Abstract: Systems, methods and devices for distributing a group key between a transmitter and a group of receivers connected over a network. The described group key distribution can be implemented in any television network for encrypted transmission of television related content to large and dynamic groups of subscribers' receivers. Wherein each receiver contributes to the group key by securely transmitting its contribution to the transmitter. The transmitter also contributes to the group key and generates the group key based on all contributions. The transmitter further generates partial keys specific to each receiver such that each receiver can generate a copy of the group key from its contribution and the partial key it receives. The transmitter sends each receiver its corresponding partial key so that each receiver can calculate a copy of the group key.