الفهرس 
AcknowledgementOnly 14 pages are availabe for public view
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Abstract
The problem of computer network design is investigated in this thesis.
design will consider local-a.rea as well as long-haul networks. The de
sign process will be general so that other types of networks such as :
telephone lines, railways, traffic, ... etc., can be considered by making
slight modifications of the parameters which control the design.
The objective of the design is to minimize the cost of allocating com
mmication links between different sites while maintaining the maximum re
liability and minimum delay time requirements; an algorithm is introduced to solve such a problem. It deals with a number of geographically distrib¬.:-ed computer sites and tries to allocate channels between them. The cha.n
nels are assigned prespecified capacities and the algorithm selects the one
which fits the required bus load. An over-load factor is introduced to the
design to guarantee a certain safety factor which is determined according
to the load nature. The algorithm considers that the network is functioning
as long as there exists a path between each pair of nodes -i.e. connected.
Two sorts of cost factors are contributed to the design : the termination
cost, which is the cost of interfacing an extra link to an Interface Mes
sage Processor (IMP), and the cost per unit length of a certain channel type which is proportional to the channel capacity.
Some problems in the design had been overridden, such as, no restriction
is imposed over the network connectivity (K); the network is designed to maintain a prespecified load which is estimated according to the amount of
message-flow between each pair of nodes. This message-flow can be estimated
from historical or natural data or even political objectives that may have
a great influence over the nature of traffic coincident to the network, so, different probabilities are associated with each node to send a message to
another.