Current Research
Interests: Performance
analysis, modeling and simulation of broad-band wireless networks,
multimedia networks, 4G mobile and ATM networks.
A. Current Research
(with Faisal Iradat):
Abstract :
A major challenge in
the design of high-speed networks is an effective and flexible
access network. Demand for higher speeds and availability of
improved technologies has resulted in wide spread deployment of
broadband access technologies. However due to the increased costs
and cumbersome processes associated with wired infrastructures such
as DSL, T1, and cable modems, wireless access infrastructures have
promised an exciting and highly welcomed alternative. The recently
introduced broadband wireless access standards such as IEEE 802.16x,
IEEE 802.20, and 4G mobile networks are expected to provide the much
needed alternatives to wired access. Our research aims at exploring
such upcoming broadband wireless access networks with focus on
performance modeling and analysis. In particular our analysis
suggests that alternative access technologies such as CDMA may be
effectively applied in the upcoming technologies as compared to
DAMA-TDMA schemes currently in use, to achieve improved quality of
service, especially for short duration, bursty traffic patterns.
B. Recent
Publications with Abstract:
1. S.
Ghani and M. Schwartz, "A decomposition approximation for the
Performance Evaluation of Non-Preemptive Priority in GSM/GPRS,"
accepted for publication to The First International Conference on
Broadband Networks (Broad Nets 2004), to be held in San José,
California, USA, on October 25-29, 2004.
Abstract:
Decomposition
Approximations have in the past been successfully applied to the
performance analysis of Preemptive Priority based GSM/GPRS networks.
In this paper we propose a decomposition technique for the
performance analysis of GSM/GPRS networks where GSM voice calls have
non-preemptive priority over GPRS data packets. In other words when
demand exists for GSM circuit switched channels the GPRS user can
continue its transmission until the ending of packet transmission
resulting in a delayed release of the channel. It is shown that such
an approximation can be quite accurate in predicting both the impact
of delayed release on GSM voice queuing as well as for comparison of
immediate versus delayed release of channels on GPRS data queuing
delays.
2.
"A Hierarchical Analysis of Access Multiplexers with Multimedia
Traffic", The Ninth IEEE Symposium on Computer and
Communication (ISCC'2004), Alexandria, Egypt, June 29-July 1, 2004.
Abstract:
Approximation
techniques have been used in the performance evaluation of access
networks such as GSM/GPRS and ATM based networks. In this paper we
apply and extend a Decomposition Approximation to the analysis to a
network possessing a hierarchy of traffic types, such as voice, data
and broadband video. We look at different policies for the
transmission of the traffic, and apply a hierarchical Decomposition
technique to the performance analysis of the network where
necessary. We find that the Decomposition technique is quite useful
in predicting the performance of networks where video, voice and
data have channel holding times which are each of different orders
of magnitude in comparison to each other.
3.
"Use of Approximation Methods in the Analysis of Communication
Networks with Heterogeneous Traffic", 1st International
Workshop on Frontiers of Information Technology, Islamabad, December
23-24, 2003.
Abstract:
The Convergence of
various classes of traffic in modern Telecommunication networks has
significantly increased the complexity of performance analysis of
such networks. Exact solutions being computationally intractable, it
is of importance to have analytical approximations that can be used
in various key aspects of such networks such as control of traffic
and optimization of resources. This paper looks at various
approximation techniques used in the past and in particular a
Decomposition Approximation that is valid when heterogeneous traffic
are utilizing shared resources or channels, where the holding times
of the traffic vary greatly. This paper briefly describes the basic
approach of this method and gives examples of the use of such
approximation techniques. Future applications of this method are
also given where this method could be usefully applied.
C.
Research Publications
