ETSI TS 102 250-3 V1.4.1 (2008-12)

Speech and multimedia Transmission Quality (STQ); QoS aspects for popular services in GSM and 3G networks; Part 3: Typical procedures for Quality of Service measurement equipment

RTS/STQ-00123m

General Information

• Status: Published
• Publication Date: 16-Dec-2008
• Technical Committee: STQ MOBILE - STQ Mobile
• Current Stage: 12 - Completion
• Due Date: 04-Dec-2008
• Completion Date: 17-Dec-2008

Standards Content (Sample)

Technical Specification
Speech and multimedia Transmission Quality (STQ);
QoS aspects for popular services in GSM and 3G networks;
Part 3: Typical procedures for Quality of Service
measurement equipment
2 ETSI TS 102 250-3 V1.4.1 (2008-12)

Reference
RTS/STQ-00123m
Keywords
3G, GSM, network, QoS, service, speech
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ETSI
3 ETSI TS 102 250-3 V1.4.1 (2008-12)
Contents
Intellectual Property Rights.6
Foreword.6
Introduction .7
1 Scope.8
2 References.8
2.1 Normative references.8
2.2 Informative references.8
3 Definitions and abbreviations.9
3.1 Definitions.9
3.2 Abbreviations.9
4 Goal of measurement.10
5 Classification of services.10
5.1 Classification guidelines.10
5.2 General structure of service descriptions.11
6 General aspects for all types of services.11
6.1 Set-up and control .11
6.2 Phase and result classification.11
6.2.1 Phase and result classification for direct services .12
6.2.2 Phase and result classification for store-and-forward services .13
7 Telephony measurements.13
7.1 General aspects.13
7.1.1 Transaction definition and transaction types.13
7.1.2 Parameter overview.14
7.1.2.1 Additional considerations.14
7.1.3 Additional transaction result definitions .14
7.1.4 Content quality.15
7.1.5 Verification of usable two-way connection .15
7.2 Speech telephony.15
7.2.1 Transaction definition and transaction types for speech telephony .15
7.2.2 Parameter overview for speech telephony .16
7.2.3 Additional transaction results for speech telephony .16
7.2.4 Content quality for speech telephony.16
7.2.5 Verification of usable two-way connection for speech telephony .16
7.2.6 Void.16
7.2.7 Transaction definition and transaction types for video telephony .16
7.2.8 Parameter overview for video telephony .16
7.2.9 Additional transaction result definitions for video telephony.17
7.2.10 Content quality for video telephony .17
7.2.11 Verification of usable two-way connection for video telephony .17
8 Store-and-forward services measurement .17
8.1 General aspects.17
8.1.1 Transaction phase and parameter overview .18
8.1.2 Additional transaction result definitions .18
8.1.3 Content quality for Store-and-Forward Services .18
8.1.3.1 SMS.18
8.1.3.2 MMS.18
8.1.3.3 e-Mail.19
8.2 SMS measurements .19
8.2.1 General aspects of SMS measurements .19
8.2.2 Transaction definitions and transaction types for SMS .19
8.2.3 Testing mode for SMS-MT.20
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4 ETSI TS 102 250-3 V1.4.1 (2008-12)
8.2.4 Testing mode for SMS-MO .20
8.2.5 Transaction phase and parameter overview for SMS.20
8.2.6 Possible transaction results for SMS.20
8.2.7 Content quality for SMS .21
8.3 MMS.21
8.3.1 General aspects of MMS measurements.21
8.3.2 Transaction definitions and transaction types for MMS .21
8.3.3 Transaction phase and parameter overview for MMS .22
8.3.4 Additional transaction result definitions for MMS .22
8.3.5 Content quality for MMS.22
8.4 E-Mail.23
8.4.1 Transaction definitions and transaction types for E-Mail .23
8.4.1.1 Standardized E-Mail Content.23
8.4.2 Transaction scenarios.23
8.4.2.1 End-to-End scenario.23
8.4.2.2 Download scenario.24
8.4.3 Protocols.24
8.4.4 Push function.25
8.4.5 Support for header download.25
8.4.6 Timeout.25
8.4.7 Further mandatory requirements.25
8.4.7.1 Guard times.26
8.4.8 Further optional requirements.26
8.4.9 Test sequence for End-to-End scenario .26
8.4.10 Test sequence for Download scenario .30
9 Data measurements.33
9.1 Common aspects.33
9.1.1 Transaction definition and transaction types for data measurements.33
9.1.2 Server types.33
9.1.3 Test data content .34
9.1.4 Transaction phase and parameter overview .34
9.1.4.1 General.34
9.1.4.2 Packet-switched access.35
9.1.4.3 Circuit-switched access.35
9.1.5 Possible transaction results .35
9.1.6 Content quality.36
9.2 FTP.36
9.2.1 Transaction definition and transaction types for FTP.36
9.2.2 Transaction phase and parameter overview for FTP.36
9.2.3 Possible transaction results for FTP.36
9.2.4 Content quality for FTP .36
9.2.5 Content integrity for FTP.36
9.3 HTTP.36
9.3.1 Transaction definition and transaction types for HTTP.36
9.3.2 Transaction phase and parameter overview for HTTP.36
9.3.3 Possible transaction results for HTTP.37
9.3.4 Content quality for HTTP .37
9.3.5 Content integrity for HTTP.37
9.4 E-mail.37
9.4.1 Transaction definition and transaction types for E-mail .37
9.4.2 Transaction phase and parameter overview for E-mail.37
9.4.3 Possible transaction results for E-mail.37
9.4.4 Content quality for E-mail .37
9.4.5 Content integrity for E-mail.37
9.5 WAP.38
9.5.1 Transaction definition and transaction types for WAP .38
9.5.2 Transaction phase and parameter overview for WAP.38
9.5.3 Possible transaction results for WAP.39
9.5.4 Content quality for WAP .39
9.5.5 Content integrity for WAP.39
9.6 Streaming Video.40
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5 ETSI TS 102 250-3 V1.4.1 (2008-12)
9.6.1 Transaction definition and transaction types for streaming video .40
9.6.2 Transaction phase and parameter overview for streaming video.40
9.6.3 Possible transaction results for Streaming Video.40
9.6.4 Content quality for Streaming Video.40
9.6.5 Content integrity for Streaming video .40
History .41

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6 ETSI TS 102 250-3 V1.4.1 (2008-12)
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 Technical Specification (TS) has been produced by ETSI Technical Committee Speech and multimedia
Transmission Quality (STQ).
NOTE: Version 2.1.1 of the present document was published with a wrong version number. Please note that the
present version 1.4.1 has been re-published to correct this and therefore superceeds the previous versions
V1.1.1, V1.2.1 and 2.1.1 which have been withdrawn to avoid confusion.
The present document is part 3 of a multi-part deliverable covering the QoS aspects for popular services in GSM and
3G networks, as identified below:
Part 1: "Identification of Quality of Service aspects";
Part 2: "Definition of Quality of Service parameters and their computation";
Part 3: "Typical procedures for Quality of Service measurement equipment";
Part 4: "Requirements for Quality of Service measurement equipment";
Part 5: "Definition of typical measurement profiles";
Part 6: "Post processing and statistical methods";
Part 7: "Network Based Quality of Service Measurements".
Part 1 identifies QoS aspects for popular services in GSM and 3G networks. For each service chosen QoS indicators are
listed. They are considered to be suitable for the quantitatively characterization of the dominant technical QoS aspects
as experienced from the end-customer perspective.
Part 2 defines QoS parameters and their computation for popular services in GSM and 3G networks. The technical QoS
indicators, listed in part 1, are the basis for the parameter set chosen. The parameter definition is split into two parts: the
abstract definition and the generic description of the measurement method with the respective trigger points. Only
measurement methods not dependent on any infrastructure provided are described in the present document. The
harmonized definitions given in the present document are considered as the prerequisites for comparison of QoS
measurements and measurement results.
Part 3 describes typical procedures used for QoS measurements over GSM, along with settings and parameters for such
measurements.
Part 4 defines the minimum requirements of QoS measurement equipment for GSM and 3G networks in the way that
the values and trigger-points needed to compute the QoS parameter as defined in part 2 can be measured following the
procedures defined in part 3. Test-equipment fulfilling the specified minimum requirements, will allow to perform the
proposed measurements in a reliable and reproducible way.
Part 5 specifies test profiles which are required to enable benchmarking of different GSM or 3G networks both within
and outside national boundaries. It is necessary to have these profiles so that when a specific set of tests are carried out
then customers are comparing "like for like" performance.
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7 ETSI TS 102 250-3 V1.4.1 (2008-12)
Part 6 describes procedures to be used for statistical calculations in the field of QoS measurement of GSM and 3G
networks using probing systems.
Part 7 describes the methodology to be used to get statistical samples that could be representative of the population of
all existent calls so the statistical inferences made from the data collected by test calls are statistically correct and the
error margin could be calculated.
Introduction
All the defined quality of service parameters and their computations are based on field measurements. That indicates
that the measurements were made from customers point of view (full End-to-end perspective, taking into account the
needs of testing).
It is assumed that the end customer can handle his mobile and the services he wants to use (operability is not evaluated
at this time). For the purpose of measurement it is assumed that:
• the service is available and not barred for any reason;
• routing is defined correctly without errors;
• the target subscriber equipment is ready to answer the call;
• voice quality values measured should only be employed by calls ended successfully for statistical analysis;
• need to define similar for video calls;
• however, measured values from calls ended unsuccessfully (e.g. dropped) should be available for additional
evaluations and therefore, must be stored;
• further preconditions may apply when reasonable.
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8 ETSI TS 102 250-3 V1.4.1 (2008-12)
1 Scope
The present document describes typical procedures used for QoS measurements on mobile communication networks,
e.g. GSM or UMTS, along with settings and parameters for such measurements.
Where possible existing ITU-T or ETSI definition are referenced. In some cases ITU-T or ETSI definitions do not exist
or are considered as too generic, then a more service and mobile network specific definition is chosen.
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.
For online referenced documents, information sufficient to identify and locate the source shall be provided. Preferably,
the primary source of the referenced document should be cited, in order to ensure traceability. Furthermore, the
reference should, as far as possible, remain valid for the expected life of the document. The reference shall include the
method of access to the referenced document and the full network address, with the same punctuation and use of upper
case and lower case letters.
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 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.
[1] ITU-T Recommendation P.56: "Objective measurement of active speech level".
[2] ETSI TS 102 250-1: "Speech Processing, Transmission and Quality Aspects (STQ); QoS aspects
for popular services in GSM and 3G networks; Part 1: Identification of Quality of Service criteria".
[3] ETSI TS 102 250-2: "Speech Processing, Transmission and Quality Aspects (STQ); QoS aspects
for popular services in GSM and 3G networks; Part 2: Definition of Quality of Service parameters
and their computation".
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] IETF RFC 3501: "Internet message access protocol - version 4rev1".
[i.2] IETF RFC 2177: "IMAP4 IDLE command".
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9 ETSI TS 102 250-3 V1.4.1 (2008-12)
[i.3] IETF RFC 2821: "Simple Mail Transfer Protocol".
3 Definitions and abbreviations
3.1 Definitions
For the purposes of the present document, the following terms and definitions apply:
A party: in direct transactions, the party initiating the transaction (calling party)
NOTE: In store-and-forward transactions, the party sending content.
B party: in direct transactions, the termination or counterpart of a transaction
NOTE: In store-and-forward transactions, the party receiving content.
content: entirety of information transferred within a transaction, seen from the user's perspective
NOTE: In case of services requiring entrance procedures (e.g. server login with FTP), information flow to
achieve the state of being able to transfer actual user data is not counted as content.
EXAMPLE: Single SMS in SMS service; single multimedia message consisting of video, audio, and text
components in MMS service.
direct transaction: real-time transaction between two entities
maximum expected delivery time: for store-and-forward services, this defines the time span within which a message
shall be received by the B party to rate the transaction successful from the user's perspective
service family: group of services having main characteristics in common
EXAMPLE: Speech and Video Telephony, as well as SMS and MMS, are assumed to form a service family.
store-and forward transaction: transaction where information is sent from one party A to another party B using an
entity C to store information sent from A and attempting to deliver it to B
transaction: single, complete, typical usage of a particular service
NOTE 1: At the beginning of each clause describing a particular service or family of services, the typical
transaction for this particular service is described.
NOTE 2: Each type of transaction has parameters. The sum of all parameters describes the transaction completely.
A parameter set is assumed to be complete if, under constant outer conditions, all transactions using this
parameter set provide the same result.
transaction result: set (list) of possible outcomes for a particular transaction
NOTE: Services belonging to the same service family share the same set of transaction results.
3.2 Abbreviations
For the purposes of the present document, the following abbreviations apply:
AOV Angles Of View
APN Access Point Name
CS Circuit Switched
CSD Circuit Switched Data
DNS Domain Name Server
FTP File Transfer Protocol
GGSN Gateway GPRS Support Node
GPRS General Packet Radio Service
HTTP Hyper Text Transfer Protocol
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10 ETSI TS 102 250-3 V1.4.1 (2008-12)
IP Internet Protocol
KPI Key Performance Indicator
MEDT Maximum Expected Delivery Time
MMS Multimedia Messaging Service
MO Mobile Originated
MOF Mobile Originated to Fixed
MOM Mobile Originated to Mobile
MOS Mean Opinion Score
MS Mobile station
MT Mobile Terminated
MTM Mobile Terminated, originator is also a Mobile unit
MTU Maximum Transmission Unit
PC Personal Computer
PDU Packet Data Unit
PS Packet Switched
PSD Packet Switched Data
QoS Quality of Service
SMS Short Message Service
SMSC Short Message Service Centre
TCP/IP Transmission Control Protocol/Internet Protocol
UDP User Datagram Protocol
UE User Equipment (terminal, mobile station)
URL Uniform Resource Locator
WAP Wireless Application Protocol
4 Goal of measurement
The goal of measurements described in the present document is to assess the network under test for its quality
parameters as defined in TS 102 250-1 [2]. This is, to determine the network quality for the respective transactions from
subscribers view.
5 Classification of services
5.1 Classification guidelines
For the purpose of the present document, services are classified using what is considered to be their dominating
property. The first distinction is made between direct and store-and-forward services:
• Direct-transaction services are services where there is - in the user's perception - a direct end-to-end
connection.
• Store-and-forward services are services where content is stored in the network and delivered to the recipient to
a later point in time.
As a technically usable distinguishing question, a service is considered to be direct if it is possible to decide on
end-to-end content transfer success from the initiating party (A party) of the connection within the scope of the
transaction itself.
For a second classification within direct services, the typical nature of content flow is used for classification:
• In telephony services, content flow is typically symmetrical between the parties.
• In data-access services, content flow is typically - within a single transaction - unsymmetrical.
Of course there are borderline cases, such as voice mailbox services, voice over IP or messaging. Such services are, for
the time being, not treated within the scope of the present document.
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11 ETSI TS 102 250-3 V1.4.1 (2008-12)
5.2 General structure of service descriptions
In the following, each service family description will contain the following structural elements:
• A "family general" part defining:
- the basic transaction definition and if applicable, transaction types;
- a description of the transaction phase combined with a table of parameters governing transaction
behaviour in this phase;
- a description of all possible outcomes of a single transaction;
- a description of content quality measurement definitions (if applicable).
• For each service within the service family, if its respective description differs from the "family general" one, a
set of descriptions for this service, having the same structure as above.
6 General aspects for all types of services
6.1 Set-up and control
Measurements should be conducted in a way that user behaviour is emulated, with a number of parameters under
control of the measurement equipment.
The test case design (configuration and user profile) - to the degree necessary to fully reproduce the test - shall be part
of the report.
It is assumed that for all types of services under test, a testcase consists of a number of single identical transactions. The
measurement equipment and control must ensure that the starting conditions are the same for each transaction. This
includes, among other things, that pause times are sufficiently long that the equipment is in a stable (idle) state again.
The parameter "guard time" sets a minimum value for the pause between transactions.
It is assumed that the measurement is performed by a mobile measurement unit; depending on type of measurement,
other equipment connected to the fixed network is added.
It is assumed that all QoS-relevant transaction parameters are recorded for proper post-processing and are kept constant
during a test. If a test contains more than one parameter set, evaluation shall be made for each parameter set separately.
6.2 Phase and result classification
In order to ensure common wording, the following clause defines terms and definitions for services testing.
It is assumed that each transaction can be described at least by one seamless sequence of phases. There may exist
several Angles Of View (AOV), each leading to a different phase description.
EXAMPLE: Internet services (as described by KPI defined in TS 102 250-2 [3] model A and B). AOV differ
here by different assumptions on start of service usage. Each AOV, however, is a consistent
description by seamlessly connected phases.
Phases maybe further be described having sub-phases.
Pauses between transactions are not explicitly mentioned in this picture, but are relevant with respect to parameter
reporting. Typically, there is a minimum pause (guard time) ensuring that the system under test is in a stable starting
condition for the next test. Values are technology-dependent.
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12 ETSI TS 102 250-3 V1.4.1 (2008-12)
6.2.1 Phase and result classification for direct services
A direct transaction consists of two top-level phases: Service access and service usage.
Table 1
Phase Sub-phase Definition
Service access All steps leading to the technical ability to do actual
user-perspective content transport between A and B
party. Service access may consist of different
sub-phases, e.g. Network access, IP service access and
Internet access. Which sub-phases actually exist
depends on the particular service.
Network access Basic access to the network under test. Successful
network access is assumed when the UE is able to do as
much basic communication with the network as is
necessary to initiate the next phase in the service access
procedure.
IP service access Basic access to the generic packet-data transfer
capabilities the particular service is based upon.
Internet access Basic access to those internet services the service is
meant to provide.
Service usage Content transfer between A and B party.

A direct transaction may have one of the following overall results.
Table 2
Result Definition
Failed Phase of service usage not reached.
Successful or failed service access may be broken down into diagnostic
sub-categories. The general name-forming rule is: result.
Example: Network access failure; IP service access success.
Completed Data-transfer transactions: All content intended to be transferred has been
successfully transferred.
Conversational transactions: The intended transaction duration has been reached.
Dropped Service usage was ended before completion.
NOTE: If a transaction being in the service usage phase is stopped due to some timeout or due to other criteria
by the measurement system, e.g. to enhance test rate, this shall be treated as a dropped transaction.
This behaviour has to be recorded by the measurement system.

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13 ETSI TS 102 250-3 V1.4.1 (2008-12)
6.2.2 Phase and result classification for store-and-forward services
A S&F transaction consists of two top-level phases: Content sending and content delivery.
Table 3
Phase Sub-phase Definition
Content sending All steps required to move the content to the network, up
to the point where the network is able to start delivery.
This phase is completed when there is nothing more the
A party can/needs to do to move content to the B party. It
is assumed that the A party gets information sufficient to
judge if sending has been successful or not.
Content delivery All steps to transfer the content to the B party. Delivery
may consist of two main sub-phases: notification and
retrieval.
Notification Information to the B party that content is ready for
transfer.
Retrieval Transport of content from network to B party, initiated by
the B party.
NOTE: Technically, existing S&F transaction types both SMS and MMS have these phases; however, notification
in SMS is integral part of L3 protocol while in MMS two different media (SMS and WAP) are used.

A S&F transaction may have one of the following overall results.
Table 4
Result Sub-category Definition
Completed Content was successfully transferred from A to B party.
Failed Content was not successfully transferred from A to B part.
Depending on particular services and available in formation, there may be a number
of possible sub-categories for this result.
Undelivered Content was successfully sent to the network, but was never (or: not within a given
period of time, see note) delivered.
Send failed Content was not successfully delivered to the network.
Lost Content was successfully sent to the network, but notification was never received by
A party. Diagnostic sub-category in case notification can/shall be technically
identified within the delivery process.
NOTE: If a Transaction was completed, but content delivery time was above a given threshold, it shall be treated
as Failed, sub-category Undelivered.

7 Telephony measurements
This clause deals with telephony services. In general, the term "content" will be used throughout this clause for the
information flow exchanged between subscribers during a call. Depending on the type of service, content can be audio
or audio and video.
7.1 General aspects
7.1.1 Transaction definition and transaction types
The basic transaction for telephony testing is equivalent to a single call to a counterpart extension. It is assumed that the
call partner is typically a fixed-network type extension to avoid uncertainties related to a second mobile connection.
Type is either Mobile Originated (MO) or Mobile Terminated (MT).
It is assumed that once a connection has been established, for further measurements it does not matter which side has
triggered it. Therefore, the audio data flow parameter will not be logically linked to the call type.
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14 ETSI TS 102 250-3 V1.4.1 (2008-12)
7.1.2 Parameter overview
Table 5
Phase Parameters
Service Access Call counterpart. This includes the type of equipment (dedicated unit, automatic reply
with taped message, etc.).
Call type
Time-out for failed-call condition
Service Usage Call duration
Content flow direction: This is an inner parameter for a transaction. Basically, all
combinations of uplink/downlink dynamics are possible:
- Uplink only;
- Downlink only;
- Conversational (alternating uplink and downlink). This is the recommended
standard testing mode. Other testing modes are considered to be used only for
special purposes;
- "Duplex" (uplink and downlink flow simultaneously).
Codec settings
Call clear-down Guard time
Pause Pause duration. For current GSM equipment, a pause time of at least 15 seconds
(guard time) is recommended.
However, this duration may be adjusted to local conditions or special testing goals, but
this must be reported.
If the pause duration is too short, side effects may occur, resulting in all kinds of
transient effects and distortions in measurement data. It should be made certain that
all the QoS parameters to be measured are not affected by the pause time.

The last transaction within a test sequence does not require a pause.
7.1.2.1 Additional considerations
Regarding call timing including behaviour in case of dropped calls. For reasons of comparability in density, it is
required that all call attempts which form part of the statistics must follow a constant time pattern. Additional call
attempts must not affect the pattern of the statistically relevant call attempts (see figure 1).
Call (set-up, connection, clear- Failed or
Regular call pattern Pause Pause
down dropped call
Additional call (max.
Additional activities duration)

Figure 1
7.1.3 Additional transaction result definitions
For call set-up assessment beyond QoS data acquisition, typically a state model driven by Layer 3 information
combined with information from the call control engine is being used. This state model may also be used to determine
timing information for each phase.
Service usability, i.e. presence of a usable two-way connection, shall be verified by a procedure based on content test
transmissions within a given time window. If within this time window no connection can be verified, the setup attempt
shall be considered to be failed and the call attempt be terminated.
A call is active only as long as both sides consider it to be active. A call is therefore considered to be dropped if either
side detects a dropped call.
Above definitions lead to the following decision tree for the outcome of a call (figure 2 includes the end-of-call cases).
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15 ETSI TS 102 250-3 V1.4.1 (2008-12)
Call Attempt
Access Failure
Successful network access
Setup Failure
Setup Succ
...