The paper describes the design of the X.25 module in a formal way, i.e. in terms of specifications. The X.25 module provides functions, by means of which message link level protocols can be implemented; these functions' specifications strictly follow the X.25 recommendations.
['Sigram Schindler', 'Jochen Didier', 'Michael Steinacker']
Design and Formal Specification of an X.25 Packet Level Protocol Implementation