A broadcast encryption scheme with personalized messages (BEPM) is a scheme in which a broadcaster transmits not only encrypted broadcast messages to a subset of recipients but also encrypted personalized messages to each user individually. Several broadcast encryption (BE) schemes allow a broadcaster encrypts a message for a subset S of recipients with public keys and any user in S can decrypt...

Besides traditional functionality of broadcast encryption, attribute based broadcast encryption (ABBE) provides more flexible assess control mechanism over encrypted data. In this paper, a ciphertext-policy ABBE (CPABBE) scheme is proposed. In such scheme, user’s private key is attached with attributes and an index while ciphertext is associated with an access structure and a broadcast set. A k...

This paper puts forward new efficient constructions for public-key broadcast encryption that simultaneously enjoy the following properties: receivers are stateless; encryption is collusion-secure for arbitrarily large collusions of users and security is tight in the standard model; new users can join dynamically i.e. without modification of user decryption keys nor ciphertext size and little or...

A broadcast encryption system allows a center to communicate securely over a broadcast channel with selected sets of users. Each time the set of privileged users changes, the center enacts a protocol to establish a new broadcast key that only the privileged users can obtain, and subsequent transmissions by the center are encrypted using the new broadcast key. We study the inherent trade-off bet...

In broadcast encryption schemes, a distribution center broadcasts an encrypted message to a subset S chosen from a universe of receivers and only the intended users are able to decrypt the message. Most broadcast encryption schemes do not provide anonymity and the identities of target receivers are sent in plaintext. However, in several applications, the authorized users’ identities has the sam...

A forward-secure encryption scheme protects secret keys from exposure by evolving the keys with time. Forward security has several unique requirements in hierarchical identity-based encryption (HIBE) scheme: (1) users join dynamically; (2) encryption is joining-time-oblivious; (3) users evolve secret keys autonomously. We define and construct a scalable pairing-based forward-secure HIBE (fsHIBE...

A broadcast encryption system generally involves three kinds of entities: the group manager that deals with the membership, the encryptor that encrypts the data to the registered users according to a specific policy (the target set), and the users that decrypt the data if they are authorized by the policy. Public-key broadcast encryption can be seen as removing this special role of encryptor, b...

We propose a new broadcast encryption scheme π based on the idea of ‘one key per each punctured interval’. Let N and r be the numbers of total users and revoked users, respectively. In our scheme with p-punctured c-intervals, the transmission overhead is asymptotically r p+1 as r grows. We also introduce two variants of our scheme to improve the efficiency for small r. Our scheme is very flexib...