Date of Award


Document Type


Degree Name

Master of Science


Department of Electrical and Computer Engineering

First Advisor

Richard A. Raines, PhD


This thesis consists of a performance analysis of two network models using different protocols, the X.25 and Asynchronous Transfer Mode (ATM). X.25 is currently used in the data communications network infrastructure in the Brazilian Air Force. ATM is a high speed network technology. Simulations of both models were performed to compare the two technologies. This study examines the traffic load that each network can handle while still providing a good quality of service (QoS). The X.25 network model proved to have a sufficient capacity to handle the projected workload, but it presented a low QoS when a more intense traffic load was introduced. The results obtained from the ATM simulation proved that the ATM model can support much higher traffic loads with no degradation of QoS. This comparison is important since no study of this kind has been realized before and because this network was designed and implemented for a different type of traffic than the one generated by today's applications. The implementation of a high-speed technology will bring many benefits, such as: increased throughput, higher data rates and multimedia traffic.

AFIT Designator


DTIC Accession Number