In mobile environment, the users communicate with each other about location based information and services with the help of network nodes. But providing security to data has become a difficult task. Currently available network security mechanisms are insufficient, but there is a greater demand for flexible, scalable security mechanisms. Mobile security is of vital importance but can’t be inbuilt. In this work, proposing two techniques for authenticating short encrypted messages that helps to preserve the confidentiality and integrity of the communicated messages. The messages to be authenticated must also be encrypted using the secure authentication codes that are more efficient than message authentication codes. The key idea in this technique is to provide the security using Encryption Algorithm. Security model should adjust with various capability requirements and security requirements of a mobile system This paper provides a survey on security in mobile systems.