First Unicast Communication Network Protecting both Content and Metadata

The present paper deals with the first known unicast communication system per Sealed Cloud, protecting not only content but also metadata privacy, i.e. who communicates with whom, when, how much. To date, this was only feasible with highly inefficient, asymmetrically encrypted broadcast-and-select methods. To prevent spying, most systems rely on cryptography, so only the sender and receiver can decrypt the exchanged data. However, unicast systems still require disclosure of a receiving address to the routing entities. Such metadata reveals much of the communicating parties' intentions and is fairly easy to analyze, making full protection of communications between citizens, businesses and public organizations imperative. The well-established Sealed Cloud system technically prevents access to all data during processing. In theory, provider staff is able to deduct metadata from traffic volume and time correlations. However, fully provider-proof, sealed communication is ensured by de-correlation of encrypted traffic into and out of the Sealed Cloud.