A Key Based Secure Threshold Cryptography for Secret Image

10.6633/IJNS.201601.18(1).07

Prabir Kr. Naskar；Hari Narayan Khan；Atal Chaudhuri

Compression ； image Sharing ； key-based threshold cryptography ； perfect secret sharing (PSS) ； random selection of secret bytes ； statistical analysis

International Journal of Network Security

18卷1期（2016 / 01 / 01）

68 - 81

英文

This paper presents a key based secured (k, n) threshold cryptography where key is used to encrypt the secret and then the secret as well as key is shared among set of n participants. In sharing phase, each secret byte is selected randomly from secret fields depending upon the key. That provides additional protection of the secret data. Also, each share has some bytes missing and these missing bytes can be recovered from a set of exactly k shares. Thus a given byte position can be confirmed for any k shares, but not less than k. Hence k shares are required to give back the secret. As a result, the generated shares are compressed and if k is closer to n then the compression ratio is increased. That provides strong protection of secret data. At the reconstruction phase only when a qualified set of legitimate shares comes together then reconstruction is possible. The proposed scheme is described in detail along with its security analysis, such as key sensitivity analysis and statistical analysis. This scheme has been tested using different images to prove that the scheme has great potential and has a good ability to achieve the confidential security.