Quality for Voice & VideoCommunication over IP

QoS in DigitalMobile Networks

DistributedSpeech Recognition

Fixed - MobileConvergence

User relatedQoS Parameters

E-ModelTransmission Planning

Quality ofBackground NoiseTransmission

Speech Quality Test Events

End-to-end communication quality as perceivedby the user has always been of major concern toETSI and its Technical Committee STQ (Speechprocessing, Transmission and Quality aspects).Recent developments in telecommunications,such as the introduction of VoIP and UMTS increa-singly promote the introduction of new services,including wideband speech communication andmultimedia. Simultaneously, the global telecommu-nication landscape is undergoing essential changes,such as the migration from traditional public network operators to NGN service providers.

Liberalization and competition, network inter-connection, the impending change to IP technology,real-time multimedia applications and services,have brought major changes over the last fewyears to the way quality for telecommunications isperceived by the user. The need for a frameworkto test, measure performance, and achieve MediaQuality and Quality of Service (QoS) that takes

into account these changes has become evenmore necessary.

In a multi-vendor environment standards are theonly means to achieve reasonable end-to-endmultimedia quality. STQ represents ETSI's commit-ment to end-to-end multimedia quality for NGN.

End-to-end multimedia quality is a promotio-nal factor for the market.

There will be a huge demand for wideband speechcommunication and multimedia in hands-free,mobile, nomadic and video phone applications inthe near future. Devices designed for such appli-cations will have to rely on non-linear and timevariant signal processing in terminals and networkelements in order to be capable of providing speechquality that satisfies users' demands. Therefore, it is essential to standardize state-of-the-art requirements and test methodologies.

The objective of TC STQ is to ensure the co-ordination, production and maintenance of end-to-end quality related standards, for the timelyand economic development of equipment for usewith existing and future fixed/mobile networktelecommunications service offerings. The mainworking areas of STQ are: Voice and Multimediaover IP (VoIP, MMoIP); excessive acoustic pressureand relevant measurement methods; widebandspeech, including terminals, modelling and assess-ment; and user-oriented QoS.

Within ETSI, STQ is a center of excellencefor end-to-end single media and multimediatransmission performance, QoS parameters fornetworks and services and distributed speechrecognition, and takes responsibility for relatedstandardization of terminals and networks.

STQ has a charter stretching across ALL technologyplatforms and thus works in close co-operation

with all ETSI and 3GPP groups involved in communication aspects; this charter also reachesout to other relevant organizations, such as ITU-T,TIA and IEEE. The STQ Aurora working groupmaintains a set of standards for distributed speechrecognition.

STQ Mobile, the working group on mobile servicesis creating standards on QoS aspects for popularservices in GSM™ and Third Generation networksincluding picture and video quality; new workingareas include aspects of Push-to-Talk over Cellular,videotelephony, mobile broadcast, video qualityfor mobile and picture compression algorithmsand the definition of a reference web page inmobile QoS.

The work area of STQ covers dedicated taskswhich are of relevance to the European regulatoryframework for electronic communications networksand services.

MOTIVATION

THE CHARTER OF STQ

End-to-end communication quality as perceivedby the user has always been of major concern toETSI and its Technical Committee STQ (Speechprocessing, Transmission and Quality aspects).Recent developments in telecommunications,such as the introduction of VoIP and UMTS increa-singly promote the introduction of new services,including wideband speech communication andmultimedia. Simultaneously, the global telecommu-nication landscape is undergoing essential changes,such as the migration from traditional public network operators to NGN service providers.

Liberalization and competition, network inter-connection, the impending change to IP technology,real-time multimedia applications and services,have brought major changes over the last fewyears to the way quality for telecommunications isperceived by the user. The need for a frameworkto test, measure performance, and achieve MediaQuality and Quality of Service (QoS) that takes

into account these changes has become evenmore necessary.

In a multi-vendor environment standards are theonly means to achieve reasonable end-to-endmultimedia quality. STQ represents ETSI's commit-ment to end-to-end multimedia quality for NGN.

End-to-end multimedia quality is a promotio-nal factor for the market.

There will be a huge demand for wideband speechcommunication and multimedia in hands-free,mobile, nomadic and video phone applications inthe near future. Devices designed for such appli-cations will have to rely on non-linear and timevariant signal processing in terminals and networkelements in order to be capable of providing speechquality that satisfies users' demands. Therefore, it is essential to standardize state-of-the-art requirements and test methodologies.

Among its main accomplishments the Committeesees the six-part standard on QoS aspects forpopular services in GSM™ and Third Generationnetworks, and the complete set of ETSI Guides onuser-related QoS parameters, definitions, limitsand measurement methods.

Work was completed on an ETSI Guide on excessiveacoustic pressure, defining test methodologies for

use under the European Commission (EC)Directive on the health and safety requirementsfor the exposure of workers to the risks arisingfrom physical agents (noise).

STQ completed its comprehensive report on thequality aspects of IP based communication, coveringrecent developments designed to handle impair-ments in IP-based networks.

STQ has completed its significant work concerningbackground noise testing methodologies andmeasurement. This work is aimed at improvingthe quality of wideband speech applications bydeveloping a standardized performance testingand evaluation methodology for thetransmission of background noise.

This work is essential for the high quality wide-band communications needed by many of theapplications that the European Commission is promoting such as e-Health and e-Learning.

The objective of TC STQ is to ensure the co-ordination, production and maintenance of end-to-end quality related standards, for the timelyand economic development of equipment for usewith existing and future fixed/mobile networktelecommunications service offerings. The mainworking areas of STQ are: Voice and Multimediaover IP (VoIP, MMoIP); excessive acoustic pressureand relevant measurement methods; widebandspeech, including terminals, modelling and assess-ment; and user-oriented QoS.

Within ETSI, STQ is a center of excellencefor end-to-end single media and multimediatransmission performance, QoS parameters fornetworks and services and distributed speechrecognition, and takes responsibility for relatedstandardization of terminals and networks.

STQ has a charter stretching across ALL technologyplatforms and thus works in close co-operation

with all ETSI and 3GPP groups involved in communication aspects; this charter also reachesout to other relevant organizations, such as ITU-T,TIA and IEEE. The STQ Aurora working groupmaintains a set of standards for distributed speechrecognition.

STQ Mobile, the working group on mobile servicesis creating standards on QoS aspects for popularservices in GSM™ and Third Generation networksincluding picture and video quality; new workingareas include aspects of Push-to-Talk over Cellular,videotelephony, mobile broadcast, video qualityfor mobile and picture compression algorithmsand the definition of a reference web page inmobile QoS.

The work area of STQ covers dedicated taskswhich are of relevance to the European regulatoryframework for electronic communications networksand services.

Network Factors

Networkpacket Loss

NetworkVariable Delay

NetworkFixed Delay

End-to-EndPacket Loss

Codec

End-to-EndDelay

Clock

Jitterbuffer

TerminalFactors Echo path

& control

Congestion

Topology

PerceivedQuality

Distortion

Echo

Delay

Playback Subwoofer

Analyser(2-Channels)

Reference Channel

2 m

2 m

2 m

2 m

MOTIVATION

THE CHARTER OF STQ

RECENT ACHIEVEMENTS

Quality for Voice & VideoCommunication over IP

QoS in DigitalMobile Networks

DistributedSpeech Recognition

Fixed - MobileConvergence

User relatedQoS Parameters

E-ModelTransmission Planning

Quality ofBackground NoiseTransmission

Speech Quality Test Events

The range of work in STQ is expanding. As commu-nications evolve to accommodate other media thansimply voice, new work has been initiated to coverthe quality of data and video transmission & communication. Upcoming Fixed-Mobile Conver-gence (FMC) holds for new challenges for end-to-end media quality, as perceived by the user, whichare consequently addressed by STQ.

Work on QoS for terminals will encompassDECT™, WiFi, home networks and especiallywideband technology.Average measurements of speech quality over a period of time can disguise poor quality at specifictimes – often at peak usage times. New interests forthe future will include defining speech quality percall, which is expected to lead to the improvementin the quality of individual calls.

> Participate in the creation & improvement of standards for end-to-end media quality.

> Share your own knowledge on media quality and make STQ even better.

> Listen to the discussions during regular STQ sessions and special workshops & becomepart of the excellence.

For immediate contact: info@etsi-stq.org

ABOUT ETSIFounded in 1988 to help develop an integrated communications infrastructure in the newly formedEuropean Market, ETSI is one of the three European Standards Organizations and is recognized by theEuropean Union and the European Free Trade Association (EFTA) as the region’s competent body forstandardization in telecommunications and other electronic communications networks and relatedservices.

The Institute was established as a European body and retains European responsibilities. But ETSI has global membership; many of its Members are global players – over 100 of ETSI’s Members (nearly 20%of the total membership) have no established operations in Europe.

ETSI is an independent, non-profit making organization, one of the largest international technical associations in the field of ICT, including telecommunications and broadcasting. Based inSophia Antipolis in the south of France, ETSI currently numbers over 650 Members from 62 countriesaround the world – including manufacturers, network operators, administrations, service providers,research bodies and users – an impressive array of international expertise, all working together towardsthe ultimate goal of a universal information infrastructure.

Wor ld C lass S tandards

www.etsi.org

OUTLOOK

3 EXCELLENT REASONS FOR JOINING STQ