Speech and multimedia Transmission Quality (STQ) - User related QoS parameter definitions and measurements - Part 2: Voice telephony, Group 3 fax, modem data services and SMS

The present document contains definitions and measurement methods for a range of user perceivable Quality of Service (QoS) parameters. The purpose of these parameters is to define objective and comparable measures of the QoS delivered to users/customers for use by users/customers. The present document applies to any telecommunication service, however, some parameters may have a limited application. The present document is intended to provide a menu from which individual items can be selected. There is no obligation to use any or all of the parameters.
The QoS parameters are related primarily to services and service features and not to the technology used to provide the services. Therefore the parameters should be capable of use when the services are provided on new technologies such as IP and ATM or other packet switched technologies as well as on circuit switched technologies.
The establishment of target values for QoS is beyond the scope of the present document. The QoS parameters listed in the present document are also not intended to assess the complete QoS of a telecommunication service. The present document provides a set of QoS parameters that covers specific user related QoS aspects rather than a complete list of QoS parameters. This set has been chosen to address areas where monitoring of QoS is likely to be most worthwhile, i.e. the areas that are most likely to be affected by any QoS problems. If stakeholders wish to examine other QoS aspects they are recommended to follow the general approach of the present document - as far as practicable - as a basis for the development of definitions and measurement methods for new
specific QoS parameters.
The set of QoS parameters is designed to be understood by the users of various telecommunications services. Sub-sets of these parameters can be selected for use in different circumstances. For example a specific parameter might be relevant for many users in some countries or markets but the same parameter might not be of relevance in others.
Therefore stakeholders - users, customers, regulators, service providers, network operators and other parties interested in the use of QoS parameters - should decide in co-operation, which parameters and which measures should be used in their particular situation. This decision should take account of:
• The precise purpose for which they will be used.
• The general level of quality achieved by most operators/providers.
• The degree to which the parameters will provide a reliable comparison of performance.
• The cost of measuring and reporting each parameter.

Kakovost prenosa govora in večpredstavnih vsebin (STQ) - Definicije in meritve parametrov QoS, ki se nanašajo na uporabnika - 2. del: Govorna telefonija, faksimile skupine 3, podatkovne storitve prek modemov in storitve kratkih sporočil (SMS)

Ta dokument vsebuje definicije in merilne metode za vrsto parametrov kakovosti storitve (QoS), ki jih zazna uporabnik. Namen teh parametrov je opredeliti primernost in primerljiva merila kakovosti storitev za uporabnika/potrošnika, ki jih sam lahko uporablja. Ta dokument velja za vse telekomunikacijske storitve, vendar imajo nekateri parametri lahko omejeno uporabnost. Ta dokument zagotavlja meni, iz katerega se lahko izbirajo posamezni elementi. Uporaba nobenega od parametrov ni obvezna.
Parametri QoS se nanašajo predvsem na storitve in lastnosti storitev in ne na tehnologijo zagotavljanja storitev. Parametri morajo torej biti uporabni pri zagotavljanju storitev z novimi tehnologijami, kot sta IP in ATM ali druge tehnologije paketnega prenosa, in z vodovno komutiranimi tehnologijami.
Vzpostavitev ciljnih vrednost za QoS je zunaj področja uporabe tega dokumenta. Parametri QoS, navedeni v tem dokumentu, prav tako niso predvideni za ocenjevanje popolne QoS telekomunikacijskih storitev. Ta dokument podaja set parametrov QoS, ki zajema posebne vidike QoS, nanašajoče se na uporabnika, in ne celotnega seznama parametrov QoS. Ta set je bil izbran za obravnavo področij, na katerih je spremljanje QoS najkoristnejše, tj. področij, ki jih kakršna koli težava s QoS najverjetneje prizadene. Če zainteresirane strani želijo preučiti druge vidike QoS, naj kot podlago za razvoj definicij in merilnih metod za nove specifične parametre QoS upoštevajo splošni pristop tega dokumenta, kolikor je uporaben.
Set parametrov QoS morajo razumeti uporabniki različnih telekomunikacijskih storitev. Za uporabo v različnih okoliščinah se lahko izberejo podseti teh parametrov. Določen parameter je na primer lahko pomemben za številne uporabnike v nekaterih državah oziroma tržiščih, medtem ko drugje ni pomemben.
Zainteresirane strani – uporabniki, stranke, regulativni organi, izvajalci storitev, upravljavci omrežij in druge stranke z interesom pri uporabi parametrov QoS – naj se torej v sodelovanju odločijo, kateri parametri in merila naj se uporabijo v njihovi situaciji. Pri tej odločitvi je treba upoštevati:
• Natančen namen uporabe.
• Splošno raven kakovosti, ki jo dosega večina upravljavcev/izvajalcev.
• Stopnjo, do katere bodo parametri zagotavljali zanesljivo primerjavo učinkovitosti.
• Strošek merjenja in poročanja o vsakem parametru.

General Information

Status
Published
Publication Date
08-Jun-2011
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
03-May-2011
Due Date
08-Jul-2011
Completion Date
09-Jun-2011

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SLOVENSKI STANDARD
SIST-V ETSI/EG 202 057-2 V1.3.2:2011
01-julij-2011
.DNRYRVWSUHQRVDJRYRUDLQYHþSUHGVWDYQLKYVHELQ 674 'HILQLFLMHLQPHULWYH
SDUDPHWURY4R6NLVHQDQDãDMRQDXSRUDEQLNDGHO*RYRUQDWHOHIRQLMD

IDNVLPLOHVNXSLQHSRGDWNRYQHVWRULWYHSUHNPRGHPRYLQVWRULWYHNUDWNLKVSRURþLO

606
Speech and multimedia Transmission Quality (STQ) - User related QoS parameter
definitions and measurements - Part 2: Voice telephony, Group 3 fax, modem data
services and SMS
Ta slovenski standard je istoveten z: EG 202 057-2
ICS:
33.040.35 Telefonska omrežja Telephone networks
SIST-V ETSI/EG 202 057-2 V1.3.2:2011 en

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

---------------------- Page: 1 ----------------------
SIST-V ETSI/EG 202 057-2 V1.3.2:2011
---------------------- Page: 2 ----------------------
SIST-V ETSI/EG 202 057-2 V1.3.2:2011
ETSI EG 202 057-2 V1.3.2 (2011-04)
ETSI Guide
Speech and multimedia Transmission Quality (STQ);
User related QoS parameter definitions and measurements;
Part 2: Voice telephony, Group 3 fax,
modem data services and SMS
---------------------- Page: 3 ----------------------
SIST-V ETSI/EG 202 057-2 V1.3.2:2011
2 ETSI EG 202 057-2 V1.3.2 (2011-04)
Reference
REG/STQ-00149-2
Keywords
data, fax, modem, QoS, quality, user, voice
ETSI
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Important notice
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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 TM

DECT , PLUGTESTS , UMTS , TIPHON , the TIPHON logo and the ETSI logo are Trade Marks of ETSI registered

for the benefit of its Members.

3GPP is a Trade Mark of ETSI registered for the benefit of its Members and of the 3GPP Organizational Partners.

LTE™ is a Trade Mark of ETSI currently being 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-V ETSI/EG 202 057-2 V1.3.2:2011
3 ETSI EG 202 057-2 V1.3.2 (2011-04)
Contents

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

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

1 Scope ........................................................................................................................................................ 7

2 References ................................................................................................................................................ 7

2.1 Normative references ......................................................................................................................................... 7

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

3 Definitions and abbreviations ................................................................................................................... 9

3.1 Definitions .......................................................................................................................................................... 9

3.2 Abbreviations ................................................................................................................................................... 11

4 General considerations ........................................................................................................................... 12

4.1 Services covered ............................................................................................................................................... 12

4.2 Use of the parameters ....................................................................................................................................... 12

4.3 Reporting for different classes of customers .................................................................................................... 12

4.4 Non standard levels of QoS .............................................................................................................................. 13

4.5 Reporting for directly - and indirectly-serviced customers .............................................................................. 13

4.6 Data processing issues ...................................................................................................................................... 13

4.7 Data collection period ...................................................................................................................................... 13

4.8 Sampling and test calls ..................................................................................................................................... 14

4.9 Comparability of measurements ....................................................................................................................... 14

4.10 Publication of QoS parameters ......................................................................................................................... 14

5 QoS parameters for voice, data and fax services accessed via the PTN and SMS ................................. 14

5.1 Unsuccessful call ratio ...................................................................................................................................... 16

5.1.1 Definition .................................................................................................................................................... 16

5.1.2 Application ................................................................................................................................................. 16

5.1.3 Measurement and statistics ......................................................................................................................... 16

5.1.4 Further considerations................................................................................................................................. 17

5.2 Call set up time ................................................................................................................................................. 18

5.2.1 Definition .................................................................................................................................................... 18

5.2.2 Application ................................................................................................................................................. 18

5.2.3 Measurement and statistics ......................................................................................................................... 18

5.2.4 Further considerations................................................................................................................................. 19

5.3 Speech connection quality ................................................................................................................................ 20

5.3.1 General considerations ................................................................................................................................ 20

5.3.2 Evaluation methods..................................................................................................................................... 21

5.3.2.1 Methods based on intrusive measurements ........................................................................................... 21

5.3.2.2 Methods based on non-intrusive measurements .................................................................................... 22

5.3.2.3 Methods based on the usage of the E model ......................................................................................... 22

5.3.3 Practical Implementation of parametrical model ........................................................................................ 23

5.3.3.1 Results ................................................................................................................................................... 24

5.3.3.2 Further considerations ........................................................................................................................... 24

5.3.4 Application ................................................................................................................................................. 24

5.4 Fax connection quality ..................................................................................................................................... 24

5.4.1 Definition .................................................................................................................................................... 24

5.4.2 Application ................................................................................................................................................. 25

5.4.3 Measurement and statistics ......................................................................................................................... 25

5.5 Data rate of dial-up access to the Internet ........................................................................................................ 25

5.5.1 Definition .................................................................................................................................................... 25

5.5.2 Application ................................................................................................................................................. 26

5.5.3 Measurement and statistics ......................................................................................................................... 26

5.5.4 Further considerations................................................................................................................................. 26

5.6 Short Message Service (SMS) QoS parameters ............................................................................................... 27

5.6.1 Successful SMS Ratio ................................................................................................................................. 27

5.6.1.1 Definition .............................................................................................................................................. 27

ETSI
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SIST-V ETSI/EG 202 057-2 V1.3.2:2011
4 ETSI EG 202 057-2 V1.3.2 (2011-04)

5.6.1.2 Application ............................................................................................................................................ 27

5.6.1.3 Measurement and statistics ................................................................................................................... 27

5.6.1.4 Further considerations ........................................................................................................................... 28

5.6.2 Completion Rate for SMS ........................................................................................................................... 28

5.6.2.1 Definition .............................................................................................................................................. 28

5.6.2.2 Application ............................................................................................................................................ 28

5.6.2.3 Measurement and statistics ................................................................................................................... 28

5.6.3 End-to-End delivery time for SMS ............................................................................................................. 28

5.6.3.1 Definition .............................................................................................................................................. 28

5.6.3.2 Application ............................................................................................................................................ 29

5.6.3.3 Measurement and statistics ................................................................................................................... 29

Annex A: Combination of weekly or monthly results ......................................................................... 30

Annex B: Further explanation of "X % of" ........................................................................................ 31

Annex C: Decision about the success of a call attempt ....................................................................... 32

Annex D: Relationship between the accuracy of the estimator of the unsuccessful call ratio

and the number of calls to be observed ............................................................................... 34

D.1 Theory .................................................................................................................................................... 34

D.2 Guidance ................................................................................................................................................. 36

Annex E: Method of calculating the number of observations required for measures of time ........ 38

Annex F: Standardized test chart for fax connection quality ............................................................ 39

Annex G: Guidance on the selection of representative samples and test calls .................................. 42

G.1 Specific considerations for determining measurement locations and their distribution for voice

quality measurements ............................................................................................................................. 42

Annex H: Application examples of measurement location determination ........................................ 45

H.1 Example for France ................................................................................................................................ 45

H.2 Example for Switzerland ........................................................................................................................ 47

Annex I: Calculation of the Design figure of merit for speech quality ............................................ 49

I.1 The reference terminals .......................................................................................................................... 49

I.2 The network performance characteristics ............................................................................................... 49

I.2.1 Questions for fixed operators ........................................................................................................................... 50

I.2.2 Questions for mobile operators ........................................................................................................................ 52

I.2.3 Treatment of echo ............................................................................................................................................. 56

I.3 Calculating the end-to-end performance ................................................................................................ 56

I.4 Terminals ................................................................................................................................................ 58

Annex J: Bibliography .......................................................................................................................... 59

History .............................................................................................................................................................. 60

ETSI
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SIST-V ETSI/EG 202 057-2 V1.3.2:2011
5 ETSI EG 202 057-2 V1.3.2 (2011-04)
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://webapp.etsi.org/IPR/home.asp).

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 Guide (EG) has been produced by ETSI Technical Committee Speech and multimedia Transmission Quality

(STQ).

The present document is part 2 of a multi-part deliverable covering Speech and multimedia Transmission Quality

(STQ); User related QoS parameter definitions and measurements, as identified below:

Part 1: "General";
Part 2: "Voice telephony, Group 3 fax, modem data services and SMS";
Part 3: "QoS parameters specific to Public Land Mobile Networks (PLMN)";
Part 4: "Internet access".

EG 202 057-1 [i.5] contains general user related QoS parameter definitions and measurement methods that can be

applied to any service.

EG 202 057-2 (the present document) contains user related QoS parameter definitions and measurement methods for

voice, Group 3 fax, modem data services and SMS accessed via the public telecommunication network. The data

parameters are specified for the case where an ITU-T Recommendations V.90 [i.24] and V.92 [i.25], compliant modem

is used since this kind of modem is in common use.

EG 202 057-3 [i.6] contains user related QoS parameter definitions and measurement methods specific to public land

mobile networks (PLMN).

EG 202 057-4 [i.7] contains user related QoS parameter definitions and measurement methods specific to Internet

access.

The present document takes into account as far as practicable the following eight principles:

1) QoS parameters should be easily understood by the public, and be useful and important to them.

2) All parameters are applicable at the network termination point (where appropriate).

3) Where measurements are possible they should be made on the customer's premises, using in-service lines.

NOTE: Literally principles 2 and 3 imply that all measurements should be carried out at the NTP, which would

require co-operation by users and be excessively intrusive, as it would require many visits to the premises

of users. Measurements at the subscriber side of the local exchange (e.g. at the MDF or other possible

connection point/distribution frame in the access network) generally give an adequate representation of

the quality that would be perceived at the NTP for the parameters defined in the present document, and so

this approach is used because it is more practicable and meets the underlying objectives of these

principles.

4) To be as realistic as possible, real traffic rather than test calls should be used as a basis of the measurements,

wherever possible.
ETSI
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SIST-V ETSI/EG 202 057-2 V1.3.2:2011
6 ETSI EG 202 057-2 V1.3.2 (2011-04)

5) Parameters should be capable of verification by independent organizations. This verification might be made by

direct measurements or by audit of service provider's measurements.

6) The accuracy of QoS values should be set to a level consistent with measurement methods being as simple as

possible with costs as low as possible.

7) The parameters are designed for both statistical and individual application. The statistical values should be

derived by the application of a simple statistical function to the individual values. The statistical function

should be specified in this multi-part deliverable. This multi-part deliverable should also contain guidelines on

how statistically significant samples should be selected.

8) The statistical functions should be designed so QoS figures from different service providers can be compared

easily by users and in particular consumers.
ETSI
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SIST-V ETSI/EG 202 057-2 V1.3.2:2011
7 ETSI EG 202 057-2 V1.3.2 (2011-04)
1 Scope

The present document contains definitions and measurement methods for a range of user perceivable Quality of Service

(QoS) parameters. The purpose of these parameters is to define objective and comparable measures of the QoS

delivered to users/customers for use by users/customers. The present document applies to any telecommunication

service, however, some parameters may have a limited application.

The present document is intended to provide a menu from which individual items can be selected. There is no

obligation to use any or all of the parameters.

The QoS parameters are related primarily to services and service features and not to the technology used to provide the

services. Therefore the parameters should be capable of use when the services are provided on new technologies such as

IP and ATM or other packet switched technologies as well as on circuit switched technologies.

The establishment of target values for QoS is beyond the scope of the present document. The QoS parameters listed in

the present document are also not intended to assess the complete QoS of a telecommunication service. The present

document provides a set of QoS parameters that covers specific user related QoS aspects rather than a complete list of

QoS parameters. This set has been chosen to address areas where monitoring of QoS is likely to be most worthwhile,

i.e. the areas that are most likely to be affected by any QoS problems.

If stakeholders wish to examine other QoS aspects they are recommended to follow the general approach of the present

document - as far as practicable - as a basis for the development of definitions and measurement methods for new

specific QoS parameters.

The set of QoS parameters is designed to be understood by the users of various telecommunications services. Sub-sets

of these parameters can be selected for use in different circumstances. For example a specific parameter might be

relevant for many users in some countries or markets but the same parameter might not be of relevance in others.

Therefore stakeholders - users, customers, regulators, service providers, network operators and other parties interested

in the use of QoS parameters - should decide in co-operation, which parameters and which measures should be used in

their particular situation. This decision should take account of:
• The precise purpose for which they will be used.
• The general level of quality achieved by most operators/providers.

• The degree to which the parameters will provide a reliable comparison of performance.

• The cost of measuring and reporting each parameter.
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.

Not applicable.
ETSI
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SIST-V ETSI/EG 202 057-2 V1.3.2:2011
8 ETSI EG 202 057-2 V1.3.2 (2011-04)
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 201 769: "Speech Processing, Transmission and Quality Aspects (STQ); QoS parameter

definitions and measurements; Parameters for voice telephony service required under the ONP

Voice Telephony Directive 98/10/EC".

[i.2] ETSI ETS 300 905: "Digital cellular telecommunications system (Phase 2+) (GSM); Teleservices

supported by a GSM Public Land Mobile Network (PLMN) (GSM 02.03)".

[i.3] ETSI EN 300 659 (all parts) : "Access and Terminals (AT); Analogue access to the Public

Switched Telephone Network (PSTN); Subscriber line protocol over the local loop for display

(and related) services".

[i.4] ETSI EG 201 377-1: "Speech processing, Transmission and Quality aspects (STQ); Specification

and measurement of speech transmission quality; Part 1: Introduction to objective comparison

measurement methods for one-way speech quality across networks".

[i.5] ETSI EG 202 057-1: "Speech Processing, Transmission and Quality Aspects (STQ); User related

QoS parameter definitions and measurements; Part 1: General".

[i.6] ETSI EG 202 057-3: "Speech Processing, Transmission and Quality Aspects (STQ); User related

QoS parameter definitions and measurements; Part 3: QoS parameters specific to Public Land

Mobile Networks (PLMN)".

[i.7] ETSI EG 202 057-4: "Speech Processing, Transmission and Quality Aspects (STQ); User related

QoS parameter definitions and measurements; Part 4: Internet access".

[i.8] ETSI TR 101 949: "Speech Processing, Transmission and Quality Aspects (STQ); QoS parameter

definitions and measurements for use in network-to-network narrowband interconnection".

[i.9] ETSI TS 102 250-6: "Speech Processing, Transmission and Quality Aspects (STQ); QoS aspects

for popular services in GSM and 3G networks; Part 6: Post processing and statistical methods".

[i.10] Directive 98/10/EC of the European Parliament and of the Council of 26 February 1998 on the

application of open network provision (ONP) to voice telephony and on universal service for

telecommunications in a competitive environment.

[i.11] ITU-T Recommendation E.180: "Technical characteristics of tones for the telephone service".

[i.12] ITU-T Recommendation E.425: "Internal automatic observations".
[i.13] ITU-T Recommendation E.451: "Facsimile call cut-off performance".

[i.14] ITU-T Recommendation E.452: "Facsimile modem speed reductions and transaction time".

[i.15] ITU-T Recommendation E.453: "Facsimile image quality as corrupted by transmission-induced

scan line errors".

[i.16] ITU-T Recommendation E.800: "Terms and definitions related to quality of service and network

performance including dependability".

[i.17] ITU-T Recommendation G.107: "The E-model, a computational model for use in transmission

planning".

[i.18] ITU-T Recommendation P.862.1: "Mapping function for transforming P.862 raw result scores to

MOS-LQO".

[i.19] ITU-T Recommendation P.862.2: "Wideband extension to Recommendation P.862 for the

assessment of wideband telephone networks and speech codecs".

[i.20] ITU-T Recommendation G.109: "Definition of categories of speech transmission quality".

ETSI
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SIST-V ETSI/EG 202 057-2 V1.3.2:2011
9 ETSI EG 202 057-2 V1.3.2 (2011-04)

[i.21] ITU-T Recommendation T.4: "Standardization of Group 3 facsimile terminals for document

transmission".

[i.22] ITU-T Recommendation I.210: "Principles of telecommunication services supported by an ISDN

and the means to describe them".

[i.23] ITU-T Recommendation T.22: "Standardized test charts for document facsimile transmissions".

[i.24] ITU-T Recommendation V.90: "A digital modem and analogue modem pair for use on the Public

Switched Telephone Network (PSTN) at data signalling rates of up to 56 000 bit/s downstream

and up to 33 600 bit/s upstream".
[i.25] ITU-T Recommendation V.92: "Enhancements to Recommendation V.90".

[i.26] ITU-T Recommendation Q.850: "Usage of cause and location in the Digital Subscriber Signalling

System No. 1 and the Signalling System No. 7 ISDN User Part".

[i.27] 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".
[i.28] ITU-T Rec
...

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