The present invention is a new solution of line and relay in an analog subscriber board, which has a less number of relays and can decrease the cost and save the space while realizing the basic functions in a voice network. The technical solution of the invention provides each subscriber with two relays to connect the subscriber line interface circuit, the subscriber line, the ring bus and the test bus, realizing the basic functions relevant to the talking, such as talking, ringing, etc. In order to add the auxiliary functions such as the testing function and the monitoring function, the subscriber lines are grouped, and at least one relay is supplemented in a subscriber group, the subscriber group relays together with above two subscriber relays will be used to connect the subscriber line interface circuit, the subscriber line, the ring bus and the test bus to perform the basic functions relevant to talking and the auxiliary functions such as testing, monitoring, etc.