The global positioning system (GPS) is a constellation of satellites that broadcasts signals, which are used to derive precise timing, location, and velocity information. The derived information can then be clubbed with other systems, such as communication devices, computers, and software to perform a variety of functions. With equipments ranging from hand-held receivers to rack-mounted electronics, the signals of global positioning systems can be used by anyone, anytime, anywhere in the world. GPS provides an efficient method of tracking position of objects anywhere on earth and in space. The use of GPS synchronization in protection, control and monitoring systems is becoming more popular in the field of power systems. GPS receiver receives the signal from artificial satellites orbiting around the earth and calculates its position by using data from at least 3 satellites by using triangulation algorithm. However, more recently, the adoption of SDH (Synchronous Digital Hierarchy) as the international standard for high speed data communication over optical fiber and microwave has given rise to communications links with characteristics which are unsuitable for traditional numerical line current differential relays. GPS (Global Positioning System) synchronization is applicable for use over SDH communication networks.