UPS: Universal Protocol Stack for emerging wireless networks

摘要

Recent devices developed for emerging wireless networks, such as 4G cellular networks, wireless mesh networks, and mobile ad hoc networks, support multiple communication substrates and require execution of multiple protocols within a layer, which cannot be supported efficiently by traditional, layered protocol stack approaches. While cross-layer approaches can be designed to support these new requirements, the lack of modularity makes cross-layer approaches inflexible and hence difficult to adapt for future devices and protocols. Thus, there is a need for a new protocol architecture to provide universal support for cross-layer interactions between layers, while also supporting multiple communication substrates and multiple protocols within a stack. In this paper, we propose Universal Protocol Stack (UPS), which provides such support in a modular way through packet-switching, information-sharing and memory management. To show that UPS is realizable with very low overhead and that it enables concurrent and independent execution of protocols of the same stack layer, first, we present a wireless sensor network test-bed evaluation, where UPS is implemented in TinyOS and installed on individual sensor motes. Two cross-layer routing protocols are implemented and evaluated with UPS and without UPS. We also implemented UPS in the OPNET simulator, where the IP (e.g., Routing Information Protocol (RIP)) and AODV routing protocols are executed concurrently to support networks with both static and mobile wireless nodes. Our implementation shows that the overhead incurred to implement UPS is very low, and little or no modification is required to adapt existing protocols to the UPS framework. Both studies also show the advantage of enabling concurrent protocol execution within a stack layer, improving the successful packet delivery ratio or the total number of packets sent for the investigated scenarios.