Protection of sensitive data is an important issue, precisely during transmission over internet. Efficient cryptographic methods are there to protect data but everything depends on the protection of the encryption key. Threshold cryptography enables the construction of reliable and robust key management system which can reconstruct the key even in the destroy of some shares and on the contrary the key cannot be reconstructed unless a predefined set of shares are been accumulated. The earlier schemes available in literature lead to high computational complexity during both sharing and reconstructing. Here we are suggesting a scheme which employs simple graphical masking method, done by simple ANDing for share generation and reconstruction can be done by simple ORing the qualified set of shares. We are proposing to append secret sharing technique along with conventional cryptography technique for key management to make key management more robust mainly against the chance of compromise and single point failure. Nevertheless it confirms authenticity, confidentiality, non-repudiation and integrity as well.

Shared cryptography Key management Message digest RSA Crypto system