Network is one of the rapid growing technology in Today's world. Network is attached in our life from small things to large things. Everywhere network is spreaded. where people are surrounded by network. We can get more advantage in various fields by using the network. But at the same time there is a lot of things is there to attack the security of the network. In this paper we discuss about the main common attacks in the network, about the causes of the attack and how to recover from that. So this will be helpful for the researcher to come up with the best prevention of the attacks in network.