Multi-Authority Ciphertext-Policy Attribute Based Encryption With Accountability
This addresses fine-grained access control problems for systems requiring user traceability and collusion resistance, though it appears incremental.
The paper tackles security issues in single-authority attribute-based encryption by proposing a multi-authority scheme with policy hiding and accountability, proving it secure under selective-set IND-CPA.
Attribute-based encryption (ABE) is a promising tool for implementing fine-grained access control.To solve the matters of security in single authority, access policy public, not traceable of malicious user,we proposed a scheme of multi-authority. Moreover, multi-authority may bring about the collusion of different authorities.In order to solve these problem,we proposed a scheme of access tree structure with policy hidden and access complex.Once the private key is leaked, our scheme can extract the user ID and find it.If the authorities share their information with each other,the scheme avoid them to combine together to compute the key information and decrypt the ciphertext.Finally,the scheme proved to be secure under selective-set of IND-CPA.