Abstract: A secure and scalable broadcast system and method of creating the same, having a plurality of nodes connected to a network with pre-positioned public/private encryption keys, including at least one root node for publishing digital messages, a plurality of interior nodes for relaying the published digital messages, and a plurality of leaf nodes for receiving the published and relayed messages. Each digital message includes an encrypted payload, and a symmetric key for decrypting the payload. The root and interior nodes publish and relay the message by encrypting the symmetric key with the public key of each node that will receive the published/relayed message from that node. Each interior and leaf node decrypts the symmetric key using its private key. Only the leaf nodes decrypt the message payload using the symmetric key. A back channel sends messages from the leaf nodes to the root nodes in the same manner.