Low-latency wireless video over 802.11 networks using path diversity

Wireless local area networks, such as 802.11b, are becoming wide-spread as they provide simple wireless connectivity and data delivery. This paper examines low-latency (conversational) video communication over 802.11b networks. The challenges to enable low-latency video include overcoming the highly variable delays, losses, and bandwidth of 802.11b wireless networks. To overcome these challenges we (1) employ the H.264/MPEG-4 advanced video coding (AVC) standard for high video compression efficiency and good resilience to losses, (2) use low-latency best-effort transport mechanisms, and (3) exploit the potential path diversity between each mobile client and multiple access points in the infrastructure, where we use multiple paths simultaneously or switch between multiple paths (site selection) as a function of channel characteristics. Our results indicate that the proposed system can provide significant benefits over conventional single access point (single path) systems.