Mobility-Aware Application Protocols

Temporal/spatial disruptions and IP changing caused by host mobility lead the user applications to fail. This remains a problem due to the ossification of the TCP/IP protocol stack and the lack of support of existing solutions in enabling connection failure tolerance at application layer. To preserve integrity and transmission consistency upon erroneous communication events caused by host mobility, enabling mobility awareness is a key requirement for the current user applications. In this paper, we provide a comprehensive study on mobility-aware application protocols that ensure reliability and resiliency for long-lived TCP sessions established between clients and severs that migrate across different wireless IP networks on the Internet. To this end, we modeled and simulated such protocols through general-purpose state machines, which we conceived regarding the Socket semantic to resume session from broken connections. Simulations results revealed how internal and external factors, i.e., protocol design decisions and mobile environment conditions, respectively, can and cannot influence performance. When comparing results with TCP-Migrate - a well-known transport layer mobility protocol, handover delays in application protocols are longer in single jumps between mobile client and stationary server, but shorter in double jumps, when both client and server are mobile entities.