Test equipment

Written on 4:13 PM by ooe

The technical specification of the unbundled line forms a part of the contract between network owner and the LLU operator. It is important that the network owner is able to test the lines before provision and during maintenance activities. BT has invested heavily in test equipment for use on its conventional telephone lines and it was logical that the same equipment should be used to test unbundled lines. The connection between the test equipment and the metallic line is a part of the local exchange concentrator but this is not connected to unbundled lines. The short term solution to this problem was to provide a physical test point connected to the unbundled metallic path near the point where the tie cables were connected to the MDF. When a test was needed on an unbundled line a BT engineer had to visit the MDF and make a manual connection between the line test systems and the metallic path test point. A further visit was required at the end of the test period. This solution was simple to implement but relatively slow and manually intensive to operate.

BT has decided that the longer term solution to the test problem is to connect all the unbundled lines through a specially provided test access switch matrix. This device simply automates the process of connecting the test equipment to the line. This could not be adopted at the initial launch of LLU products owing to the time taken to specify and procure a switch matrix and in particular to integrate it into BT support systems and processes. The test matrix will allow tests to be carried out more quickly than the manual test solution allows.

This test solution is appropriate for both full unbundling and line sharing. It is not appropriate for sub loop unbundled lines which do not connect to the local exchange site. A different approach must be developed if these lines are to be tested without manual intervention.