General Information
NameDr. Yehuda Ben-Shimol
DepartmentDepartment of Communication Systems Engineering
Emailbenshimo@bgu.ac.il
Academic RankSenior lecturer
FunctionB.Sc committee - chairman, Department of Communication Systems Engineering


Education

 
  • 1982-1986: B. Sc. at the department of Electrical and Computer Engineering, Ben Gurion University, Israel. Specializing in control theory, electronic equipment, signal processing and communication systems.

 

  • 1987-1990: M.Sc. at the department of Electrical and Computer Engineering, Ben Gurion University, Israel.

Research in image and signal processing. (Cum Laude)

Thesis title: “Calculation of motion features of beating cilia from an image sequence sampled in real time”

Advisors: Prof. Izak Dinstein, Prof. Zvi Priel and Prof. Amnon Meizelse

  • 1992-1996: Ph.D. studies at the department of Electrical and Computer Engineering, Ben Gurion University, Israel.

Research in relativistic electrodynamics (Summa Cum Laude).

Dissertation title: “Relativistic electrodynamics in the presence of moving media and scatterers”.

Advisor: Prof. Dan Censor.

 

  • 1997-1998: Post Doc. at the faculty of Electrical Engineering, Technion, Israel. Research in the area of communication networks.

Host: Prof. Moshe Sidi.

   

Research Interests

 Communication networks researching various topics in this arena, covering issues from graph theory, communication protocols, queueing theory and models of wireless radio channels of different environmental conditions.
   

Research Projects

 

The following list summarizes my research activities during the last 4 years:

  • Modeling wireless communication channels in urban, sub-urban, rural and in-house environments (scientific publications [6, 9, 10] and conferences [14]). These days we combine of grade of service requirements (GoS) with link budget properties for various environments.
  • Billing and Pricing models in IP networks (see scientific publications [11], conferences [11] another paper was submitted). This is still an on going research issue where we try to model and integrate the user behavior into the theory and mechanisms of billing and pricing in IP networks.
  • Network anonymity in the Internet (see scientific publications [8], conferences [12], another paper was submitted). Anonymity is an important research issue in overlay networks in general and of important practical implications on current and near future networks. In these researches we solved the problem of the immediate eavesdropper by using multiple ISPs. We focused both on wired and wireless networks, developed the anonymity level that is reached by our solution and tested the generated delay with extensive network simulations.
  • Novel multicasting protocol for wireless ad hoc networks using unique graph layout properties. In this research we developed a novel approach for the construction of a multicast tree which balances between the properties of shortest path trees and minimal cost trees of the underlying graph. A distributed protocol was developed in several stages. The final version of the protocol solves various malicious scenarios that are relevant to wireless ad hoc scenarios.  A paper was submitted for publication in WCMC journal.
  • Novel MAC protocols for wireless ad hoc networks. This is an on going research were we try to develop efficient solutions to the problem of hidden terminals under requirements of quality of service (QoS). We integrate ideas from chaotic dynamical systems (a novel approach) to control and minimize the resolution time of the protocol. The research is expected to be finished until the end of the summer (September 2004).
  • Scheduling algorithms for OFDM and OFDMA fixed access wireless networks. In this research we deal with the problem of two-dimensional resource allocation (slotted time and multiple sub-channels). We already defined in detail the problem, its constraints and developed few heuristic solutions. The solution deal with conditions such as minimal and maximal transmission time bounds, power limitations, fairness, etc.  This research will expected to mature to a submitted journal paper in few months.
  •  “Performance evaluation of a queue with geometrical server and non-Markovian input traffic”. In this research we develop theoretical state equations which enable us to predict various properties (queue occupancy, sojourn time and distribution of the inter-arrival times of the departure process). This research is expected to be finished until October 2004.
  • “Adaptive fault tolerant self-adjusting protocol for half-duplex mobile data network”. This research is in the initial phase of problem definitions and literature survey.
  • A new research issue that I deal with is the so called “New Kind of Science” published recently by Stephen Wolfram. I’m in a process of extensive research that try to generate complex behaved traffic patterns from simple rules applied on three-regular or non-symmetrical or small-world network graphs. The results reached so far suggest that part of the complex behavior that is observed in communication networks are caused by network topology - in contrast to the common opinion that this is caused only by combination of user behavior and properties of network protocols (especially in the transport layer).
  • Automatic design of resources for an optical switch for near future optical networks combines the methodologies of genetic programming and NKS (mentioned above). This work is supported in part by the office of the chief scientist (DyFON magneton).
   

Research Abstract