The Transport Layer Revisited

End-to-end transport protocols such as TCP perform poorly in mobile environments, primarily due to their inability to cope with the dynamics incurred by node mobility. We re-consider the design decisions that lead to the end-to-end design of the transport layer. To this end, we present a framework for reliable hop-by-hop transport protocols. Based on this framework, we design and evaluate such a protocol and compare its performance to TCP. Overall, our hop-by-hop protocol achieves up to 3 times faster delivery of messages in our experiments with mobile networks. We conclude that hop-by-hop protocols might be more suitable for reliable communication in mobile networks than end-to-end protocols.