Faculty & Research, Harvard Business School

Dr. Sayeed Ghani

Associate Dean, Faculty of Computer Science


Telecommunications Research Lab (TRL) :

Presently leading the PhD research at the TRL with three PhD students/faculty members:

  • Faisal Iradat
  • Rashid Faruqui
  • Waseem Arain

In the following areas: Performance analysis, modeling and simulation of Mobile Ad Hoc Networks (MANETs); Call admission control in integrated wireless 802.11e voice and data networks; Routing issues in MANETs.

For conducting simulations, we have primarily used NS2, although we have recently started looking into Qualnet as well. The TRL also has a licensed version of Labview.

A. Ongoing Research with Faisal Iradat:

An Integrated Voice and Data Traffic with Call Admission Control Scheme in IEEE 802.11e EDCA Based Wireless LANs.

Abstract :
Wireless Local Area Networks (WLANs) based on IEEE 802.11 are becoming the most widely used WLAN technology for its easy deployment and lower cost. Due to the lack of Quality of Service (QoS) provisioning for integrated services such as voice and data in 802.11, the IEEE 802.11e was proposed. Despite providing service differentiation through priorities, the IEEE 802.11e still failed to meet the strict QoS support for integrated services. We believe Call Admission Control (CAC) being one of the fundamental mechanisms for QoS provisioning, if applied to IEEE 802.11e can further ensure that users get their agreed QoS with acceptable delays for data. In this report we analyze the data performance in IEEE 802.11e with a simplified version new call bounding based CAC scheme using a decomposition approximation. The Decomposition approximation provides a closed form solution if applied to integrated services such as voice and data, and thus easier to compute.

Past Publications:

B. Ongoing Research with Rashid Faruqui:

HOBm  A New Head of Burst Mechanism for 802.11e

Abstract :

802.11 commonly known as Wi-Fi is widely deployed around the globe. It is one of the most successful technologies that are implemented. Its success may be regarded due to its cost, ease and flexibility of implementation especially is non licensed ISM band. Additionally, provision of high data rates supportive of today’s high demand multimedia and broadband implementations also made it very popular. User demand to access broadband services while roaming made 802.11 as their ultimate choice. However non provision of Quality of Service (QoS) to meet stringent requirement of real time traffic in legacy 802.11 was one of the major hurdles. This led to the development of 802.11e which meet the requirement of real time traffic. This was made possible by introducing new mechanisms like Transmission Opportunity (TXOP), Block Acknowledgment (BA) and varying sizes of contention windows and interval times. Another mechanism called Head of the Burst or “Protection Mechanism” was also introduced. It is pertinent to mention here that 802.11e is still in the evolving stage, researchers have left no stone unturned to improve the standard. The aim and objectives of this thesis is two fold; one to optimize the new concepts like TXOP and BA, two to improve and enhance the Protection Mechanism. The research would be focused to meet the objectives in varying channel conditions and in contention based service only. It is anticipated that the said research would also facilitate the overall optimization of MAC protocol in 802.11e and other protocols other wireless implementations.

Past Publications:

C. Ongoing Research with Wasim Arain:

1. Impact of Load-balancing in M-TORA
Abstract :

Routing protocols in MANET are confronted with the issues of packet delivery and route latency. Both of these are important performance criteria in the performance of such protocols. We have applied a probabilistic analytical model to analyze the successful packet delivery and route latency on two protocols, DSR and M-TORA. DSR has been widely used and studied in simulations whereas M-TORA is a representative protocol with load-balancing capability hence M-TORA has been selected to study the impact of load-balancing on these parameters. In this paper we have analyzed the impact of load balancing in M-TORA and quantified the improvement in packet delivery and route latency. Simulations are suggested in the future to resolve further issues including weather the probability of route failure in M-TORA and DSR are equal.

2. An instantiation of Way Point Routing for Mobile Ad Hoc Networks


Mobile ad hoc networks are increasingly finding their existence in the marketplace heading to a new paradigm of pervasive computing. However there are many areas open to research in the field. Due to node mobility resulting in an ever-changing network topology, conventional routing methods cannot be applied in MANETS making, this is one of the core areas of research. Researchers are challenged to design protocols that can potentially scale to anything from thousand to tens of thousands of nodes and to reduce the route discovery latency. In this paper a different instantiation of Way Point Routing (WPR) model is proposed, where a route is divided into sub-routes to decrease route-latency in frequently occurring subsequent-route-discoveries and to adapt varying topologies in MANET. Simulations are suggested to be carried out in the future to evaluate the performance of the proposed routing protocol.