Literature Review from the year 2015 in the subject Engineering - Computer Engineering, grade: 8.0, Marwadi Education Foundation (GTU), course: Computer Engineering (M.E.), language: English, abstract: In today's insecure world we are surrounded by public channels which are insecure for data transfer to each other. So it requires some type of remote user authentication mechanism to verify the legitimate user. In remote user authentication schemes, the server checks the credentials of the user and decides that the user is legitimate and genuine or not. Remote user also validates the server for mutual authentication purposes. In today's web-enabled world, two parameters are most important which are security and privacy. For that many researchers work on this field and proposed a schemes which is based on different aspects likes password table, biometric and smart card for authenticating the remote user. But these are not enough for perfect remote authentication, so a scheme is required which has stronger and accurate then old existing schemes. To make most reliable scheme, it is important to calculate computational and communication cost. Also it requires resistance against many other threats. For these mutual authentication and communication privacy are most essential requirements for remote user authentication scheme. In this survey, we analyze some papers and make survey on different aspects like types of attacks, computational cost and communication cost.