One of the major issues in video data transmission over internet is the time involved in sending and receiving huge amount of data. The video data should be compressed to aid faster transmission over the network. Security is another important concern during video transmission. Heavyweight and lightweight encryption algorithms are used for secured video transfer over the internet. Heavyweight encryption algorithms are not adopted for mobile devices in wireless networks because encryption process takes more time. Lightweight encryption algorithms are employed in hand held devices, low power operating systems and low power wireless sensor networks because they take less time for encrypting video data [1]. In this paper, a Fast Random Bit Encryption method for encrypting video data is proposed. It is a lightweight encryption algorithm which takes video data from a compressed domain. The proposed algorithm takes very less time for encryption and it gives more security than all other existing algorithms. As the proposed solution employs multi-level encryption along with key encryption, the attacker cannot easily break this algorithm. In this paper, we have also done a comparative study of existing lightweight algorithms with heavyweight algorithms like AES and RSA. Our analysis shows that lightweight algorithms take less time than existing heavyweight algorithms. © EuroJournals Publishing, Inc. 2011.