Abstract
Researchers involved with the project MC3 are concerned with the functional specification and architecture definition of a new ASIC (application-specific integrated circuit) data communication circuit intended for the high-level International Standards Organization (ISO) protocols Network, Transport, and Session. A specific data structure, called PnPDU (processing level n protocol data unit), has been defined for frame memory management in the implementation of these protocols, particularly when 2 or more protocols are to be implemented jointly on a data communication circuit and when the minimization of computational costs is an important design criterion. Goals in defining the structure included: 1. achieving independence from the implemented layer, and 2. accounting for all of the functionalities described in the ISO protocols. The MC3 circuit architecture involves 6 parallel processors, each dedicated to a different task. The micro-architecture of the Transfer Machine is dedicated, inside MC3, to the interface management and to the frame emission and reception.