Hardware security platform for multicast communications

Secure multicast applications of multimedia contents, such as Internet TV, pay per view, satellite TV, etc., need to maintain a high number of keys. In these applications, a user contracts a group of channels or even specific content (films, sports, etc.) which do not have to coincide with the services contracted by other users, so different keys are needed to encrypt the contents. These keys must be recalculated, encrypted and redistributed when a user joins or unjoins a specific group in order to prevent users who do not belong to a group from being able to access the contents. Original algorithms generate only one group key for all users, so this key must be recalculated and resent when a user joins or unjoins in the user group. This is an important problem, because a group key could be changed even when one content is performing. This paper presents a high performance implementation of one of the most employed algorithms of group key maintenance, the LKH algorithm, using reconfigurable hardware and a very high and realistic number of users (8,388,609). The performance obtained by this study improves a lot other results found in the literature in terms of both performance and number of users.