PERFORMANCE IMPACT OF MOBILITY IN AN EMULATED IP-BASED MULTIHOP RADIO ACCESS NETWORK Philipp Hofmann, Christian Bettstetter, Jeremie Wehren * , and Christian Prehofer DoCoMo Euro-Labs, Future Networking Lab, Munich, Germany lastname@docomolab-euro.com Abstract This paper investigates the performance of a multihop radio access net- work. In our testbed, nodes communicate to one access point using IEEE 802.11b and AODV routing. We measure the average packet de- lay and delivery ratio, if the node movement is emulated employing the random waypoint and random direction model, respectively. We find that random waypoint mobility yields up to 100 % better results. This shows that the testbed performance is highly sensitive to the mobility model, even if comparable mobility behavior is assumed. Keywords: Multihop radio access, routing performance, mobility modeling, testbed, ad hoc routing, AODV, random waypoint model, random direction model, network emulation. 1. Introduction The paradigm of a multihop radio access network (MRAN) is that mobile nodes serve as “wireless routers” to extend the coverage of fixed access points (see Fig. 1). This new network architecture is especially interesting for mobile communication systems in which the cell size is very small, e.g., due to operation at high frequencies. Although the design of such networks is still in the research phase, basic functionalities can already be shown today through the interworking of IP-based ad hoc networking protocols and fixed IP networks [1–6]. This paper studies the packet-level performance of a single-cell MRAN, based on measurements in a WLAN testbed with one access * Jeremie Wehren studies at the Institut Eur´ ecom, Sophia-Antipolis, France, and Ecole Poly- technique F´ ed´ erale de Lausanne (EPFL), Switzerland.