compatible class
2.In this paper, we present a formal description of a NEUT transport protocol(NEUT-TP4)using Estelle,which is compatible with the ISO class 4 transport protocol, and a semiautomatic implementation of it using an Estelle -C compiler. We find the semiautomatic approach offers several advantages over conventional manual method, including correctness and modularity in protocol implementation code, confirmance to the specification, and reduction inimplementation time.
3.By using the compatible and subcompatible conditions of self-mapping pair in metric spaces,the existence of common fixed point for a class of contractive mappings in complete metric spaces was discussed.A new common fixed theorem is obtained.
4.SDH has the unified network node interface (NNI), standardized information class structure in all the world and can be compatible with PDH, which makes all the transmission network systems can communicate with each other on the level of STM-N.
5.SDH possesses the unified network node interface (NNI) and standardized information class structure in the world. SDH can be compatible with PDH. It makes all the transmission network systems can communicate with each other on the level of STM-N.

