Baras, Tabatabaee awarded new NSF NeTS grant

Professor John Baras (ECE/ISR) has been awarded a new National Science Foundation (NSF) Networking Technology and Systems (NeTS) grant for “Component Based Routing and Clique Based Scheduling for Modular Cross-layer Design of Mobile Ad-Hoc Networks.” The grant will provide $470,000 in funding over three years. Dr. Vahid Tabatabaee is the co-PI. Tabatabaee was co-advised by former ECE/ISR faculty member Leandros Tassiulas and Dr. Baras, and received his Ph.D. in electrical engineering in 2003. Tabatabaee is a former ISR Assistant Research Scientist, now with Broadcom Corporation in San Jose Calif.

Systematic methodologies for the design of distributed and implementable routing and scheduling algorithms that enable one to design, provision and manage mobile wireless networks with predictable and controllable performance are lacking. The research project provides a new framework for modular cross-layer design of scheduling and routing algorithms for ad-hoc networks. Efficient routing and scheduling algorithm for ad-hoc networks are among the most challenging network problems. The proposed research re-examines some of the basic assumptions of wireless network design.

Clique-based methods are used for scheduling, where cliques are defined in the interference graph. A clique based scheduler first identifies a group of critical cliques whose weights are close to the maximum to schedule. Hence, scheduling turns into finding an independent set of nodes (network links) that cover the cliques. Clique based policies are developed to achieve optimal throughput and as basis for distributed implementable algorithms for scheduling. Clique based scheduling is easier and more flexible because to schedule a clique we can schedule any link of it, and when a link is scheduled all cliques that it belongs to are scheduled. It also provides a pathway to extend Network Calculus results, to provide deterministic performance bounds for wireless networks.

For the routing, a component-based design model is used that divides the routing protocol into components with separate design concerns. Stability, agility and flexibility are better achieved through a component-based architecture. These solutions are still cross-layer, but they have well defined interfaces for signaling, control and information exchange between components and layers. Performance models provide a systematic methodology to study and quantify the relationship and sensitivity of the network performance to its components’ parameters. Performance models provide a traceability mechanism that connects the network requirements to the components and architecture design abstractions, and lead to the development of an effective and modular design methodology for networks. Cross-layer clique based congestion metrics provide a promising and exciting venue to research and develop novel traffic engineering algorithms for wireless networks.

The research will yield new principles and fundamental methodologies for the design, performance evaluation, and control of multi-hop wireless networks. The methodologies can be used to estimate the capacity region of wireless networks. The project will produce multi-criteria optimization algorithms, and algorithms for sensitivity computations. The component based design model of the project has applications to other areas of networking like transportation, vehicular and infrastructure networks.

Published October 4, 2010