Design And Implementation Of A Stateless Group Rekeying Scheme

As one of the hot topics of secure multicast communication,the main problem of group rekeying is how the GC(Group Controller)sends a new GK(Group Key)to the predefined subset on the public channel,and the revoked subset is not able to obtain the content of the message.Therefore,the focus of group rekeying is how to efficiently and securely distribute a new group key for the remaining legitimate users when there are changes in group membership(join or leave).While strict security is required for some confidential data,we argue that more and more applications,such as some resource-constrained scenarios or commercial paid video applications,are willing to sacrifice small security requirements for an efficient and extensible group rekey scheme with the development of the Internet and information technology.Although the typical CS(Complete Sub-tree)protocol has completely immune from collusion,its communication overhead is relatively high.However,ECS(Exclusive Complete Sub-tree)protocol with constant communication overhead is only secure against any single-user attack.Based on this,combining CS protocol with fully from collusion and the ECS protocol with a constant communication overhead,this paper designed and implemented TLTS-slgk(Stateless Group Rekeying Based on Two Layers of Tree Structure).Balancing the relationship between security and efficiency,the paper not only achieved a tradeoff for applications between collusion resistant and communication overhead,but also largely saved bandwidth resources.This paper first described the initialization,group rekeying and decryption of the group key in detail.At the same time,analyze the complexity of the scheme,and the relationship between the collusion attack and the bandwidth theoretically.Then,the paper implemented the program and selected different parameters for performance testing.Finally,the experiment verified that the scheme is feasible.Through the experimental results,the storage overhead,computational cost,and tunable between collusion attack and communication overhead are analyzed.