It should be understood that the overhead code block that is transmitted over each physical connection further including fields used for a management channel may be as follows. The overhead code block transmitted over each physical connection further includes a field occupied by the management channel. The management channel may occupy fields of overhead code blocks in multiple manners. For example, the management channel may occupy some fields of an overhead code block; or may occupy all fields (including synchronization headers) of some overhead code blocks. That is, the management channel occupies a whole overhead code block. Certainly, alternatively, a combination of the two manners may be used. This is not specifically limited in this embodiment of the present invention. An example is used for description. In four consecutive overhead code blocks, the management channel does not occupy a field of a first overhead code block, but occupies some fields of the last three overhead code blocks. Alternatively, in 20 consecutive overhead code blocks, the management channel does not occupy any field of the first three overhead code blocks, but occupies all fields of the last 17 overhead code blocks. That is, the management channel occupies the last 17 overhead code blocks.
It should be noted that, a change of the timeslot configuration table used by each physical connection may specifically indicate an update to content of the timeslot configuration table of each physical connection, or may indicate that each physical connection uses a new timeslot configuration table to replace an old timeslot configuration table.