The pointer is used for alignment. Indicates the starting position of the VC in the corresponding AU or TU. In this way: the corresponding VC can be correctly removed from the STMN, and then the VC…

The pointer is used for alignment. Indicates the starting position of the VC in the corresponding AU or TU. In this way: the corresponding VC can be correctly removed from the STMN, and then the VC and C packages are divided into separate low-rate signals, such as PDH: That is to say, the low-rate tributary signal can be discarded directly from the STMN signal.