Abstract -Signcryption is a cryptographic primitive that fulfills both the functions of digital signature and public key encryption simultaneously in low cost compare with the traditional signature-then-encryption approach. In this paper, we propose a new method for providing more secure key generation against the outer and insider attack, which is based on the mouse movements. Tag KEM process is implemented using this True random number generator (TRNG) and it generates most secure and nondeterministic secret keys for data encryption which held in the Data encapsulation mechanism (DEM). We compare the statistical reports of the proposed system with the previous methods which is used to implements TKEM based on pseudo random number generators, and it works better in manner of security
