Characterizing 4G and 3G Networks: Supporting Mobility with Multi-Path TCP

Advances in cellular technology have increased the demand of accessing the Internet dramatically. Cellular technology not only enables mobility, but also allows redundant connectivity using multiple wireless paths to improve availability, reliability, and performance. Multiple paths enable the potential to shift traffic from broken or congested paths to higher-quality ones as traffic characteristics dynamically change, particularly during movement. However, little work has been done to date studying cellular networks or their suitability. This paper characterizes the behavior of cellular networks, examining 3G, 4G, and Wi-Fi networks for both single-path and multi-path data transport. Our contribution is two-fold: First, we perform measurements of single path transport using TCP over major US cellular wireless networks (both 4G and 3G), and characterize them in terms of throughput, packet loss, and round-trip time. Second, we measure and evaluate transport using multi-path TCP in cellular environments and show that leveraging path diversity under changing environments is a promising solution for more reliable and efficient TCP transfer. We also identify potential issues in using multi-path TCP which can limit performance.