Clock Synchronization in Wireless Sensor Network

Wireless sensor networks have tremendous advantages in monitoring environment, civilian, military, health, home, education and scientific, it requires degree of synchronization to best results. The operation confirming that the processors spread over a wide area possess a standard time is synchronization of clock. At each sensor node their local clocks are synchronized to a common time. Its main applications are communication, security, industry. The focus on wireless sensor network is due to extensive application. There are many difficulties in building and designing sensor network and is a challenge of providing clock synchronization. It is very important that the application in wireless sensor network choose a   correct clock synchronization method. This article illustrate the existing clock synchronization approaches in wireless sensor network and estimates the clock skew and clock offset in synchronization protocol.