|
ETSI Guide
Speech Processing, Transmission and Quality Aspects (STQ);
User related QoS parameter definitions and measurements;
Part 2: Voice telephony, Group 3 fax,
modem data services and SMS
---------------------- Page: 1 ----------------------
2 ETSI EG 202 057-2 V1.3.1 (2009-02)
Reference
REG/STQ-00101-2
Keywords
data, fax, modem, QoS, quality, user, voice
ETSI
650 Route des Lucioles
F-06921 Sophia Antipolis Cedex - FRANCE
Tel.: +33 4 92 94 42 00 Fax: +33 4 93 65 47 16
Siret N° 348 623 562 00017 - NAF 742 C
Association à but non lucratif enregistrée à la
Sous-Préfecture de Grasse (06) N° 7803/88
Important notice
Individual copies of the present document can be downloaded from:
http://www.etsi.org
The present document may be made available in more than one electronic version or in print. In any case of existing or
perceived difference in contents between such versions, the reference version is the Portable Document Format (PDF).
In case of dispute, the reference shall be the printing on ETSI printers of the PDF version kept on a specific network drive
within ETSI Secretariat.
Users of the present document should be aware that the document may be subject to revision or change of status.
Information on the current status of this and other ETSI documents is available at
http://portal.etsi.org/tb/status/status.asp
If you find errors in the present document, please send your comment to one of the following services:
http://portal.etsi.org/chaircor/ETSI_support.asp
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 2009.
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.
TM
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
---------------------- Page: 2 ----------------------
3 ETSI EG 202 057-2 V1.3.1 (2009-02)
Contents
Intellectual Property Rights . 5
Foreword . 5
1 Scope . 7
2 References . 7
2.1 Normative references . 8
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 . 13
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 . 17
5.2.1 Definition . 17
5.2.2 Application . 18
5.2.3 Measurement and statistics . 18
5.2.4 Further considerations. 19
5.3 Speech connection quality . 19
5.3.1 General considerations . 19
5.3.2 Evaluation methods. 20
5.3.2.1 Methods based on intrusive measurements . 20
5.3.2.2 Methods based on non-intrusive measurements . 21
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 . 23
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 . 24
5.4.3 Measurement and statistics . 24
5.5 Data rate of dial-up access to the Internet . 25
5.5.1 Definition . 25
5.5.2 Application . 25
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
---------------------- Page: 3 ----------------------
4 ETSI EG 202 057-2 V1.3.1 (2009-02)
5.6.1.2 Application . 27
5.6.1.3 Measurement and statistics . 27
5.6.1.4 Further considerations . 27
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 . 28
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 . 37
Annex F: Standardized test chart for fax connection quality . 38
Annex G: Guidance on the selection of representative samples and test calls . 41
G.1 Specific considerations for determining measurement locations and their distribution for voice
quality measurements . 41
Annex H: Application examples of measurement location determination . 44
H.1 Example for France . 44
H.2 Example for Switzerland . 45
Annex I: Calculation of the Design figure of merit for speech quality . 47
I.1 The reference terminals . 47
I.2 The network performance characteristics . 47
I.2.1 Questions for fixed operators . 48
I.2.2 Questions for mobile operators . 50
I.2.3 Treatment of echo . 54
I.3 Calculating the end-to-end performance . 54
I.4 Terminals . 56
Annex J: Bibliography . 57
History . 58
ETSI
---------------------- Page: 4 ----------------------
5 ETSI EG 202 057-2 V1.3.1 (2009-02)
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 Processing, Transmission and Quality
Aspects (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.21] 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.18] and V.92 [i.19], compliant modem
is used since this kind of modem is in common use.
EG 202 057-3 [i.22] contains user related QoS parameter definitions and measurement methods specific to public land
mobile networks (PLMN).
EG 202 057-4 [i.23] 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
---------------------- Page: 5 ----------------------
6 ETSI EG 202 057-2 V1.3.1 (2009-02)
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
---------------------- Page: 6 ----------------------
7 ETSI EG 202 057-2 V1.3.1 (2009-02)
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 a specific reference, subsequent revisions do not apply.
• Non-specific reference may be made only to a complete document or a part thereof and only in the following
cases:
- if it is accepted that it will be possible to use all future changes of the referenced document for the
purposes of the referring document;
- for informative references.
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.
ETSI
---------------------- Page: 7 ----------------------
8 ETSI EG 202 057-2 V1.3.1 (2009-02)
2.1 Normative references
The following referenced documents are indispensable for the application of the present document. For dated
references, only the edition cited applies. For non-specific references, the latest edition of the referenced document
(including any amendments) applies.
Not applicable.
2.2 Informative references
The following referenced documents are not essential to the use of the present document but they assist the user with
regard to a particular subject area. For non-specific references, the latest version of the referenced document (including
any amendments) applies.
[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] 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.5] ITU-T Recommendation E.180: "Technical characteristics of tones for the telephone service".
[i.6] ITU-T Recommendation E.425: "Internal automatic observations".
[i.7] ITU-T Recommendation E.451: "Facsimile call cut-off performance".
[i.8] ITU-T Recommendation E.452: "Facsimile modem speed reductions and transaction time".
[i.9] ITU-T Recommendation E.453: "Facsimile image quality as corrupted by transmission-induced
scan line errors".
[i.10] ITU-T Recommendation E.800: "Terms and definitions related to quality of service and network
performance including dependability".
[i.11] ITU-T Recommendation G.107: "The E-model, a computational model for use in transmission
planning".
[i.12] ITU-T Recommendation P.862.1: "Mapping function for transforming P.862 raw result scores to
MOS-LQO".
[i.13] ITU-T Recommendation P.862.2: "Wideband extension to Recommendation P.862 for the
assessment of wideband telephone networks and speech codecs".
[i.14] ITU-T Recommendation G.109: "Definition of categories of speech transmission quality".
[i.15] ITU-T Recommendation T.4: "Standardization of Group 3 facsimile terminals for document
transmission".
[i.16] ITU-T Recommendation I.210: "Principles of telecommunication services supported by an ISDN
and the means to describe them".
[i.17] ITU-T Recommendation T.22: "Standardized test charts for document facsimile transmissions".
ETSI
---------------------- Page: 8 ----------------------
9 ETSI EG 202 057-2 V1.3.1 (2009-02)
[i.18] 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.19] ITU-T Recommendation V.92: "Enhancements to Recommendation V.90".
[i.20] 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.21] ETSI EG 202 057-1: "Speech Processing, Transmission and Quality Aspects (STQ); User related
QoS parameter definitions and measurements; Part 1: General".
[i.22] 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.23] ETSI EG 202 057-4: "Speech Processing, Transmission and Quality Aspects (STQ); User related
QoS parameter definitions and measurements; Part 4: Internet access".
[i.24] 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.25] ITU-T Recommendation P.561: "In-service non-intrusive measurement device - Voice service
measurements".
[i.26] ITU-T Recommendation P.562: "Analysis and interpretation of INMD voice-service
measurements".
[i.27] ITU-T Recommendation P.563: "Single-ended method for objective speech quality assessment in
narrow-band telephony applications".
[i.28] 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.29] ITU-T Recommendation G.114: "One-way transmission time".
[i.30] ITU-T Recommendation G.113: "Transmission impairments due to speech processing".
3 Definitions and abbreviations
3.1 Definitions
For the purposes of the present document, the following terms and definitions apply:
access line: connection from the Network Termination Point (NTP) to the entry point to the local switch or remote
concentrator, whichever is the nearer
NOTE: In many cases this is the main distribution frame.
access network operator: organization that provides the access line
NOTE: In many cases the access network operator will be the direct service provider, but if the line is unbundled,
the direct service provider would be a separate organization.
call by call carrier selection: form of carrier selection where the user dials a carrier access code to indicate which
carrier is to route the call
c
...