Working groups of the DLMS User Association make an essential contribution to the success of DLMS/COSEM. Because of the growing membership of the DLMS UA, the new implementations and the increasing market presence of DLMS/COSEM-based systems, the working group 'Maintenance' is very active these days.

The task of the members of this working group is to maintain the specification and the conformance test tool. Questions and issues arising during the implementation of the protocol and during conformance testing are collected, analysed, discussed and answered. The deliverables are interpretation notes, and when necessary amendments to the coloured books and to the international standards or to the test plans.

The main topic of the recent meeting of the Maintenance WG was the preparation of documents specifying the TCP/IP-based communication profile, allowing meter data exchange using the Internet. Pending requests and remarks from members of the DLMS UA have been reviewed and discussed; these are regular items on the agenda.

One of the important tasks is the definition of the maintenance process itself. The web site of the DLMS User Association plays an important role in this: it allows all items to be logged, published and debated, and their progress is tracked until they are closed.

In the past few months many requests have been received concerning new standard OBIS codes. These are the unique identifiers of COSEM interface objects, allowing unambiguous identification and interpretation of new data items needed in liberalised markets. These requests clearly show that users have well understood the importance of using standard codes instead of manufacturer-specific codes. The flexible structure and mechanisms of the OBIS system will allow all these requests to be met, if we use the code space available sparingly.

The Maintenance WG will publish ongoing work on the Internet, allowing all users fast access to actual data.