A Session-Based Mobile Socket Layer for Disruption Tolerance on the Internet

Several existing IP mobility solutions use invasive approaches, when adjustments in legacy protocols from the TCP/IP stack are necessary, or rely on specific network infrastructures. We devised an architecture to handle mobility using a Session-based Mobile Socket Layer (SMSL). With no need for software adaptation in the core of the network or adjustment on the TCP/IP stack, SMSL operates only at the end systems involved in the communication, being fully transparent to neighboring Transport and Application layers. The session scheme allows mobility awareness for TCP-based applications that require resilience to failures, delays, or disconnection. A general-purpose API extended from the Socket and implemented in GNU/Linux provides session services, such as tracking mobile peers, detecting disruptions, and suspending and resuming sessions with efficiency, security, and reliability. In this paper, we present the entire session support system as a mature work of research achieved with advances made in our previous study. The results of experiments in real and emulated test environments demonstrate efficiency. SMSL introduces little overhead, with a mean goodput degradation of 6.9% compared to an application implemented on top of the standard TCP/IP stack. Disruptions are detected in microseconds and suspended sessions resume in milliseconds for single-homed mobile nodes.