Haddock-FS A Distributed File System for Mobile Ad-hoc Networks

The emergence of more powerful and resourceful mobile devices, as well as new wireless communication technologies, is turning the concept of ad-hoc networking into a viable and promising possibility for ubiquitous information sharing. However, the inherent characteristics of ad-hoc networks bring up new challenges for which most conventional systems don’t provide an appropriate response. Namely, the potential lack of a pre-existing infrastructure, the high topological dynamism of these networks, the relatively low bandwidth of wireless links, as well as the limited storage and energy resources of mobile devices are issues that strongly affect the efficiency of any distributed system intended to provide ubiquitous information sharing. This dissertation describes Haddock-FS, a transparent replicated file system designed to support collaboration in the novel usage scenarios enabled by mobile adhoc environments. Haddock-FS is based on a highly available optimistic consistency protocol. In order to support co-present collaborative activities in mobile ad-hoc environments, it provides stronger consistency guarantees during operation within highly connected ad-hoc groups of mobile devices. Moreover, Haddock-FS is based on a cross-file, cross-version content similarity exploitation mechanism and employs a bounded log truncation scheme so as to effectively cope with the network bandwidth and device memory constraints of these environments.