Sensitive and confidential information is vulnerable to various kinds of misuse when data contained in, or transmitted to / from computer systems they may exposed to passive and / or active threats . Consequently, mechanisms must be provided for the protection of unauthorized access, undetected deletion, modification or insertion of the false information. To meet these requirements cryptographic techniques, must be employed which include, encryption algorithms, that encipher the message (plain text), into unintelligible cipher text, using ciphering key. Decryption algorithm is an inverse...

Considerable effort has been put towards developing intelligent and natural interfaces between users and computer systems. This is done by means of a variety of modes of information (visual, audio, pen, etc.) either used individually or in combination. The use of gestures as means to convey information is an important part of human communication. The automatic recognition of gestures enriches Human-Computer Interaction by offering a natural and intuitive method of data input.