Using Multiple Links Simultaneously to Increase Capacity for Multi-homed Terminals in Heterogeneous Wireless Networks

Aggregating fractional bandwidth from multiple links in heterogeneous wireless networks can provide an opportunity for network providers to scale up capacity for multi-homed terminals. Multi-homed terminals come equipped with multiple interfaces, which can be used to transmit and receive data over multiple paths simultaneously. This can improve performance in terms of increased throughput, short delays, and loss resilience. However, parallel transmission over heterogeneous links can lead to problems, such as packet reordering. Packet reordering occurs when packets of the same stream arrive at the receiver out of the required order. Transmission Control Protocol (TCP) misinterprets packet reordering as congestion loss and reacts by shrinking the congestion window and launching spurious fast retransmit. Consequently, the application throughput can drop dramatically. Packet reordering can also induce additional delays, which can degrade performance of delay-sensitive applications. In this paper, we present a new multipath packet transmission solution that addresses packet reordering while ensuring that delay-sensitive packets are delivered to meet their deadlines. The proposed solution is evaluated in the ns-3 simulation environment. The simulation results reveal that our solution reduces packet reordering while improving throughput performance.