A Novel Mechanism for Data Streaming Across Multiple IP Links for Improving Throughput and Reliability in Mobile Environments

With ubiquitous computing and network access now a reality, multiple network conduits will be available to mobile as well as static hosts (for instance, wired connections, 802.11 style LANs, Bluetooth, cellular phone modems, etc). Selection of the preferred mode of data transfer is a dynamic optimization problem depending on the type of application, its bandwidth/latency/jitter requirements, current network status such as congestion or traffic patterns, cost, power consumption, battery life, and so on. Furthermore, since wireless bandwidth is likely to remain a scarce resource, we foresee scenarios wherein mobile hosts will require simultaneous data transfer across multiple IP interfaces to obtain higher overall bandwidth. We present a brief overview of related work identifying schemes that might be applicable to the problem, along with their feasibility, and pros and cons. We then propose a new mechanism to aggregate the bandwidth of multiple IP links by splitting a data flow across multiple network interfaces at the IP level. Our method is transparent to transport (TCP/UDP) and higher layers. We have analyzed the performance characteristics of the aggregation scheme and demonstrated significant gain when the links being aggregated have similar bandwidth and latency. The use of multiple interfaces also enhances reliability. Our analysis identifies the conditions under which the proposed scheme, or any other scheme that stripes a single TCP connection across multiple IP links, can be used to enhance throughput. Several interesting directions for future work have also been identified.