Advanced Split-TCP with End-to-End Protocol Semantics over Wireless Networks

The worldwide mobile traffic is growing rapidly and more than 90% of the internet traffic relies on the Transmission Control Protocol (TCP) protocol, which is known to have a poor performance over unreliable wireless networks. One of the promising TCP enhancement mechanisms that are being considered by the wireless network operators is the Split-TCP. It is also quite well known that the Split-TCP suffers from broken end-to-end protocol semantics, and this may be a significant drawback in some scenarios, where large file transmissions may get aborted after consuming a large volume of network resources. There are various enhancements to overcome this pitfall, but at the expense of a loss in performance. In this paper, we propose a novel Advanced Split-TCP (AS-TCP) mechanism, designed with the goal to improve significantly the application throughput while maintaining the end-to-end protocol semantics down to the byte level, as through the conventional TCP. Our findings indicate that the TCP throughput gains achieved through AS-TCP with respect to a conventional TCP may be above 60% over a 4G LTE network. Furthermore, AS-TCP may enable TCP throughput gains in excess of 200% for some network and traffic conditions. The throughput gains are expected to be even greater when advanced radio technologies are deployed. Hence, we anticipate that AS-TCP will enable the Split-TCP mechanism to be widely deployed in both current and next generation networks, such as 5G.