A scalable key management scheme for secure IP multicast over DVB-S using chaos

Secure IP multicast over satellite is very important for applications such as pay per view. These applications need a key management scheme to distribute a shared group key to all group members for encrypting the data. LKH has been proposed to distribute the group key in a way that scales efficiently for large group´s size. However, the proposed schemes do not take into account the dynamicity of members. In fact, when the members of a large group are very dynamic, this leads to a massive load on the network resources and create performance deterioration, due to the high rekeying load. This paper addresses a new scalable key management scheme for encrypted multicast data by chaos. This scheme is proposed to reduce the rekeying cost and the dynamicity impact, especially on the satellite link. As a novel approach for keys transmission, we propose a new type of packet to transport a set of encrypted keys which minimizes the bandwidth consumption. The analysis of the proposed scheme shows that it can handle a very large multicast system effectively with more than tenfold reduction in the rekeying cost compared to some widely known and used protocols.