A Framework for Automatic Reconfigurations of Protocol Stacks in Ubiquitous Computing Systems

Ubiquitous computing environment includes wireless networks, autonomic networked systems and devices with heterogeneous standards and protocols for different contexts and situations. Autonomic networked systems require mechanisms for automatic on-the-fly reconfigurations in their protocol stacks to be able to operate in different situations and contexts. Automatic reconfigurations allow the system to continue its normal operation without any need for human intervention. Since every protocol in a protocol stack has at least one peer protocol in another system, a dynamic reconfiguration of a protocol may raise the need for a reconfiguration in the peer stack. Depending on the reconfiguration type, the reconfiguration maybe carried out in a single or in both peer systems. For an assured dynamic (run-time) reconfiguration of a protocol, the execution of the protocol component is stopped in a safe state, a new protocol is initialized, and stacks switch to the new protocol at the same time. This paper proposes a protocol stack framework to support automatic and assured reconfigurations of protocol components. Our evaluation and performance measurement show the feasibility of automatic reconfigurations and an acceptable level of transparency in dynamic reconfigurations.