Speech and multimedia Transmission Quality (STQ) - Transmission Requirements for IP-based Narrowband and Wideband Home Gateways and Other Media Gateways from a QoS Perspective as Perceived by the User

The present document provides speech transmission performance requirements for narrowband and wideband media gateways from a QoS perspective as perceived by the user. Media gateways can be network or home based, they may include a transcoding function. The present document covers the following types of IP-based media gateways:
• ATA (Analogue Terminal Adapter), home gateway IP to POTS
• ITA (ISDN Terminal Adapter), home gateway IP to ISDN
• IAD (Integrated Access device), home router including ATA or ITA
• Network based ATA and ITA
• Carrier grade media gateway, network gateway IP to TDM
• IP-to-IP media gateway, network gateway with transcoding and/or other media processing DECT interfaces of media gateways are excluded from the present document and should be measured according to the relevant DECT standards. Interfaces of media gateways used together with terminals as a system (i.e. connected via Ethernet or with a proprietary interface) are excluded in the present document and should be measured according to the relevant terminal standard. If a media gateway includes more than one interface type (e.g. POTS and ISDN), each interface has to be dealt with
differently. The requirements available in the present document will ensure a high compatibility with IP-and TDM-based fixed and wireless terminals and networks, including DECT and mobile terminals. It is the aim to optimize interoperability, the listening and talking quality and the conversational performance. Related requirements and test methods are defined in the present document. The present document does not apply to media gateways with 4-wire analogue interfaces.

Kakovost prenosa govora in večpredstavnih vsebin (STQ) - Prenosne zahteve za ozkopasovne in širokopasovne domače prehode in druge medijske prehode po protokolu IP glede na kakovost storitev (QoS), kot jih dojema uporabnik

Ta dokument podaja zahteve za zmogljivost prenosa govora za ozkopasovne in širokopasovne domače prehode glede na kakovost storitev (QoS), kot jih dojema uporabnik. Medijski prehodi so lahko omrežni ali domači in lahko vsebujejo funkcijo za prekodiranje. Ta dokument obravnava naslednje tipe medijskih prehodov po protokolu IP:
• ATA (analogni telefonski vmesnik), domači prehod IP v POTS
• ITA (ISDN telefonski vmesnik), domači prehod IP v ISDN
• IAD (naprava z integriranim dostopom), domači preusmerjevalnik, vključno z ATA ali ITA
• Omrežni ATA in ITA
• Medijski prehod ponudnika, omrežni prehod IP v TDM
• Medijski prehod IP-v-IP, omrežni prehod s prekodiranjem in/ali drugi medijski vmesniki za obdelavo DECT medijskih prehodov so izključeni iz tega dokumenta in naj bi se jih merilo v skladu z ustreznimi standardi DECT. Vmesniki medijskih prehodov, ki se uporabljajo s terminali kot sistem (tj. povezava prek etherneta ali z lastnim vmesnikom), so izključeni iz tega dokumenta in naj bi se jih merilo v skladu z ustreznim standardom za terminal. Če medijski prehod vključuje več tipov vmesnika (npr. POTS in ISDN), je vsak vmesnik treba obravnavati
drugače. Zahteve, na voljo v tem dokumentu, zagotavljajo visoko združljivost s fiksnimi in brezžičnimi terminali in omrežji po protokolu IP in TDM, vključno z DECT in mobilnimi terminali. Cilj je optimizirati interoperabilnost, kakovost poslušanja in govora ter zmogljivost pogovora. V tem dokumentu so definirane ustrezne zahteve in preskusne metode. Ta dokument ne velja za medijske prehode s 4-žičnimi analognimi vmesniki.

General Information

Status
Published
Publication Date
18-Aug-2014
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
18-Aug-2014
Due Date
23-Oct-2014
Completion Date
19-Aug-2014

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SLOVENSKI STANDARD
SIST ES 202 718 V1.1.1:2014
01-oktober-2014
.DNRYRVWSUHQRVDJRYRUDLQYHþSUHGVWDYQLKYVHELQ 674 3UHQRVQH]DKWHYH]D
R]NRSDVRYQHLQãLURNRSDVRYQHGRPDþHSUHKRGHLQGUXJHPHGLMVNHSUHKRGHSR
SURWRNROX,3JOHGHQDNDNRYRVWVWRULWHY 4R6 NRWMLKGRMHPDXSRUDEQLN

Speech and multimedia Transmission Quality (STQ) - Transmission Requirements for IP-

based Narrowband and Wideband Home Gateways and Other Media Gateways from a
QoS Perspective as Perceived by the User
Ta slovenski standard je istoveten z: ES 202 718 Version 1.1.1
ICS:
33.040.35 Telefonska omrežja Telephone networks
SIST ES 202 718 V1.1.1:2014 en

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
SIST ES 202 718 V1.1.1:2014
---------------------- Page: 2 ----------------------
SIST ES 202 718 V1.1.1:2014
ETSI ES 202 718 V1.1.1 (2011-10)
ETSI Standard
Speech and multimedia Transmission Quality (STQ);
Transmission Requirements for IP-based Narrowband and
Wideband Home Gateways and Other Media Gateways from a
QoS Perspective as Perceived by the User
---------------------- Page: 3 ----------------------
SIST ES 202 718 V1.1.1:2014
2 ETSI ES 202 718 V1.1.1 (2011-10)
Reference
DES/STQ-00145
Keywords
QoS, speech
ETSI
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Copyright Notification
No part may be reproduced except as authorized by written permission.
The copyright and the foregoing restriction extend to reproduction in all media.
© European Telecommunications Standards Institute 2011.
All rights reserved.
TM TM TM

DECT , PLUGTESTS , UMTS and the ETSI logo are Trade Marks of ETSI registered for the benefit of its Members.

3GPP and LTE™ are Trade Marks of ETSI registered for the benefit of its Members and

of the 3GPP Organizational Partners.

GSM® and the GSM logo are Trade Marks registered and owned by the GSM Association.

ETSI
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SIST ES 202 718 V1.1.1:2014
3 ETSI ES 202 718 V1.1.1 (2011-10)
Contents

Intellectual Property Rights ................................................................................................................................ 5

Foreword ............................................................................................................................................................. 5

Introduction ........................................................................................................................................................ 5

1 Scope ........................................................................................................................................................ 6

2 References ................................................................................................................................................ 6

2.1 Normative references ......................................................................................................................................... 6

2.2 Informative references ........................................................................................................................................ 8

3 Definitions and abbreviations ................................................................................................................... 8

3.1 Definitions .......................................................................................................................................................... 8

3.2 Abbreviations ..................................................................................................................................................... 9

4 General considerations ............................................................................................................................. 9

4.1 Default Coding Algorithm .................................................................................................................................. 9

4.2 End-to-end considerations ................................................................................................................................ 10

4.3 Parameters to be investigated ........................................................................................................................... 10

4.3.1 Applicability of parameters to different MGWs ......................................................................................... 10

5 Test equipment ....................................................................................................................................... 11

5.1 IP half channel measurement adaptor ............................................................................................................... 11

5.2 Environmental conditions for tests ................................................................................................................... 12

5.3 Accuracy of measurements and test signal generation ..................................................................................... 12

5.4 Network impairment simulation ....................................................................................................................... 12

6 Requirements and associated Measurement Methodologies .................................................................. 13

6.1 Test setup.......................................................................................................................................................... 13

6.1.1 Setup for Media Gateways with 4-wire interface ....................................................................................... 14

6.1.2 Setup for Media Gateways with 2-wire interface ....................................................................................... 14

6.1.3 Setup for Media Gateways with Wireless Access ....................................................................................... 15

6.1.4 Setup for IP-to-IP Media Gateways ............................................................................................................ 15

6.1.5 Test Signal Levels ....................................................................................................................................... 16

6.1.6 Background noise simulation ...................................................................................................................... 16

6.2 Coding independent parameters ....................................................................................................................... 16

6.2.1 Send Frequency response ............................................................................................................................ 16

6.2.2 Circuit Loudness Rating in Send ................................................................................................................ 17

6.2.3 Linearity Range for CLR (SND) ................................................................................................................. 18

6.2.4 Send Distortion ........................................................................................................................................... 19

6.2.5 Spurious Out-of-Band Signals in Send direction ........................................................................................ 20

6.2.6 Send Noise .................................................................................................................................................. 20

6.2.7 Receive Frequency Response ..................................................................................................................... 20

6.2.8 Circuit Loudness Rating in Receive ........................................................................................................... 21

6.2.9 Linearity Range for CLR (RCV) ................................................................................................................ 22

6.2.10 Receive Distortion ...................................................................................................................................... 23

6.2.11 Out-of-Band Signals Wideband to Narrowband Transcoding .................................................................... 24

6.2.12 Spurious Out-of-band Signals Narrowband to Wideband Transcoding ...................................................... 24

6.2.13 Minimum Activation Level and Sensitivity in Receive Direction .............................................................. 25

6.2.14 Receive Noise ............................................................................................................................................. 25

6.2.15 Double Talk Performance ........................................................................................................................... 26

6.2.15.1 Attenuation Range in Send Direction during Double Talk A ..................................................... 26

H,S,dt

6.2.15.2 Attenuation Range in Receive Direction during Double Talk A ................................................ 28

H,R,dt

6.2.15.3 Detection of Echo Components during Double Talk ............................................................................ 29

6.2.15.4 Minimum Activation Level and Sensitivity of Double Talk Detection ................................................ 31

6.2.16 Switching Characteristics ........................................................................................................................... 31

6.2.16.1 Activation in Send Direction ................................................................................................................. 31

6.2.16.2 Activation in Receive Direction ............................................................................................................ 32

ETSI
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SIST ES 202 718 V1.1.1:2014
4 ETSI ES 202 718 V1.1.1 (2011-10)

6.2.16.3 Silence Suppression and Comfort Noise Generation ............................................................................ 33

6.2.17 Background Noise Performance ................................................................................................................. 33

6.2.17.1 Performance in Send Direction in the Presence of Background Noise ................................................. 33

6.2.17.2 Quality of Speech with Background Noise ........................................................................................... 34

6.2.17.3 Quality of Background Noise Transmission (with Far End Speech) .................................................... 35

6.2.17.4 Quality of Background Noise Transmission (with Near End Speech) .................................................. 36

6.2.18 Quality of Echo Cancellation ...................................................................................................................... 36

6.2.18.1 Echo paths ............................................................................................................................................. 36

6.2.18.2 Echo Performance According to ITU-T Recommendation G.168 ........................................................ 37

6.2.18.3 Terminal Coupling Loss (TCLw) .......................................................................................................... 37

6.2.18.4 Temporal Echo Effects .......................................................................................................................... 38

6.2.18.5 Spectral Echo Attenuation ..................................................................................................................... 38

6.2.18.6 Occurrence of Artefacts ........................................................................................................................ 39

6.2.19 Variant Impairments; Network dependant .................................................................................................. 39

6.2.19.1 Clock Accuracy Send ............................................................................................................................ 39

6.2.19.2 Clock Accuracy Receive ....................................................................................................................... 39

6.2.19.3 Send Delay Variation ............................................................................................................................ 40

6.2.19.4 Delay versus Time Receive ................................................................................................................... 40

6.2.19.5 Quality of Jitter buffer adjustment ........................................................................................................ 40

6.2.20 Immunity to DTMF False Detection in Send Direction .............................................................................. 40

6.3 Codec Specific Requirements........................................................................................................................... 41

6.3.1 Send Delay .................................................................................................................................................. 41

6.3.2 Receive delay .............................................................................................................................................. 42

6.3.3 Delay for IP-to-IP MGW ............................................................................................................................ 44

6.3.4 Objective Listening Speech Quality MOS-LQO in Send direction ............................................................ 44

6.3.5 Objective Listening Quality MOS-LQO in Receive direction .................................................................... 45

6.3.5.1 Efficiency of Packet Loss Concealment (PLC) ..................................................................................... 47

6.3.5.2 Efficiency of Delay Variation Removal ................................................................................................ 47

Annex A (informative): Impulse Response of a Narrowband and Wideband DECT PP ................ 48

Annex B (normative): Test signal for immunity to DTMF false detection in send direction ........ 50

Annex C (informative): Bibliography ................................................................................................... 51

History .............................................................................................................................................................. 52

ETSI
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SIST ES 202 718 V1.1.1:2014
5 ETSI ES 202 718 V1.1.1 (2011-10)
Intellectual Property Rights

IPRs essential or potentially essential to the present document may have been declared to ETSI. The information

pertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found

in ETSI SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in

respect of ETSI standards", which is available from the ETSI Secretariat. Latest updates are available on the ETSI Web

server (http://ipr.etsi.org).

Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI. No guarantee

can be given as to the existence of other IPRs not referenced in ETSI SR 000 314 (or the updates on the ETSI Web

server) which are, or may be, or may become, essential to the present document.
Foreword

This ETSI Standard (ES) has been produced by ETSI Technical Committee Speech and multimedia Transmission

Quality (STQ).
Introduction

Traditionally, the analogue and digital telephones were interfacing switched-circuit 64 kbit/s PCM networks. With the

fast growth of IP networks, packet-switched networks (VoIP) interfacing PSTN networks and mobile networks, as well

as different types of IP-terminals, are being rapidly introduced. Different types of gateways are used to interconnect to

such IP networks. Since the IP networks will be in many cases interworking with the traditional PSTN and private

networks, many of the basic transmission requirements have to be harmonized between these different types of network

from an end-to-end perspective, including specifications for the edge points.

The present document covers IP-based narrowband and wideband home gateways and other media gateways. It aims to

enhance the interoperability and end-to-end quality.

In contrast to other standards which define minimum performance requirements, it is the intention of the present

document to specify gateway equipment requirements which enable manufacturers and service providers to enable

end-to-end speech performance as perceived by the user. These requirements are absolutely necessary to ensure a good

quality, but they are not sufficient. They have to be combined with requirements (and associated relevant measurement

methods) for other elements in the transmission chain (core IP network, PSTN, terminals), as well as for the whole

mouth-to-ear transmission path.
ETSI
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SIST ES 202 718 V1.1.1:2014
6 ETSI ES 202 718 V1.1.1 (2011-10)
1 Scope

The present document provides speech transmission performance requirements for narrowband and wideband media

gateways from a QoS perspective as perceived by the user. Media gateways can be network or home based, they may

include a transcoding function. The present document covers the following types of IP-based media gateways:

• ATA (Analogue Terminal Adapter), home gateway IP to POTS
• ITA (ISDN Terminal Adapter), home gateway IP to ISDN
• IAD (Integrated Access device), home router including ATA or ITA
• Network based ATA and ITA
• Carrier grade media gateway, network gateway IP to TDM

• IP-to-IP media gateway, network gateway with transcoding and/or other media processing

DECT interfaces of media gateways are excluded from the present document and should be measured according to the

relevant DECT standards.

Interfaces of media gateways used together with terminals as a system (i.e. connected via Ethernet or with a proprietary

interface) are excluded in the present document and should be measured according to the relevant terminal standard.

If a media gateway includes more than one interface type (e.g. POTS and ISDN), each interface has to be dealt with

differently.

The requirements available in the present document will ensure a high compatibility with IP-and TDM-based fixed and

wireless terminals and networks, including DECT and mobile terminals.

It is the aim to optimize interoperability, the listening and talking quality and the conversational performance. Related

requirements and test methods are defined in the present document.

The present document does not apply to media gateways with 4-wire analogue interfaces.

2 References

References are either specific (identified by date of publication and/or edition number or version number) or

non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the

reference document (including any amendments) applies.

Referenced documents which are not found to be publicly available in the expected location might be found at

http://docbox.etsi.org/Reference.

NOTE: While any hyperlinks included in this clause were valid at the time of publication, ETSI cannot guarantee

their long term validity.
2.1 Normative references

The following referenced documents are necessary for the application of the present document.

[1] ETSI EN 300 726: "Digital cellular telecommunications system (Phase 2+) (GSM); Enhanced Full

Rate (EFR) speech transcoding (GSM 06.60)".

[2] ETSI TS 126 171: "Digital cellular telecommunications system (Phase 2+); Universal Mobile

Telecommunications System (UMTS); AMR speech codec, wideband; General description

(3GPP TS 26.171 version 6.0.0 Release 6)".

[3] ITU-T Recommendation G.107: "The E-model, a computational model for use in transmission

planning".
ETSI
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SIST ES 202 718 V1.1.1:2014
7 ETSI ES 202 718 V1.1.1 (2011-10)
[4] ITU-T Recommendation G.108: "Application of the E-model: A planning guide".

[5] ITU-T Recommendation G.109: "Definition of categories of speech transmission quality".

[6] ITU-T Recommendation G.100.1: "The use of the decibel and of relative levels in speechband

telecommunications".

[7] ITU-T Recommendation G.111: "Loudness Ratings (LRs) in an international connection".

[8] ITU-T Recommendation G.122: "Influence of national systems on stability and talker echo in

international connections".

[9] ITU-T Recommendation G.711: "Pulse code modulation (PCM) of voice frequencies".

[10] ITU-T Recommendation G.723.1: "Dual rate speech coder for multimedia communications

transmitting at 5.3 and 6.3 kbit/s".

[11] ITU-T Recommendation G.726: "40, 32, 24, 16 kbit/s Adaptive Differential Pulse Code

Modulation (ADPCM)".

[12] ITU-T Recommendation G.729: "Coding of speech at 8 kbit/s using conjugate-structure algebraic-

code-excited linear prediction (CS-ACELP)".

[13] ITU-T Recommendation G.729.1: "G.729-based embedded variable bit-rate coder: An 8-32 kbit/s

scalable wideband coder bitstream interoperable with G.729".

[14] ITU-T Recommendation G.1020: "Performance parameter definitions for quality of speech and

other voiceband applications utilizing IP networks".
[15] ITU-T Recommendation P.50: "Artificial voices".

[16] ITU-T Recommendation P.340: "Transmission characteristics and speech quality parameters of

hands-free terminals".
[17] ITU-T Recommendation P.501: "Test signals for use in telephonometry".

[18] ITU-T Recommendation P.502: "Objective test methods for speech communication systems using

complex test signals".

[19] ITU-T Recommendation P.862: "Perceptual evaluation of speech quality (PESQ): An objective

method for end-to-end speech quality assessment of narrow-band telephone networks and speech

codecs".
[20] ISO 3 (1973): "Preferred numbers - Series of preferred numbers".
[21] ITU-T Recommendation P.800.1: "Mean Opinion Score (MOS) terminology".

[22] ETSI TS 102 971: "Access and Terminals (AT); Public Switched Telephone Network (PSTN);

Harmonized specification of physical and electrical characteristics of a 2-wire analogue interface

for short line interface".

[23] ETSI ES 201 970: "Access and Terminals (AT); Public Switched Telephone Network (PSTN);

Harmonized specification of physical and electrical characteristics at a 2-wire analogue presented

Network Termination Point (NTP)".
[24] ITU-T Recommendation G.168: "Digital network echo cancellers".

[25] ITU-T Recommendation P.863: "Perceptual objective listening quality assessment".

[26] ITU-T Recommendation G.722: "7 kHz audio-coding within 64 kbit/s".

[27] ITU-T Recommendation G.722.1: "Low-complexity coding at 24 and 32 kbit/s for hands-free

operation in systems with low frame loss".

[28] ITU-T Recommendation G.722.2: "Wideband coding of speech at around 16 kbit/s using Adaptive

Multi-Rate Wideband (AMR-WB)".
ETSI
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SIST ES 202 718 V1.1.1:2014
8 ETSI ES 202 718 V1.1.1 (2011-10)

[29] ITU-T Recommendation P.862.1: "Mapping function for transforming P.862 raw result scores to

MOS-LQO".
2.2 Informative references

The following referenced documents are not necessary for the application of the present document but they assist the

user with regard to a particular subject area.

[i.1] ETSI EG 202 396-1: "Speech and multimedia Transmission Quality (STQ); Speech quality

performance in the presence of background noise; Part 1: Background noise simulation technique

and background noise database".

[i.2] ETSI EG 202 425: "Speech Processing, Transmission and Quality Aspects (STQ); Definition and

implementation of VoIP reference point".

[i.3] ETSI EG 202 396-3: "Speech and multimedia Transmission Quality (STQ); Speech Quality

performance in the presence of background noise Part 3: Background noise transmission -

Objective test methods".

[i.4] IETF RFC 2833: "RTP Payload for DTMF Digits, Telephony Tones and Telephony Signals".

[i.5] IETF RFC 4733: "RTP Payload for DTMF Digits, Telephony Tones, and Telephony Signals".

[i.6] ETSI TR 102 927: "Speech and multimedia Transmission Quality (STQ); Packet Loss

Concealment (PLC) performance measurement setup for home networks".
3 Definitions and abbreviations
3.1 Definitions

For the purposes of the present document, the following terms and definitions apply:

0dBr point: reference point always located at the digital side of the gateway, for IP-IP gateways located at the input of

the MGW under test
NOTE: See ITU-T Recommendation G.100.1 [6].

2-wire interface: in the context of the present document, the telephony analogue interface over 2-wires used in the

local loop

4-wire interface: in the context of the present document, a 4-wire digital interface with separate channels for both

directions, irrespective of the physical transmission technology

codec: combination of an analogue-to-digital encoder and a digital-to-analogue decoder operating in opposite directions

of transmission in the same equipment

Composite Source Signal (CSS): signal composed in time by various signal elements

MGW with 2-wire interface: MGW with an analogue 2-wire interface (ATA)

MGW with 4-wire interface: MGW with only 4-wire interfaces, e.g. ITA, IP-to-IP and wireless access points

nominal setting of the volume control: when a receive volume control is provided, the setting which is closest to the

nominal RLR of 2 dB

receive direction: the direction from packet switched interfaces towards a synchronous interface (e.g. ISDN, analogue)

or between two packet switched interfaces (for media gateways with packet switched transport on only one side)

NOTE: For media gateways with packet switched transport on both sides (IP-to-IP-MGW), the requirements of

the receive direction have to be applied in both directions.
ETSI
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SIST ES 202 718 V1.1.1:2014
9 ETSI ES 202 718 V1.1.1 (2011-10)

receive interface: interface in the measurement setup, where a receive signal is injected and/or a send signal is

measured.

send direction: direction from a synchronous interface (e.g. ISDN, analogue) towards a packet switched interface (for

media gateways with packet switched interface on only one side)

NOTE: For media gateways with packet switched interfaces on both sides the requirements of the send direction

are not relevant.

send interface: interface in the measurement setup, where a send signal is injected and/or a receive signal is measured

3.2 Abbreviations
For the purposes of the present document, the following abbreviations apply:
ATA Analogue Terminal Adapter
CLR Circuit Loudness Rating
CSS Composite Source Signal
DSL Digital Subscriber Line
DSLAM Digital Subscriber Line Access Multiplexer
DTMF Dual Tone Multi Frequency
EL Echo Loss
IAD Integrated Access device
IP Internet Protocol
ITA ISDN Terminal Adapter
JLR Junction Loudness Rating
MGW Media GateWay
MOS-LQOy Mean Opinion Score - Listening Quality Objective
NOTE: See ITU-T Recommendation P.800.1 [21].
NLP Non Linear Processor
PCM Pulse Code Modulation
PESQ™ Perceptional Evaluation of Speech Quality™
PLC Packet Loss Concealment
PN Pseudo-random Noise
POI Point Of Interconnect
POTS Plain Old Telephone Service
PSTN Public Switched Telephone Network
QoS Quality of Service
TCL Terminal Coupling Loss
TCN Trace Control for Netem™
TDM Time Division Multiplexing
VAD Voice Activity Detection
VoIP Voice over Internet Protocol
4 General considerations
4.1 Default Coding Algorithm

Narrowband VoIP gateways shall support the coding algorithm according to ITU-T Recommendation G.711 [9] (both

µ-law and A-law). VoIP gateways may support other coding algorithms.

Wideband VoIP gateways shall support the coding algorithm according to ITU-T Recommendation G.722 [26]. VoIP

gateways may support other coding algorithms.

NOTE: Associated Packet Loss Concealment (PLC) e.g. as defined in ITU-T Recommendation G.711 [9]

appendix I should be used.
ETSI
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SIST ES 202 718 V1.1.1:2014
10 ETSI ES 202 718 V1.1.1 (2011-10)
4.2 End-to-end considerations

In order to achieve a desired end-to-end speech transmission performance (mouth-to-ear) it is r

...

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