Secure distributed batch rekeying algorithm for dynamic group

Security and efficiency of rekeying are crucial requirements for secure communication in dynamic groups. Aiming at the drawbacks of traditional distributed batch rekeying algorithms, which are a waste of resources and vulnerable to collusions attack, DBRM marking algorithm is designed, which creates a subtree consisting of joining members. Based on DBRM algorithm, a secure batch rekeying algorithm named SDBR is proposed. SDBR is resistant to collusions attack by changing the blinded keys known to the leaving members and it can also avoid a renewed node to be rekeyed more than once. Mathematical models of communication cost and computation cost are presented by theoretical analysis, and the performance of SDBR algorithm is validated by simulation experiment. Analysis results show SDBR is an algorithm suitable for large dynamic collaborative group.