TLQAP: A topology and link quality assessment protocol for efficient node allocation on wireless testbeds

Abstract

In this paper we present Topology and Link Quality Assessment Protocol (TLQAP), which we have implemented as a wireless testbed management framework component, that is used to inspect link quality between wireless testbed nodes and appropriately map them to user experiment requirements. TLQAP is mainly an OSI layer 2 design for fixed location, non RF-isolated wireless testbed deployments, which assesses interconnection topology and link quality by estimating packet delivery ratio (PDR) and transmission delay at each node for all requested channel, rate and transmission power combinations. Moreover, TLQAP builds a measurement history log and creates a channel utilization profile, in the context of each testbed node, for all the nearby testbed-external devices that operate independently in the region and are not under the management framework control. The analysis of this information enables TLQAP to choose the channels that have the highest probability of being free during an experiment. TLQAP OSI layer 2 component has been implemented in the click modular router framework and the controller component has been integrated with OMF management framework for wireless testbeds. To outline TLQAP benefits, we have performed experiments on our ORBIT node testbed and we compare it to an existing application level measuring tool. Copyright 2009 ACM.