Research On Software Clock Synchronization Algorithm For Mobile Computing Environment

In mobile computing environment, people's requirements of robustness and real-time increase gradually, and the distributed technology cannot reach the requirements at the influence of inconsistency of upper and low bandwidth and frequent disconnection of mobile network. So, it needs to find new replacing technology to achieve the requirements. Leader election problem and clock synchronization problem have always been very popular in research field of distributed computing. Research on Leader election problem and clock synchronization problem for mobile computing environment has very important theoretical significance and practical value.In mobile computing environment, leader election problem is the pre problem of clock synchronization problem. In clock synchronization system, the failure rate of the master clock server is higher than usual, which result in the decrease of clock synchronization system performance. This paper combines the leader election and clock synchronization by using leader election to solve the failure problem of master clock server in clock synchronization system.This paper studied the classical self-stabilization leader election algorithms, including the Arora-Gouda algorithm, the Dolev-Israeliz-Moranx algorithm and the IISLE algorithm. These three algorithms do not consider the stability of the network, and do not performance well in the high disconnection probability of wireless network environment. In order to solve this problem, this paper uses the idea of IISLE algorithm, combines with the mobile host disconnection probability model, improves the cycle eliminate process and puts forward a improved self-stabilizing leader election algorithm based on mobile computing environment. According to the theoretical analysis and simulation results, the improved algorithm in the election time is shorter than the Arora-Gouda algorithm and IISLE algorithm.This paper studied the instability of the mobile computing environment, and the failure rate of nodes is higher than fixed network. And, this poses a great challenge for clock synchronization. In order to solve the problem of clock synchronization in mobile networks, fault recovery mechanism must be introduced. Based on the self-stabilizing leader election in mobile computing network environment, this paper gives a failure recovery mechanism which is suit for clock synchronization problem. And, based on the failure recovery mechanism, this paper proposes a software clock synchronization algorithm in mobile computing environment. The algorithm can effectively deal with node failures in mobile network and can guarantee the global clock consistent in the network.