SIST ES 202 718 V1.3.1:2018
(Main)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
• New Generation DECT Fixed part with IP interface (only parameters not covered by New Generation DECT)
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.
The requirements for MGWs with respect to voiceband data (VBD) are out of scope in the present document. These
requirements are covered in ETSI TS 102 929 [i.5].
Kakovost prenosa govora in večpredstavnih vsebin (STQ) - Prenosne zahteve za ozkopasovne in širokopasovne domače prehode in 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 druge obdelave medijev
• Nova generacija fiksnih delov DECT z vmesnikom IP (le parametri, ki jih ne obsega DECT nove generacije) – vmesniki medijskih prehodov, ki se uporabljajo s terminali kot sistem (tj. povezava prek etherneta ali lastnega vmesnika), so izključeni iz trenutnega dokumenta in naj bi se jih merilo v skladu z ustreznim standardom za terminal.
Če medijski prehod vključuje več kot en vmesnik (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.
Zahteve za prehode MGW ob upoštevanju podatkov govornega pasu (VBD) so zunaj obsega tega dokumenta. Te zahteve so zajete v standardu ETSI TS 102 929 [i.5].
General Information
Standards Content (sample)
SLOVENSKI STANDARD
SIST ES 202 718 V1.3.1:2018
01-maj-2018
.DNRYRVWSUHQRVDJRYRUDLQYHþSUHGVWDYQLKYVHELQ6743UHQRVQH]DKWHYH]D
R]NRSDVRYQHLQãLURNRSDVRYQHGRPDþHSUHKRGHLQPHGLMVNHSUHKRGHSR
SURWRNROX,3JOHGHQDNDNRYRVWVWRULWHY4R6NRWMLKGRMHPDXSRUDEQLN
Speech and multimedia Transmission Quality (STQ) - Transmission Requirements for IP-
based Narrowband and Wideband Home and Network Media Gateways from a QoSPerspective as Perceived by the User
Ta slovenski standard je istoveten z: ETSI ES 202 718 V1.3.1 (2017-09)
ICS:
33.040.35 Telefonska omrežja Telephone networks
SIST ES 202 718 V1.3.1:2018 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST ES 202 718 V1.3.1:2018
ETSI ES 202 718 V1.3.1 (2017-09)
ETSI STANDARD
Speech and multimedia Transmission Quality (STQ);
Transmission Requirements for IP-based Narrowband and
Wideband Home and Network Media Gateways from
a QoS Perspective as Perceived by the User
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SIST ES 202 718 V1.3.1:2018
2 ETSI ES 202 718 V1.3.1 (2017-09)
Reference
RES/STQ-252
Keywords
QoS, speech
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3 ETSI ES 202 718 V1.3.1 (2017-09)
Contents
Intellectual Property Rights ................................................................................................................................ 5
Foreword ............................................................................................................................................................. 5
Modal verbs terminology .................................................................................................................................... 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 ........................................................................................................................... 10
4.1 Default Coding Algorithm ................................................................................................................................ 10
4.2 End-to-end considerations ................................................................................................................................ 10
4.3 Parameters to be investigated ........................................................................................................................... 11
4.3.1 Applicability of parameters to different MGWs ......................................................................................... 11
5 Test equipment ....................................................................................................................................... 12
5.1 IP half channel measurement adaptor ............................................................................................................... 12
5.2 Environmental conditions for tests ................................................................................................................... 12
5.3 Accuracy of measurements and test signal generation ..................................................................................... 13
5.4 Network impairment simulation ....................................................................................................................... 13
6 Requirements and associated Measurement Methodologies .................................................................. 14
6.0 General ............................................................................................................................................................. 14
6.1 Test setup.......................................................................................................................................................... 14
6.1.0 General ........................................................................................................................................................ 14
6.1.1 Setup for Media Gateways with 4-wire interface ....................................................................................... 15
6.1.2 Setup for Media Gateways with 2-wire interface ....................................................................................... 15
6.1.3 Setup for Media Gateways with Wireless Access ....................................................................................... 16
6.1.4 Setup for IP-to-IP Media Gateways ............................................................................................................ 17
6.1.5 Test Signal Levels ....................................................................................................................................... 17
6.1.6 Background noise simulation ...................................................................................................................... 17
6.1.7 Echo paths ................................................................................................................................................... 18
6.2 Coding independent parameters ....................................................................................................................... 19
6.2.1 Send Frequency response ............................................................................................................................ 19
6.2.2 Circuit Loudness Rating in Send ................................................................................................................ 20
6.2.3 Linearity Range for CLR (SND) ................................................................................................................. 20
6.2.4 Send Distortion ........................................................................................................................................... 22
6.2.5 Spurious Out-of-Band Signals in Send direction ........................................................................................ 22
6.2.6 Send Noise .................................................................................................................................................. 23
6.2.7 Receive Frequency Response ..................................................................................................................... 23
6.2.8 Circuit Loudness Rating in Receive ........................................................................................................... 24
6.2.9 Linearity Range for CLR (RCV) ................................................................................................................ 25
6.2.10 Receive Distortion ...................................................................................................................................... 26
6.2.11 Out-of-Band Signals Wideband to Narrowband Transcoding .................................................................... 27
6.2.12 Spurious Out-of-band Signals Narrowband to Wideband Transcoding ...................................................... 27
6.2.13 Minimum Activation Level and Sensitivity in Receive Direction .............................................................. 28
6.2.14 Receive Noise ............................................................................................................................................. 28
6.2.15 Double Talk Performance ........................................................................................................................... 29
6.2.15.0 General .................................................................................................................................................. 29
6.2.15.1 Attenuation Range in Send Direction during Double Talk A ......................................................... 29
H,S,dt6.2.15.2 Attenuation Range in Receive Direction during Double Talk A .................................................... 30
H,R,dt6.2.15.3 Detection of Echo Components during Double Talk ............................................................................ 31
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6.2.15.4 Minimum Activation Level and Sensitivity of Double Talk Detection ................................................ 33
6.2.16 Switching Characteristics ........................................................................................................................... 33
6.2.16.0 General .................................................................................................................................................. 33
6.2.16.1 Activation in Send Direction ................................................................................................................. 34
6.2.16.2 Activation in Receive Direction ............................................................................................................ 34
6.2.16.3 Silence Suppression and Comfort Noise Generation ............................................................................ 35
6.2.17 Background Noise Performance ................................................................................................................. 35
6.2.17.0 General .................................................................................................................................................. 35
6.2.17.1 Performance in Send Direction in the Presence of Background Noise ................................................. 35
6.2.17.2 Quality of Speech with Background Noise ........................................................................................... 36
6.2.17.3 Quality of Background Noise Transmission (with Far End Speech) .................................................... 37
6.2.17.4 Quality of Background Noise Transmission (with Near End Speech) .................................................. 38
6.2.18 Quality of Echo Cancellation ...................................................................................................................... 38
6.2.18.0 General .................................................................................................................................................. 38
6.2.18.1 Echo Performance According to Recommendation ITU-T G.168 ........................................................ 38
6.2.18.2 Terminal Coupling Loss (TCLw, NB) .................................................................................................. 39
6.2.18.3 Terminal Coupling Loss (TCL, WB) .................................................................................................... 39
6.2.18.4 Temporal Echo Effects .......................................................................................................................... 40
6.2.18.5 Spectral Echo Attenuation ..................................................................................................................... 41
6.2.18.6 Occurrence of Artefacts ........................................................................................................................ 41
6.2.18.7 Variable Echo Paths .............................................................................................................................. 41
6.2.19 Variant Impairments; Network dependant .................................................................................................. 42
6.2.19.1 Clock Accuracy Send ............................................................................................................................ 42
6.2.19.2 Clock Accuracy Receive ....................................................................................................................... 42
6.2.19.3 Send Packet Delay Variation................................................................................................................. 42
6.2.20 Immunity to DTMF False Detection in Send Direction .............................................................................. 43
6.2.21 Send and receive delay - round trip delay ................................................................................................... 43
6.3 Codec Specific Requirements........................................................................................................................... 44
6.3.1 Objective Listening Speech Quality MOS-LQO in Send direction ............................................................ 44
6.3.2 Objective Listening Quality MOS-LQO in Receive direction .................................................................... 45
6.3.3 Quality of Jitter buffer adjustment .............................................................................................................. 48
Annex A (informative): Impulse Response of a Narrowband and Wideband DECT PP ................ 50
Annex B (normative): Test signal for immunity to DTMF false detection in send direction ........ 52
Annex C (informative): Example IP Delay variation .......................................................................... 53
Annex D (informative): Bibliography ................................................................................................... 54
History .............................................................................................................................................................. 55
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Intellectual Property Rights
Essential patents
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 (https://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.Trademarks
The present document may include trademarks and/or tradenames which are asserted and/or registered by their owners.
ETSI claims no ownership of these except for any which are indicated as being the property of ETSI, and conveys no
right to use or reproduce any trademark and/or tradename. Mention of those trademarks in the present document does
not constitute an endorsement by ETSI of products, services or organizations associated with those trademarks.
ForewordThis ETSI Standard (ES) has been produced by ETSI Technical Committee Speech and multimedia Transmission
Quality (STQ).Modal verbs terminology
In the present document "shall", "shall not", "should", "should not", "may", "need not", "will", "will not", "can" and
"cannot" are to be interpreted as described in clause 3.2 of the ETSI Drafting Rules (Verbal forms for the expression of
provisions)."must" and "must not" are NOT allowed in ETSI deliverables except when used in direct citation.
IntroductionTraditionally, 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 and network 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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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
• New Generation DECT Fixed part with IP interface (only parameters not covered by New Generation DECT)
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.
The requirements for MGWs with respect to voiceband data (VBD) are out of scope in the present document. These
requirements are covered in ETSI TS 102 929 [i.5].2 References
2.1 Normative 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
referenced document (including any amendments) applies.Referenced documents which are not found to be publicly available in the expected location might be found at
https://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.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 (V6.0.0): "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)".ETSI
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[3] Recommendation ITU-T G.107: "The E-model, a computational model for use in transmission
planning".[4] Recommendation ITU-T G.108, including amendments 1 and 2: "Application of the E-model:
A planning guide".[5] Recommendation ITU-T G.109: "Definition of categories of speech transmission quality".
[6] Recommendation ITU-T G.100.1: "The use of the decibel and of relative levels in speechband
telecommunications".[7] Recommendation ITU-T G.111: "Loudness Ratings (LRs) in an international connection".
[8] Recommendation ITU-T G.122: "Influence of national systems on stability and talker echo in
international connections".[9] Recommendation ITU-T G.711: "Pulse code modulation (PCM) of voice frequencies".
[10] Recommendation ITU-T G.723.1: "Dual rate speech coder for multimedia communications
transmitting at 5.3 and 6.3 kbit/s".[11] Recommendation ITU-T G.726: "40, 32, 24, 16 kbit/s Adaptive Differential Pulse Code
Modulation (ADPCM)".[12] Recommendation ITU-T G.729: "Coding of speech at 8 kbit/s using conjugate-structure algebraic-
code-excited linear prediction (CS-ACELP)".[13] Recommendation ITU-T 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] Void.
[15] Recommendation ITU-T P.863.1: "Application guide for Recommendation ITU-T P.863".
[16] Recommendation ITU-T P.340: "Transmission characteristics and speech quality parameters of
hands-free terminals".[17] Recommendation ITU-T P.501: "Test signals for use in telephonometry".
[18] Recommendation ITU-T P.502: "Objective test methods for speech communication systems using
complex test signals".[19] Recommendation ITU-T P.56: "Objective measurement of active speech level".
[20] IEC 61260-1: "Electroacoustics - Octave-band and fractional-octave-band filters. -
Part 1: Specification".[21] Recommendation ITU-T 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] Recommendation ITU-T G.168: "Digital network echo cancellers".
[25] Recommendation ITU-T P.863: "Perceptual objective listening quality assessment".
[26] Recommendation ITU-T G.722: "7 kHz audio-coding within 64 kbit/s".[27] Recommendation ITU-T G.722.1: "Low-complexity coding at 24 and 32 kbit/s for hands-free
operation in systems with low frame loss".ETSI
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[28] Recommendation ITU-T G.722.2: "Wideband coding of speech at around 16 kbit/s using Adaptive
Multi-Rate Wideband (AMR-WB)".[29] Recommendation ITU-T P.1010: "Fundamental voice transmission objectives for VoIP terminals
and gateways".[30] IETF RFC 3550: "RTP: A Transport Protocol for Real-Time Applications".
[31] 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".2.2 Informative 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
referenced document (including any amendments) applies.NOTE: While any hyperlinks included in this clause were valid at the time of publication, ETSI cannot guarantee
their long term validity.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 202 425: "Speech Processing, Transmission and Quality Aspects (STQ); Definition and
implementation of VoIP reference point".[i.2] IETF RFC 2833: "RTP Payload for DTMF Digits, Telephony Tones and Telephony Signals".
[i.3] IETF RFC 4733: "RTP Payload for DTMF Digits, Telephony Tones, and Telephony Signals".
[i.4] Void.[i.5] ETSI TS 102 929: "Speech and multimedia Transmission Quality (STQ); Procedures for the
identification and selection of common modes of de-jitter buffers and echo cancellers".
[i.6] ETSI TS 103 224: "Speech and multimedia Transmission Quality (STQ); A sound field
reproduction method for terminal testing including a background noise database".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 testNOTE: See Recommendation ITU-T G.100.1 [6].
2-wire interface: in the context of the present document, telephony analogue interface over 2-wires used in the local
loop4-wire interface: in the context of the present document, 4-wire digital interface with separate channels for both
directions, irrespective of the physical transmission technologycodec: combination of an analogue-to-digital encoder and a digital-to-analogue decoder operating in opposite directions
of transmission in the same equipmentComposite Source Signal (CSS): signal composed in time by various signal elements
MGW with 2-wire interface: MGW with an analogue 2-wire interface (ATA)ETSI
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MGW with 4-wire interface: MGW with only 4-wire interfaces
EXAMPLE: ITA, IP-to-IP and wireless access points.
receive direction: 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 t...
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