VMDFS: The Design Architecture, Model and Paging Latency

Due to the advent of wireless-networking capable mobile hand-held devices, the mobile computing paradigm is becoming a reality resulting in the creation of high-end mobile applications. The mobile applications such as, mobile multimedia and e-briefcase, require support from file systems. The existing distributed and mobile file systems are not adequately suitable to support such applications handling the challenges offered by mobile computing. In this paper, the design architecture of virtual memory based mobile distributed file system (VMDFS) is proposed based on thin-mobile-client/fat-server model. VMDFS creates the migrate-able virtual memory based mobile file system on top of the disk file systems of remote servers employing dynamic frame-lock to reduce network latency and to attain high-performance. An abstract mathematical model of VMDFS is constructed for detail analysis and verification. The Linux 2.4.22 is chosen for kernel-level implementation of VMDFS and the experimental results of network paging latencies for LAN, wireless VPN and 2.5 G GPRS are illustrated. Currently, the prototype of VMDFS is under ongoing development and testing in the industrial laboratory environment.