Project Description
Token-Ring LAN
Simulation modeling and performance analysis of networks including
traditional local networks such as token-ring and high-speed networks such
as FDDI have been conducted.
The token-ring local area network protocol (IEEE 802.5) was
simulated using CSIM, a process oriented simulation language based on C.
The model behavior was analyzed and its and its performance was compared
with an analytical model. The effect of buffer size and service schemes on
the network performance was studied.
Analytical and simulation models for studying the effect of integrated
traffic (voice and data) on a token-ring network have been developed which
can be extended to video traffic as well. The model provides the
selection of optimum voice packet length, maximum number of voice stations
that the network can support, relationships between voice packet delay and
number of voice stations and between voice and data traffic in the same
network, and statistical characteristics of voice packet delay. This can
be used as practical design rules for implementing multimedia integrated
services using existing technology and standards.
A dynamic protocol for token-ring network with unbalanced load conditions
was designed by selecting the value of token_holding_time according to the
load (or the queue length) at the node. This achieved both fairness in
and better performance in terms of reduced waiting delay and buffer
occupancy.
For Details See the Relevant Publications
FDDI
Simulation modeling and performance analysis of networks including
traditional local networks such as token-ring and high-speed networks such
as FDDI have been conducted.
A simulation model to analyze the performance of FDDI MAC protocol has
been developed and formulated a procedure to select and tune FDDI network
parameters to obtain the best possible performance under different
operating conditions. An analytical model to estimate the throughput of
FDDI network with synchronous and asynchronous traffic was established and
the boundary condition and stability of this network was studied.
Fault-tolerant design for dual-ring networks
A dual-counter rotating rings such as FDDI with reconfiguration capability
can enhance the network fault-tolerance. In this project, an automatic
failure isolation and reconfiguration methodology (FIRM) was developed for
dual counter-rotating ring networks to detect, locate, and bypass physical
failures. The strategy is to significantly improve the network
reliability with maximum possible connectivity and without increasing the
network length. A software implementation of the FIRM algorithm have been
carried out.
For Details See the Relevant Publications
Integrated Services Support in MAN-ATM
Networks
The main objective is to support integrated services in a MAN (DQDB
subnet) internetworked with ATM while satisfying the QoS requirements.
An architecture is presented for the support of integrated services
between two remote MAN users via ATM network. A dynamic bandwidth sharing
scheme via renegotiation for applications with flexible bandwidth
requirements is proposed.
For Details See the Relevant Publications