Multireceiver identity (ID) based encryption and ID-based broadcast encryption allow a sender to use the public identities of multiple receivers to encrypt messages so that only the selected receivers or a privileged set of users can decrypt the messages. It can be used for many practical applications such as digital content distribution, pay-per-view and multicast communication. For protecting...

In this paper, we construct an efficient “multi-receiver identity-based encryption scheme”. Our scheme only needs one (or none if precomputed and provided as a public parameter) pairing computation to encrypt a single message for n receivers, in contrast to the simple construction that re-encrypts a message n times using Boneh and Franklin’s identity-based encryption scheme, considered previous...

Broadcast encryption is the scheme that a sender encrypts messages for a designated group of receivers, and sends the ciphertexts by broadcast over the networks. Many research papers have done it using elliptic curve cryptography. In this paper, we propose the broadcast encryption scheme based on braid groups cryptography which is an alternative method in the public key cryptography and can red...

A b s tra c t. W e present a novel schem e o f broadcast encryption that is suitable for broadcast servers such as pay TV services. T he important feature o f our schem e is that the length o f a broadcast string in our schem e is independent o f the num ber o f receivers in the system ; hence it is suitable fo r large groups. O ur schem e is based on a trapdoor encryption technique under the R...

In this paper, we propose a semi-static secure broadcast encryption scheme with constant-sized private keys and ciphertexts. Our result improves the semi-static secure broadcast encryption scheme introduced by Gentry and Waters. Specifically, we reduce the private key and ciphertext size by half. By applying the generic transformation proposed by Gentry and Waters, our scheme also achieves adap...

Identity-based Broadcast Encryption (IBBE) has the inherent key escrow problem that Private Key Generator (PKG) can fully determine the user’s private key, which is an obstacle of the application of IBBE. The existing approaches to solving key escrow problem need the user to submit identity to multiple PKGs or interactions between PKG and the user in the private key extraction phase. For Point-...

Traitor tracing is needed because some users in broadcast encryption system may give out their decryption keys to construct pirate decoders. Many codes based traitor tracing scheme were proposed. However, as stated by Billet and Phan in ICITS 2008, they lack of revocation ability. We provide a generic scheme of codes based traitor tracing with revocation ability, based on ciphertextpolicy attri...

There is a Major problem in public clouds about the sharing of documents on attribute based policies, sharing data in a dynamic groups . With the help of advantage of low maintenance, cloud computing gives the effective solution for sharing group resource among cloud users. As the sharing of documents with different keys like attribute based encryption (ABE), and/or proxy re-encryption (PRE) ap...