1201.1] indicates lower resolution used while P.1201.2 [P.1201.2] indicates higher resolution used) or payload type carried in the segment extension (e.g.,EVRC-WB [RFC5188] indicates using Wideband Codec). However not all payload types or MOS algorithm names indicate resolution to be used and mos type to be used. If an answerer receives an offer with an mosref attribute value it doesn't support (e.g.,the answerer only supports "l" and receives "h"from offerer), the answer SHOULD reject the mosref attribute value offered by the offerer.

If the answerer wishes to reject a mosref attribute offered by the offerer, it sets identifiers associated with segment extensions in the answer to the value in the range 4096-4351. The rejected answer MUST contain 'mosref ' attribute whose value is the value of the SDP offer.

Local identifiers in the valid range inclusive in an offer or answer must not be used more than once per media section. A session update MAY change the direction qualifiers of segment extensions under use. A session update MAY add or remove segment extension(s). Identifiers values in the valid range MUST NOT be altered (remapped).

If a party wishes to offer mutually exclusive alternatives, then multiple segment extensions with the same identifier in the (unusable) range 4096-4351 MAY be offered; the answerer SHOULD select at most one of the offered extensions with the same identifier, and remap it to a free identifier in the valid range, for that extension to be usable. Note that two segment types defined in section 3 are also two exclusive alternatives.

If more segment extensions are offered in the valid range, the answerer SHOULD choose those that are desired, and place the offered identifier value "as is" in the SDP answer.

Similarly, if more segment extensions are offered than can be fit in the valid range, identifiers in the range 4096-4351 MAY be offered; the answerer SHOULD choose those that are desired, and remap them to a free identifier in the valid range.

Example (port numbers, RTP profiles, payload IDs and rtpmaps, etc.
all omitted for brevity):

The offer:

Note that the range 4096-4351 for these negotiation identifiers is deliberately restricted to allow expansion of the range of valid identifiers in future. Segment extensions with an identifier outside the valid range cannot, of course, be used.

The answerer is interested in transmission P.1202.1 on lower resolution application, but doesn't support P.1201.1 on lower resolution application at all. It is interested in transmission G.107. It therefore adjusts the declarations:

a=rtcp-xr:mos-metrics=calg:1=P1202_l,calg:2=G107

5. IANA Considerations

New block types for RTCP XR are subject to IANA registration. For general guidelines on IANA considerations for RTCP XR, refer to [RFC3611].

5.1. New RTCP XR Block Type value

This document assigns the block type value MMB in the IANA " RTP Control Protocol Extended Reports (RTCP XR) Block Type Registry" to the "MOS Metrics Block".

[Note to RFC Editor: please replace MMB 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 "mos-metrics" in the " RTP Control Protocol Extended Reports (RTCP XR) Session Description Protocol (SDP) Parameters Registry".

5.3. The SDP calgextmap Attribute

Qin Wu
sunseawq@huawei.com

This section contains the information required by [RFC4566] for an SDP attribute.

5.4. New registry of calculation algorithms

Name             Name Description                  Reference    Type
=========   ===================================   ==========    ====
P564       ITU-T P.564 Compliant Algorithm        [P.564]        Voice
G107       ITU-T G.107                            [G.107]        Voice
TS101_329  ETSI TS 101 329-5 Annex E              [ETSI]         Voice
JJ201_1    TTC JJ201.1                            [TTC]          Voice
G107_1     ITU-T G.107.1                          [G.107.1]      Voice
P862       ITU-T P.862                            [P.862]        Voice
P862_2     ITU-T P.862.2                          [P.862.2]      Voice
P863       ITU-T P.863                            [P.863]        Voice
P1201_1    ITU-T P.1201.1                     [P.1201.1]      Multimedia
P1201_2    ITU-T P.1201.2                     [P.1201.2]      Multimedia
P1202_1    ITU-T P.1202.1                     [P.1202.1]         Video
P1202_2    ITU-T P.1202.2                     [P.1202.2]         Video

This document creates a new registry to be called "RTCP XR MOS Metric block - multimedia application Calculation Algorithm" as a sub- registry of the "RTP Control Protocol Extended Reports (RTCP XR) Block Type Registry". This registry applies to the multimedia session where each type of media are sent in a separate RTP stream and also applies to the session where Multi-channel audios are carried in one RTP stream. Policies for this new registry are as follows:

6. Security Considerations

The new RTCP XR report blocks proposed in this document introduces no new security considerations beyond those described in [RFC3611].

7. Authors

This draft merges ideas from two drafts addressing the MOS Metric Reporting issue. The authors of these drafts are listed below (in alphabetical order):

8. Acknowledgements

The authors gratefully acknowledge the comments and contributions made by Bruce Adams, Philip Arden, Amit Arora, Bob Biskner, Kevin Connor, Claus Dahm, Randy Ethier, Roni Even, Jim Frauenthal, Albert Higashi, Tom Hock, Shane Holthaus, Paul Jones, Rajesh Kumar, Keith Lantz, Mohamed Mostafa, Amy Pendleton, Colin Perkins, Mike Ramalho, Ravi Raviraj, Albrecht Schwarz, Tom Taylor, Bill Ver Steeg, David R Oran, Ted Lemon,Benoit Claise, Pete Resnick, Ali Begen and Hideaki Yamada.

9. References

9.1. Normative References

[RFC3611] Friedman, T., Caceres, R. and A. Clark, "RTP Control Protocol Extended Reports (RTCP XR)", RFC 3611, November 2003.
[RFC6776] Wu, Q., "Measurement Identity and information Reporting using SDES item and XR Block", RFC 6776, October 2012.
[RFC3550] Schulzrinne, H., "RTP: A Transport Protocol for Real-Time Applications", RFC 3550, July 2003.
[RFC3551] Schulzrinne, H. and S. Casner, "RTP Profile for Audio and Video Conferences with Minimal Control", RFC 3551, July 2003.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997.
[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.
[RFC5226] Narten, T., "Guidelines for Writing an IANA Considerations Section in RFCs", RFC 5226, May 2008.
[ATSC] U.S. Advanced Television Systems Committee (ATSC), "ATSC Standard: Digital Audio Compression (AC-3), Revision B", ATSC Doc A/52B, June 2005.

9.2. Informative References

[BS.1387-1] ITU-R, "Method for objective measurements of perceived audio quality", ITU-R Recommendation BS.1387-1, 2001.
[G.1082] ITU-T, "Measurement-based methods for improving the robustness of IPTV performance", ITU-T Recommendation G.1082, April 2009.
[P.564] ITU-T, "Conformance testing for narrowband Voice over IP transmission quality assessment models", ITU-T Recommendation P.564, July 2006.
[G.107] ITU-T, "The E Model, a computational model for use in transmission planning", ITU-T Recommendation G.107, April 2009.
[G.107.1] ITU-T, "Wideband E-model", ITU-T Recommendation G.107.1, December 2011.
[ETSI] ETSI, "Quality of Service (QoS) measurement methodologies", ETSI TS 101 329-5 V1.1.1, November 2000.
[P.1201.1] ITU-T, "Parametric non-intrusive assessment of audiovisual media streaming quality - lower resolution application area", ITU-T Recommendation P.1201.1, October 2012.
[P.1201.2] ITU-T, "Parametric non-intrusive assessment of audiovisual media streaming quality - higher resolution application area", ITU-T Recommendation P.1201.2, October 2012.
[P.1202.1] ITU-T, "Parametric non-intrusive bitstream assessment of video media streaming quality - lower resolution application area", ITU-T Recommendation P.1202.1, October 2012.
[P.1202.2] ITU-T, "Parametric non-intrusive bitstream assessment of video media streaming quality - higher resolution application area", ITU-T Recommendation P.1202.2, May 2013.
[P.862] ITU-T, "Perceptual evaluation of speech quality (PESQ): An objective method for end-to-end speech quality assessment of narrow-band telephone networks and speech codecs", ITU-T Recommendation P.862, Febuary 2001.
[P.862.1] ITU-T, "Mapping function for transforming P.862 raw result scores to MOS-LQO", ITU-T Recommendation P.862.1, November 2003.
[P.862.2] ITU-T, "Wideband extension to Recommendation P.862 for the assessment of wideband telephone networks and speech codecs", ITU-T Recommendation P.862.2, November 2007.
[P.863] ITU-T, "Perceptual objective listening quality assessment", ITU-T Recommendation P.863, January 2011.
[TTC] TTC 201.01 (Japan), "A method for speech quality assessment for Voice over IP", .
[RFC6792] Wu, Q., "Monitoring Architectures for RTP", RFC 6792, November 2012.
[RFC6390] Clark, A. and B. Claise, "Framework for Performance Metric Development", RFC 6390, October 2011.
[RFC4598] Link, B., "Real-time Transport Protocol (RTP) Payload Format for Enhanced AC-3 (E-AC-3) Audio", RFC 4598, July 2006.
[RFC4184] Link, B., Hager, T. and J. Flaks, "RTP Payload Format for AC-3 Audio", RFC 4184, October 2005.
[RFC5188] Desineni, H. and Q. Xie, "RTP Payload Format for the Enhanced Variable Rate Wideband Codec (EVRC-WB) and the Media Subtype Updates for EVRC-B Codec", RFC 5188, February 2008.

Appendix A. Metrics represented using RFC6390 Template

RFC EDITOR NOTE: please change XXXX in [RFCXXXX] by the new RFC number, when assigned.

  1. MOS Value Metric

  2. Segment Type Metric

  3. Calculation Algorithm Identifier Metric

  4. Payload Type Metric

  5. Channel Identifier Metric

Appendix B. Change Log

B.1. draft-ietf-xrblock-rtcp-xr-qoe-14

The following are the major changes compared to previous version:

B.2. draft-ietf-xrblock-rtcp-xr-qoe-10

The following are the major changes compared to previous version:

B.3. draft-ietf-xrblock-rtcp-xr-qoe-09

The following are the major changes compared to previous version:

B.4. draft-ietf-xrblock-rtcp-xr-qoe-08

The following are the major changes compared to previous version:

B.5. draft-ietf-xrblock-rtcp-xr-qoe-07

The following are the major changes compared to previous version:

B.6. draft-ietf-xrblock-rtcp-xr-qoe-06

The following are the major changes compared to previous two versions:

B.7. draft-ietf-xrblock-rtcp-xr-qoe-04

The following are the major changes compared to previous version:

B.8. draft-ietf-xrblock-rtcp-xr-qoe-03

The following are the major changes compared to previous version:

B.9. draft-ietf-xrblock-rtcp-xr-qoe-02

The following are the major changes compared to previous version:

B.10. draft-ietf-xrblock-rtcp-xr-qoe-01

The following are the major changes compared to previous version:

B.11. draft-ietf-xrblock-rtcp-xr-qoe-00

The following are the major changes compared to previous version:

Authors' Addresses

Alan Clark Telchemy Incorporated 2905 Premiere Parkway, Suite 280 Duluth, GA 30097 USA EMail: alan.d.clark@telchemy.com
Qin Wu Huawei 101 Software Avenue, Yuhua District Nanjing, Jiangsu 210012 China EMail: sunseawq@huawei.com
Roland Schott Deutsche Telekom Heinrich-Hertz-Straße 3-7 Darmstadt, 64295 Germany EMail: Roland.Schott@telekom.de
Glen Zorn Network Zen 77/440 Soi Phoomjit, Rama IV Road Phra Khanong, Khlong Toie Bangkok, 10110 Thailand Phone: +66 (0) 87 502 4274 EMail: gwz@net-zen.net