Clean Slate Mesh Protocol Design Using WARP An AutoRate MAC Protocol Demo Joseph Camp, Ahmed Khattab, Chris Hunter, Patrick Murphy, Ashu Sabharwal, and Ed Knightly Rice University Electrical And Computer Engineering

Clean Slate Mesh Protocol Design w/ WARP High-performance Custom Hardware PHY in FPGA logic (HDL) MAC embedded in PowerPC (C++) Platform Support Packages Open-Access Repository Research Applications Novel MAC/PHY Algorithms Strong Interaction Across Layers WARP is a fully custom hardware platform used to implement protocols at the PHY and MAC layers. With such a platform, we can and have implemented PHY layer protocols in the FPGA logic for parallelization of Automatic Gain Control, Packet Detection, various modulation schemes, MIMO and more. We can and have implemented MAC layer protocols using the PowerPC with embedded C for such things as random access, scheduled access, rate adaptation, and more. WARP is a Rice platform but is available to the research community at-large as an Open-Access Research Platform. 1 - Virtex II FPGA/PowerPC 2 - 2.4/5 GHz Radio Boards 3 - Ethernet Interface

Example: An Autorate MAC Protocol Demo Various AutoRate Fallback (ARF) in IEEE 802.11 device ARF with Adaptive RTS (RRAA) Off-the-shelf devices prevent experimentation of such autorate protocols -- only measured in simulation Receiver Based AutoRate (RBAR) Opportunistic AutoRate (OAR) Protocols switch in real-time (push of a button) In this demo, we will stream video from one laptop, to a WARP board, over the wireless medium, to another WARP board, to a connected laptop which will display the video. To make this more interesting, we are able to change MAC protocols at the push of a button from various AutoRate mechanisms that we have implemented on the board with uninterrupted video. In almost all 802.11 devices, some form of AutoRate Fallback is used. However, we have implemented SNR-based protocols such as Receiver-Based AutoRate and Opportunistic AutoRate which do not use losses to determine the physical rate but rather the SNR at the receiver. Through extensive measurements and scenarios we will determine how these protocols perform across environments including real and emulated channels.