Broadcast encryption is conventionally formalized as broadcast encapsulation in which, instead of a ciphertext, a session key is produced, which is required to be indistinguishable from random. Such a scheme can provide public encryption functionality in combination with a symmetric encryption through the hybrid encryption paradigm. The Boneh-Gentry-Waters scheme of 2005 proposed a broadcast sc...

Broadcast encryption schemes are suitable for one-way content distribution and protection applications. In this paper, we give a concrete implementation framework for how to introduce BE schemes into Conditional Access Systems(CAS). And then we compare the transmission performance of four highly efficient broadcast encryption schemes with traditional CAS system. Based on these experimental resu...

We provide a general framework for constructing identitybased and broadcast encryption systems. In particular, we construct a general encryption system called spatial encryption from which many systems with a variety of properties follow. The ciphertext size in all these systems is independent of the number of users involved and is just three group elements. Private key size grows with the comp...

The ciphertext-policy (CP) attribute-based broadcast encryption (CP-ABBE) is a more flexible broadcast encryption (BE), in which the broadcaster encrypts the data with an access policy and a receiver set. Only receivers in the valid set who satisfy the access policy will be able to decrypt the ciphertext. However, most existing CPABBE schemes only pay attention to plaintext privacy rather than ...

Predicate encryption is a recent generalization of identitybased encryption (IBE), broadcast encryption, attribute-based encryption, and more. A natural question is whether there exist black-box constructions of predicate encryption based on generic building blocks, e.g., trapdoor permutations. Boneh et al. (FOCS 2008) recently gave a negative answer for the specific case of IBE. We show both n...

We proposed a new type of ID-based encryption scheme. Our scheme is different from other schemes on that we use tamper resistant smart card to store the private key and do the decryption job for the users. The user knows nothing about the private key. Our scheme is identical to ElGamal encryption scheme, but using RSA framework to avoid ID replacement attack. In a way, our scheme can be regarde...

Broadcast encryption is a primary technology that has been used for content protection. It enables a broadcaster to distribute content to a set of users so that only a privileged subset of users can access the content and another subset of revoked users cannot access the content. The main enabling block in a broadcast encryption scheme is the session key block, which each authorized user proces...

Broadcast encryption is the problem of a sending an encrypted message to a large user base such that the message can only be decrypted by a dynamically changing privileged subset. The study of broadcast encryption has become more and more important with the ever-increasing concern about copyright issues and the increasing interest in secure multicasting (over cable television and the Internet)....

Recently, Ren and Gu proposed a new identity-based broadcast encryption scheme, and claimed that their scheme is secure against chosen-ciphertext attack in the standard model. However, by giving a concrete attack, we indicate that Ren and Gu’s scheme is even not secure against chosen-plaintext attack. Keywordsidentity based broadcast encryption, chosen-ciphertext attack, chosen-plaintext attack...