Viet Nam‘s contributions to Interoperability and
Conformity Assessment workshop
I. Introduction
Nowadays, telecom equipments’ generations are being changed and developed quickly with more capacity and higher processing capability product lines. Therefore, for developing countries like Viet Nam, investment of an ICT system to supply services to customers can be implemented with many choices of technologies and equipments.
Almost all telcos have networks consisting of products and equipments from many different vendors and suppliers. Although most of vendors and suppliers’ equipments are compliant to international standards, there are still some arisen matters while integrating equipments of different suppliers.
Along with the swift development of product families and vendors, telecom companies (telcos) in developing countries like Viet Nam are facing many difficulties in testing, assessing the quality of system equipments and their influence on general quality of service delivered to customer. Some examples of difficulties are explained as following.
II. Problems
1. Partial missing of vendor’s committed implemented functionalities affects general quality of services
- When teclos purchase and import equipments to build the telecom and IT networks to provide services to customers in Viet Nam, there is no separate organization or office responsible to verify and assess the quality and functionality pre-declared by vendors. On the other hand, telcos don’t have sufficient experience in verifying quality and capacity of the systems as well as a standard Test Lab to conduct the testing and conformity assessment of the equipment’s quality. This matter will affect the quality of service delivered to customers.
- Examples: In mobile wireless network, it was not possible to implement vendor A’s EMR function (to report the network quality form the MS) even though this function was committed in technical descriptions and other official documents. In transmission network, vendor B’s SDH equipment Metro 100 lacks of LCAS (Link Capacity Adjustment Scheme) functions….
2. Partial lack of interoperability between equipment of same or different manufacturers results in the impossibility to access to services
- At present, ITU recommendations and 3GPP specifications may have many optional features and parameters. Suppliers sometimes choose only some but not all those optional features and parameters, this leads to incompatibility of equipments from different suppliers. The similar incompatible problems will takes much time of both suppliers and telcos to be solved.
- Example 1: In Telco C’s case, when implementing the mobile network at the Sigtran and BICC layer, for the same AMR coding standard of softswitches, supplier E and supplier F use different speech sampling timeslot (supplier E uses 5 ms and supplier F uses 20 ms). And when exchanging codecs between 2 softswitches, the first priority of supplier F’ MSS equipment is AMR 12.2 while AMR 12.2 is the secondary choice of supplier E’s MSS, thus, the supplier E’s MSS only replies with the G.711 message. The consequence is that the 2 softswitches of supplier E and supplier F could not successfully exchange the AMR speech messages. This matter took Telco C 2 months to solve and neither suppliers took responsibility of this delay.
- Example 2: When connecting supplier E’s BSC to supplier F’s MSS, there is incompatibility of counting criterion for messages, resulting mis-counting of call-drop reasons, thus the statistical figure is not exact. This issue also affects the monitoring of network quality directly. Besides, the A interface of supplier E‘s BSC support only ATM while the MSS equipment of supplier F support only TDM. This problem again took a long time to get the 2 equipment operate together.
- Example 3: For EoS service (Ethernet over SDH), equipments of many suppliers can not be configured inter-networking (in fact, in telco C’s case, equipments of supplier E, F, H could not be inter-networking configured).
- Nowadays, almost all exchanges in the mobile core network are changing to softswitches and signaling methods are changing to Sigtran and SIP but Viet Nam hasn’t had enough experience in assessing the conformity of those signaling scheme standards.
3. Need to apply unexpected procedures to obtain that functionalities work
- Some telcos in Viet Nam have already been implementing IPTV services but ITU hasn’t recommendations on implementing IPTV on IMS. Therefore each telco has to look for another standard body or forum to refer to.
- In NGN system, there is lack of ITU recommendations to map in while the development of new end-user equipments and network equipments is getting more and more diversified.
- Example: For NGN network that provides VoIP and multimedia services, there are many types of end-user equipments such as ATA, HomeGateway or IP phones but it is not true that every terminal will be compatible with the existing NGN that Telco has already invested using equipments from one supplier.
4. Equipment lack of conformity with standards
- Almost all equipments supplied by vendors to build the network are declared to be compliant to international standards but there are not concrete proofs or clear binding. Mandatory and optional terms are applied in different way for each operator/telco or supplier. Optional features can affect connections and interoperability between equipments and quality of service.
5. Low quality of service
- While SLA connects closely to the technical quality of services in the sense of satisfying different level of service quality to different customers, the implementation of SLA of Vietnamese service providers has not yet been carried out. In Viet Nam, many service providers/operators could not figure out the specifications that are related to the QoS of each service, thus their compatibility or incompatibility to ITU recommendations such as ITU-T G.1010, ITU-T E.860… still can not be verified.
- End-to-end SLA can relate to connection between different operators/service providers, thus it is necessary for service providers to commit the connection quality among themselves before committing the SLA with end-user customers.
- In almost all service networks in Viet Nam, QoS has not been realized in details, therefore it is not easy to apply ITU-T’s recommendations.
6. Other matters
- Viet Nam hasn’t completed the building of our own QoS standards system yet, therefore, due to economical competition, operators/telcos often choose the cheaper equipments when developing their networks, this would lead to unreliable quality, affecting directly to QoS and customer’s experience.
III. Proposals
In fact, apart from above problems, there are also many other non-interoperability between telecom equipments. In dealing with these issues, developing countries like Viet Nam still have less experience.
- We propose that ITU will open a channel to assist telcos to solve all mentioned problems.
- For NGN case, we propose that suppliers of system equipments and terminal equipments to cooperate closely with standardization organization for easier assessment of conformity and interoperability.
- Viet Nam call for ITU’s assistance and sponsoring for training and building a standard Lab for assessing and testing quality and capacity of telecom network equipments (not only terminal equipments) from suppliers. We also recommend that the responsible division/department of ITU to help telcos and request vendors to cooperate with telcos in dealing with non-interoperability.
- Viet Nam expects that ITU would produce guidelines for developing countries in applying ITU recommendations and build our own national standard system for NGN/IP/3G in which specifications and parameters are chosen suitable with the conditions of Viet Nam as well as other countries in the region.
- ITU should consider holding the workshop on the administrative role in conformity assessment including best practice and experience of developed countries in this issue.
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