STF document template - ETSI Portal

|[pic] |ToR STF 512 (TC INT) |
| |Version: 0.6 - Date: 27 January 2015 |
| |Author: TC INT |
| |Last updated by: Alberto Berrini - 14 March |
| |2016 |
| |page 1 of 10 |


Part I - Reason for proposing the STF


Rationale

Call Session Control Functions (CSCF) within the IMS core network are in
charge of handling the signalling of all call session related message
exchanges of User Equipment (UE) connecting through the IMS. Application
Servers (AS) host and execute services, and can be located in the home
network or in an external third-party network. Both the IMS core made up by
its CSCFs and the Application Servers (AS) are relying on data related to
the charging procedures. Offline charging information is provided by the
Charging Trigger Function (CTF) nested in IMS core functions and in AS.
Online charging information is provided by the CTF to the Online Charging
Function (OCF) implemented in the Online Charging System (OCS) for AS, IMS
Gateway Functions (IMS-GW) and Media Gateway Control Functions (MGCF).

The Rf Reference Point that enables transfer of offline charging
information is located between the CTF of Call Session Control Functions
(CSCF) or Application Servers (AS) and the Charging Data Function (CDF)
which is usually co-located with the Charging Gateway Function (CGF) in the
Charging Collection Function (CCF). The Ro Reference Point that enables
transfer of online charging information is located between the CTF of
Application Server (AS), IMS Gateway Function (IMS-GW) or Media Gateway
Control Function (MGCF) and the Online Charging Function (OCF).

The Rf/Ro protocols used on the two above IMS ETSI TS 132 260 Rf/Ro
Reference Points, are specified in ETSI TS 132 229, and rely on the
Diameter protocol as defined in RFC3588.

The architecture for IMS offline charging is described in figure 1.

[pic]

Figure 1: IMS offline charging architecture


The architecture for IMS online charging is described in figure 2.
[pic]

Figure2: IMS online charging Architecture

Given that there are already test specifications related to the Diameter
protocol profile for the Rf and Ro reference points under implementation,
it seems reasonable to validate those test specifications.
Following the methodologies developed and used by ETSI, the validation is
based on the three part Test Specification for the Rf and Ro interfaces,
where part 1 (PICS) has already been approved at the INT#30 meeting
(Vienna, September 7-10, 2015). Approval of parts 2 (TSS&TP) and part 3
(ATS&PIXIT) are planned for INT#31 (December 2015) and INT#32 (March 2016)
respectively.

Experience with the validation of other testing standards has shown that
involvement of experts on conformance testing of protocols requires highly
specialised knowledge in testing methodology, TTCN-3 language and dedicated
tools. There is an advantage if testing experts are disjoint from experts
developing the protocol specifications. In addition, the validation of this
kind of specifications requires significant effort and it cannot be
expected that this effort can be provided on a voluntary basis. Hence the
involvement of testing experts is needed in order to assure timely
completion and high quality of the test adaptors. These testing experts are
not available on TC INT level and need to be recruited on a funded basis.
The experts will use TTCN-3 platforms available at ETSI.
Past ETSI experience has shown that an STF, supported by the ETSI CTI, is
the most effective and cost-efficient way to develop and validate test
specifications.


Objective

Recently major efforts have been made by VoLTE component providers to inter-
connect complete networks, i.e. connecting the single components that
comprise an VOLTE network of different operators to allow seamless roaming
for end customers and complete and reliable functionality for network
providers. Billing is the most important topic for network operators as the
revenue generated through traffic on their networks is the main income
factor for them.

Given that all the test specifications related to the Diameter protocol
profiles developed so far (for Rx, Gx, S6a, S9, Cx and Dx reference points)
have been validated by STF450, STF482 and STF500 against equipment of a
significant number of vendors, it seems reasonable to extend the INT set of
validated test specifications to also cover Diameter on the IMS Rf and Ro
reference points. Members of INT have already expressed the wish to provide
access to equipment to validate against.

Experience with the validation of other testing standards has shown that
involvement of experts on conformance testing of protocols requires highly
specialised knowledge in testing methodology, TTCN-3 language and dedicated
tools. There is an advantage if testing experts are disjoint from experts
developing the protocol specifications. In addition, the validation of this
kind of test specifications requires significant effort and it cannot be
expected that this effort can be provided on a voluntary basis. Hence the
involvement of testing experts is needed in order to assure timely
completion and high quality of the Test Specifications. These testing
experts are not available on TC INT level and need to be recruited on a
funded basis. The experts will use dedicated software tools available at
ETSI.


Relation with ETSI strategy and priorities

This STF is directly related to ETSI strategic objective "Major Strategic
Topics - NGN" and "Service level interconnection of IP-Based Services" and
corresponds to the "Standards enablers/facilitators (conformance testing,
interoperability, methodology)" category.


Context of the proposal


1 ETSI Members support


|ETSI Member |Supporting |Motivation |
| |delegate | |
|Telecom |Giulio |Tests used to get detailed information from |
|Italia |Maggiore |vendors about Interoperability Testing before|
| | |coming to the market |
|Telekom |Martin Brand|Tests needed for internal network testing |
|Austria | | |
|Deutsche |Gerhard Ott |Tests needed for internal network testing |
|Telekom | | |
|AT&T |Dewayne |Tests used to promote conformance testing for|
| |Sennet |Public Safety |
|Telekom |Matjaz.Beric|Test used to promote interoperability among |
|Slovenjia |ic |vendors |
|Cisco |Jesus |Test will be used for quality enhancement of |
| |Trujllo |IMS&EPC products |
| |Gomez | |
|ZTE |David Huo |Test will be used for quality enhancement of |
| | |IMS&EPC products |
|Iskratel |Primo? Ko?ar|Test will be used for quality enhancement of |
| | |IMS&EPC products |
|Italtel |Diego Saiu |Test will be used for quality enhancement of |
| | |IMS&EPC products |
|Arcatech |Terence A, |Provide test system for functional and |
| |Simpson |performance test. |
|Codenomicon |Ari Takanen |Provide test system to test protocols |
|Confomiq |Stephan |Generation of tests for testing protocol |
| |Schulz | |
|Testing Tech|Theofanis |Provide the Test System for the test cases |
| |Vassiliou-Gi|implementation and execution |
| |oles | |
|Fokus |Axel Rennoch|Research Institute, advanced |
| | |automated/standardized test solutions with |
| | |TTCN-3 |
|Elvior |Andres Kull |Tool Provider, Provide the Test System for |
| | |the test cases |
|Tektronix |Gruyer, |Tool Provider, Provide the Test System for |
|Communicatio|Martial |the test cases |
|ns | | |
|Keynote |Shicheng Hu |Try to establish the synergy between the |
|Sigos | |network conformance and the network e2e |
| | |tests. Provide the Test System for the global|
| | |roaming and the e2e QoS / QoE tests |
|BNetzA |Wolfgang |Provide and evolve tools based on end user |
| |Balzer |devices (e.g. smartphones with respective |
| | |apps)to create stimuli (scenarios where |
| | |DIAMETER communication is invoked) for |
| | |testing, and to interpret system responses |
| | |from an end to end QoS perspective |
|Sintesio |Bostjan |The aim of the SINTESIO Foundation is to |
| |Pintar |promote ope