Resolving TCP re-ordering issues on a multi-homed NEMO-based network

Abstract

A multi-homed Network Mobility (NEMO) architecture has been proposed previously to improve the reliability and aggregate the bandwidth of Mobile Router (MR) by simultaneously using multiple wireless links. In this paper, we discuss some potential issues that could affect the performance of TCP traffic in a multi-homed architecture. In addition, we propose a protocol to improve the performance of sending a single TCP connection over multiple wireless links on a MR. Our protocol consists of three components. First, we use a reordering buffer to eliminate unnecessary retransmission caused by out-of-order packets. Second, we develop a Multi-homed Split Connection mechanism to enable the TCP connection to quickly adapt to the conditions of multiple links when packet loss occurs. Finally, a Scheduled Window-based Transmission Control algorithm is proposed to mitigate the negative effects of out-of-order packets in the case of using heterogeneous links in a multi-homed environment. We evaluate the performance of our protocol by comparing it with the Concurrent Multi-path Transfer SCTP (CMT-SCTP) and show that it can resolve several performance issues.