SAFENET AND FDDI PERFORMANCE EVALUATION TOOL

THE PURPOSE OF OUR PROPOSED WORK IS TO USE THE ANALYTICAL INNOVATIVE TECHNIQUES WE HAVE BEEN DEVELOPING TO DEVELOP IN PHASE I EFFICIENT ANALYTICAL METHODS THAT CAN THEN BE USED IN PHSE II FOR THE DEVELOPMENT OF A SOFTWARE TOOL CONDUCTING PERFORMANCE EVALUATION FOR SAFENET II AND FDDI LOCAL AREA NETWORKS. OUR PROPOSED TOOL ENCOMPASSES THE KEY DELAY-THROUGHPUT PERFORMANCE MECHANISMS INVOLVED IN THE END-TO-END COMMUNICATIONS PROCESS. DETAILED PERFORMANCE ANALYSIS PROCEDURES ARE FIRST DEVELOPED TO COMPUTE AVERAGE, MAXIMUM AND VARIANCE LEVELS FOR MESSAGE DELAY, BUFFER-SIZES AND THROUGHPUT INDICES FOR THE MEDIUM ACCESS-CONTROL LAYER, WHICH UTILIZES THE FDDI TIMED TOKEN ROTATION PROTOCOL. SYNCHRONOUS AND MULTI-PRIORITY ASYNCHRONOUS MESSAGE CLASSES ARE CONSIDERED, UNDER A MULTITUDE OF TRAFFIC AND SYSTEM CONFIGURATION CONDITIONS. PURE ANALYTICAL AND JOINT ANALYTIC/NUMBERIC APPROACHES ARE DEVELOPED. A DETAILED SIMULATION MODEL RECENTLY DEVELOPED AT IRI IS USED TO VERIFY AND CALIBRATE THE ANALYTICAL SCHEMES. IN ADDITION, QUEUEING MODELS ARE INTRODUCED, IN A LAYERED FASHION, TO ACCOUNT FOR MESSAGE DELAYS THAT OCCUR AT THE LLC AND TRANSPORT LAYERS, INCLUDING COMPONENTS INDUCED BY MULTIPLEXING, ERROR CONTROL AND FLOW CONTROL SCHEMES EMPLOYED BY TP-4 OR XTP TRNSPORT PROTOCOLS, AS WELL AS FOR COMPONENTS INTRODUCED BY PROCESSING DELAYS AT THE USER AND APPLICATION LAYERS.