| Summary: | 碩士 === 國立交通大學 === 資訊管理研究所 === 81 === The Fiber Distributed Data Interface (FDDI) is a high speed
local area network (HSLAN) operated at 100 Mbps using the fiber
optic ring transmission medium. It uses a timed token rotation
protocol. The FDDI medium access control (MAC) priority
mechanism supports two classes of traffic : synchronous and
asynchronous. The asynchronous class makes provision for up to
eight different priority levels. The performance of FDDI is
closely related to its operational parameters, such as the
number of stations on the ring, the frame size, the Target
Token Rotation Time (TTRT), and the Synchronous Bandwidth Timer
(ST). The purpose of this paper is to analyze the delay time
and throughput of the FDDI MAC protocol while both the
synchronous and eight asynchronous traffic are presenting. We
focus out attention on the rela- tionship between the FDDI
performance and ST. A simulation model, which is based on the M/
G/1 cyclic queue service discipline, is developed. Two
configurations, with 45 and 100 stations each, have been
studied. From the simulation results obtained, we are able to
propose several operational guidelines for setting ST. We
conclude this thesis with a delay prediction procedure. This
procedure, which is developed by incorporating Lagrange''s form
of the interpolating polynomial, can predict the mean frame
delay within 1.5 percent of the simulation value. The
prediction procedure in conjunction with operational guidelines
provides an effect tools for tunig the FDDI network.
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