Establishing the SDLC Primary/Secondary Relationship on Switched Communication Links
Original Publication Date: 1983-Jun-01
Included in the Prior Art Database: 2005-Feb-07
The synchronous data link control (SDLC) protocol is widely used in data communication. When using SDLC protocol in normal response mode on switched links, a primary/secondary relationship must be established between the two terminals. In the typical host-to-terminal SDLC connection, the host is customarily designated the primary, and the terminal is secondary. However, advanced function terminals are now able to talk to other non-host terminals. In this peer-to-peer environment, a determination of the primary/secondary relationship must be established for the two terminals. In order to prevent endless contention as to which is the secondary and which is the primary, the hardware of the present expedient utilizes a random number generator. This permits a quick determination of primary and secondary relationships.