A Modified ISDN Network Layer Protocol Suitable For Implementation In Hardware
Jeffrey J. Brown, Witold A. Krzymień · INFOR Information Systems and Operational Research · 1989
The paper discusses a modified ISDN signalling system's network layer protocol for point-to-point links suitable for processing in VLSI. a reduction to CCITT recommendation Q.931 is proposed. The need for bearer channel negotiatioris is eliminated by using a symmetric “two-way independent channel selection” technique in which each end of the link is master in the transmit direction and slave in the receive direction. A logical model for the signalling system's network layer processor is developed to aid in understanding the Q.931 protocol. The model also serves as the initial functional partitioning for a VLSI implementation. The key element of the model is the separation of the network layer processor into a protocol specific module (PSM) and an application specific module (ASM).