The first meeting of ITU-T Study Group 12 (Performance, QoS and QoE) in the
2009-2012 study period, convened by TSB Collective letter 1/12 of 5 January
2009, took place in Geneva, from 10 to 19 March 2009. There was a significant
increase in the number of attendees at this meeting, especially those from
developing countries. The meeting was transacted without any paper.
Mandate of Study Group 12
Study Group 12 (Performance, QoS and QoE) is responsible for Recommendations
on performance, quality of service (QoS) and quality of experience (QoE) for the
full spectrum of terminals, networks and services ranging from speech over fixed
circuit-based networks to multimedia applications over networks that are mobile
and packet based. Included in this scope are the operational aspects of
performance, QoS and QoE.
A special focus is given to interoperability to ensure end-to-end users'
Study Group 12 is the Lead study group on quality of service and quality of
2 Organization of the Study Group 12
At its first meeting SG12 decided to keep the previous structure having three
working parties. Question 1/12 was allocated directly to the SG12 Plenary.
The mandate of each working party and the related questions are as follows:
2.1 WP 1 - Terminals and multimedia subjective assessment
WP1/12 works on transmission characteristics of terminals for fixed
circuit-switched, mobile and packet-switched (IP) networks and the related
telephonometric methodologies, as well as analysis methods using complex
measurement signals. Hands-free communication in vehicles is an important study
item. Also addressed are methods, tools and test plans for the subjective
assessment of speech, audio and audiovisual quality interactions.
Questions: 3, 4, 5, 6 and 7/12
2.2 WP 2 - Objective models and tools for multimedia quality
It is the purpose of WP 2/12 to cover the end-to-end transmission performance
of networks, terminals and their interactions, in relation to the perceived
quality and its objective assessment as well as guidance and modelling in the
field of transmission planning. This includes beside perceptual-based objective
methods also parametric models and a framework for diagnostic functions.
Questions: 8, 9, 10, 14, 15 and 16/12
2.3 WP 3 - Multimedia QoS and QoE
WP3/12 is responsible for conducting studies leading to new Recommendations
related to multimedia Quality of Service (QoS) and Quality of Experience (QoE)
in emerging networks. This includes operational aspects of QoS/QoE, end to end
interworking and traffic management, identification of KPIs and QoS metrics for
different services, multimedia performance assessment methods and models, and
fundamental performance criteria for packet-based networks.
Questions: 2, 11, 12, 13 and 17/12.
3.1 Results of the meeting of Working Party 1/12
The foreseen evolution of activities is to consider bandwidth extension and
binaural perception and this is reflected in the work plan of Q4, 5 and 6.
The focus group Carcom provided a first draft of the future recommendations
on wideband hands free communications in vehicles, that it is planned to be
finalised during the next SG12.
The next meetings of FG CarCom are:
- - June 17 -18, 2009, Paris, France.
- - September 3-4, 2009, Gotenbörg,
Moreover, ITU-T/FG CarCom is planning to organize a workshop “Speech in Cars”
at the occasion of the ITN Oct., 15-17 in Torino.
Collecting all information related to performance assessment performed during
the standardization of an ITU-T Recommendation G.71x or G.72x in a single ITU-T
publication would be useful. The action to produce a Technical paper on G.71x or
G.72x will continue in co-operation with SG16.
Consent was reached on three revised Recommendation:
- P.310 "Transmission characteristics for telephone band (300-3400 Hz)
- P.342 "Transmission characteristics for telephone band (300-3400 Hz) digital loudspeaking and hands-free telephony terminals"
- P.57 "Artificial ears"
- The general revision of Recommendation P.79 is a priority for the study
period, in order to reconsider, in the light of new contributions, the
calculation of Loudness Ratings for devices supporting narrowband, wideband and
super wideband transmission.
- A work item has been created for studying multidimensional testing methodology
in subjective quality assessment.
3.2 Results of the meeting of Working Party 2/12
Consent was reached on one new Recommendation and two revised
- New Recommendation P.834.1, “Extension of the methodology for the
derivation of equipment impairment factors from instrumental models for wideband
- Revised Recommendation G.107, “The E-model, a computational model for use in
- Revised Recommendation P.833.1, “Methodology for the derivation of equipment
impairment factors from subjective listening-only tests for wideband speech codecs”
- Revised Appendix IV to Rec. G.113, “Provisional planning values for the
wideband equipment impairment factor, Ie,wb and the wideband packet loss
robustness factor Bpl,wb” was approved.
- The statistical analysis rules for the P.OLQA competition have been agreed and
training databases exchanged by the proponents. It is planned that the candidate
models will be evaluated prior to the next SG12 meeting.
- The terms of reference for P.NAMS were refined and the next phase of the
collaboration process was started by launching a call for a second round of more
detailed questionnaires. A first draft of terms of reference for P.BNAMS was
also presented for discussion.
VQEG has held two meetings since the last SG12 meeting in May, 2008. VQEG is
currently focusing on objective models for HDTV as well as bit-stream / hybrid
models for MM and TV. SG12 will liaise with VQEG and SG9 to ensure that the
video and multimedia model development in the three different groups is
3.3 Results of the meeting of Working Party 3/12
Consent was reached on one new Recommendation:
- New Recommendation G.1082, “Measurement-based methods for improving the
robustness of IPTV performance”
- New Appendix VII/Y.1540 “Packet Performance Parameters for Optimization of
Stream Repair Techniques” was approved.
- New Appendix VIII/Y.1540 “IP-layer capacity framework” was approved.
- New Appendix V/Y.1542 “Additional considerations for achieving end-to-end
performance objectives for NGN environment” was approved.
- The terms of reference for G.OMVAS (Opinion model for video and audio
streaming applications) were refined and a Call for Proposal was developed. This
document will be issued as a Circular of SG12.
- It was agreed to create a Supplement (provisionally called Suppl. IPQoS),
rather than a Recommendation, based on the draft Recommendation E.841 which had
been studied under SG2 during the last study period.
- New draft Recommendation G.RQAM (Reference guide to QoE assessment
methodologies) was reviewed in collaboration with WPs 1 and 2 (Q.7, Q.8, Q.9,
Q.14, and Q.15). The Recommendation will be created under Q.13 but with close
consultation with these Questions.
Chairman of the QoS Development Group (QSDG) kindly delivered a presentation
about QSDG activities. The next meeting of QSDG will be held in Maputo,
Mozambique, 19-23 October 2009.
Past Executive Summary: