Toronto Networking Seminar

The Beauty and the Beast: Joint Scheduling, Routing, and Network Coding in IEEE 802.16 MeSH Networks

Matthias Hollick
Multimedia Communications Lab (KOM)
Technical University of Darmstadt, Germany

Date:  Friday, September 28,  2:10pm
Location: BA 1220 (Bahen Center)


Wireless Mesh Networks (WMNs) allow for the self-organizing formation and organical growth of wireless networks. Possible usage scenarios include public community networks, but also provider-operated wireless backbone networks. To support a rich set of applications and services, various aspects such as QOS-support, security, etc. have to be sufficiently addressed.
In this context, the use of IEEE 802.11 is well explored, however, IEEE 802.16 is a different beast. In our talk, we introduce the MeSH mode of IEEE 802.16. We first explain some missing nuts and bolts to make IEEE 802.16 MeSH mode work. We then take a network operator's perspective; here supporting QoS as well as maximizing the admitted traffic in the WMN is vital. To this end, we address the challenge of joint scheduling and QoS-aware routing. We additionally consider the deployment of network coding in the WMN under realistic assumptions derived from current state-of-the-art technology such as the IEEE 802.16 MeSH mode. Optimal solutions for the problem under study are not computationally tractable if we assume realistic problem sizes. Thus, we develop efficient heuristics that find near-optimal, QoS-aware routes while simultaneously optimizing the transmission schedule and effectively deploying network coding. To fit the target application scenario, our heuristics can trade-off the computational complexity vs. the accuracy of the solution; we are able to achieve near real-time execution while maintaining excellent solution quality. With a thorough experimental evaluation, we show the excellent performance of our heuristics in various usage scenarios.


Dr. Matthias Hollick is the head of the Mobile Networking group (MobNet) and the Ubiquitous Communications group (UbiqCom) at the Multimedia Communications Lab (KOM) of Technische Universität Darmstadt, Germany. His research interests are in the area of dependability, security, and quality of service provisioning in communication networks. In particular, the focus of his current work is on self-organizing mechanisms to enable dependable and quality-of-service-aware communication in mobile/wireless ad hoc, mesh, and sensor networks. His research has been supported by research grants from Siemens AG Corporate Technology, DoCoMo Eurolabs, and various public research bodies.
Dr. Hollick received his Diploma degree (Dipl.-Ing., M.Sc. equivalent) in electrical engineering in 1998. In 2004 he received his Doctoral degree (Dr.-Ing.) with distinction (summa cum laude) from the Technische Universität Darmstadt. Dr. Hollick is member of the ACM and IEEE and serves in various program committees and editorial boards related to his research area. He is teaching various courses in the domain of wireless/mobile communications at TU Darmstadt and at partner universities. Amongst other activities he acts as an expert for the European Union and reviewer for the German National Science Foundation (DFG). For his research, in 2005, Dr. Hollick has received Adolf-Messer Foundation award (Adolf-Messer Stiftung).