Mobile applications often get disconnected because TCP times out when a user moves from one location and reconnects at another location. This happens even with the use of Mobile IP since Mobile IP hides the IP address change from TCP but does nothing to prevent it from timing out. TCP freeze is a technique that is already part of TCP implementations and allows a receiver to stop the transmitter from sending further data when the receiver's buffers are full. In our proposed PErsistent TCP using Simple freeze (PETS) framework, we combine TCP freeze and Mobile IP to prevent TCP from disconnecting during mobile operations. No modifications of the TCP or IP protocol are needed. The required PETS module can be implemented in mobile agents which are part of the Mobile IP or in IP routers. This flexibility allows our technique to be deployed incrementally with PETS-aware hosts or PETS-aware routers intermixed with legacy hosts and legacy routers with or without Mobile IP.
Complete paper in Adobe Acrobat format.