Using Shamir＇s secret sharing scheme to indi- rectly share the identity-based private key in the form of a pairing group element, we propose an efficient identity-based threshold decryption scheme from pairings and p...Using Shamir＇s secret sharing scheme to indi- rectly share the identity-based private key in the form of a pairing group element, we propose an efficient identity-based threshold decryption scheme from pairings and prove its se- curity in the random oracle model. This new paring-based scheme features a few improvements compared with other schemes in the literature. The two most noticeable features are its efficiency, by drastically reducing the number of pair- ing computations, and the ability it gives the user to share the identity-based private key without requiring any access to a private key generator. With the ability it gives the user to share the identity-based private key, our ID-based threshold decryption （IBTD） scheme, the second of its kind, is signif- icantly more efficient than the first scheme, which was de- veloped by Baek and Zheng, at the expense of a slightly in- creased ciphertext length. In fact, our IBTD scheme tries to use as few bilinear pairings as possible, especially without depending on the suite of Baek-Zheng secret sharing tools based on pairings.展开更多
文摘Using Shamir＇s secret sharing scheme to indi- rectly share the identity-based private key in the form of a pairing group element, we propose an efficient identity-based threshold decryption scheme from pairings and prove its se- curity in the random oracle model. This new paring-based scheme features a few improvements compared with other schemes in the literature. The two most noticeable features are its efficiency, by drastically reducing the number of pair- ing computations, and the ability it gives the user to share the identity-based private key without requiring any access to a private key generator. With the ability it gives the user to share the identity-based private key, our ID-based threshold decryption （IBTD） scheme, the second of its kind, is signif- icantly more efficient than the first scheme, which was de- veloped by Baek and Zheng, at the expense of a slightly in- creased ciphertext length. In fact, our IBTD scheme tries to use as few bilinear pairings as possible, especially without depending on the suite of Baek-Zheng secret sharing tools based on pairings.
