AbstractsComputer Science

The rapid progress in the technologies underlying multicast newlinenetworking has led to the development of many group oriented applications newlinesuch as pay per view online teaching, teleconferencing and communal newlinegaming In these applications group members subscribe to different data newlinestreams and members have different access privileges Security of group newlinecommunications is achieved by encrypting the messages using a group key newlinethat allows the users of that group alone to decrypt a broadcast message newlineGroup key has to be updated when there is a change with membership to newlinepreserve forward and backward secrecy As the size of the group grows newlineand or the rate of membership change increases the frequency of rekeying newlinebecomes the primary bottleneck Also in group oriented applications newlinetraditional multicast key management schemes are not sufficient to handle newlineissues associated with multiple services newlineIn multi privileged groups multiple data streams are to be newlinebroadcast to the users based on their privileges A broadcast encryption is a newlinecryptographic primitive that enables encryption of broadcast contents such newlinethat only a set of targeted users can decrypt the content In Identity Based newlineEncryption IBE users identifier information can be used as public key newlinewhich significantly reduces the need for certificates in Public Key newlineInfrastructure PKI and it poses threat to user privacy In applications like newlineMilitary field the list of receivers who receive a command should not be newlineDisclosed newline newline%%%reference p157-162.