Most fields in an overhead area are fields used for a management channel, or are occupied by a management channel. However, these fields are not fully used. In this embodiment of the present invention, a first field is defined in an overhead code block of each physical connection. The first field indicates an identifier of a timeslot configuration table used by a current physical connection, and is used to transmit, when the timeslot configuration table changes, content of a changed timeslot configuration table to a receive end using the management channel. That is, a specific field needs to be defined only for the identifier of the timeslot configuration table in the overhead area, and the content of the timeslot configuration table is transmitted over the management channel. This effectively reduces a waste of overhead resources, and provides higher flexibility.
Optionally, in an embodiment, the management channel is further used to: when a configuration table of the physical connection group changes, transmit content of a changed configuration table of the physical connection group, where the configuration table of the physical connection group is used to indicate an identifier of each physical connection in the physical connection group and a sequence between the physical connections.
Optionally, in an embodiment, the management channel is used to transmit, based on a protocol packet, the content of the timeslot configuration table and/or the content of the configuration table of the physical connection group.
Optionally, in an embodiment, the management channel is further used to negotiate, based on the protocol packet, a change of the timeslot configuration table and/or the configuration table of the physical connection group.