Clock synchronization for mobile ad hoc networks

Abstract

As mobile networking advances, there is a need for services such as clock synchronization that improve performance and support the development of higher-level applications. This can be achieved by adapting existing algorithms (such as the Network Time Protocol) used in wired networks (e.g. Internet) to Mobile Ad Hoc Networks (MANets). It may also be achieved by developing other algorithms that achieve clock synchronization and may be suitable for MANets. Using the Network Time Protocol (NTP) as a basis, an algorithm was developed for clock synchronization in Mobile Ad Hoc Networks. NTP is the Internet standard for clock synchronization and has been designed for wired networks. Since mobile ad hoc networks are inherently different from wired networks, which are static, several components of NTP were analyzed and modified in developing the algorithm for MANets. Simulations were performed for testing a basic version of the algorithm using Network Simulator 2, a discrete event simulator widely used in research for simulating mobile ad hoc networks. Simulation results reveal interesting information about how the tested algorithm performed. Possible ways to improve the algorithm are also discussed. Another approach to achieve clock synchronization uses MANet specific communication primitives with Minimum Connected Dominating Set (MCDS) approximation algorithms. This involves using a subset of nodes in the network to broadcast clock information to neighboring nodes. Several MCDS approximation algorithms have been developed and it is important to analyze their strengths to determine how suitable they are for clock synchronization in mobile ad hoc networks. A few such algorithms are discussed. This work may encourage further research in improving the proposed algorithm or in the development of NTP based clock synchronization algorithms. Finally, it may contribute to the implementation and advancement of clock synchronization in mobile ad hoc networks.