US Patent 8132005 Establishment of a trusted relationship between unknown communication parties

The present invention provides an establishment of a trusted relationship between two mutually unknown communication parties in a communication system without the use of a trusted third party. The invention is based on non-interactive proofs-of-work being purpose-bound for establishing the trusted relationship and cryptographically signing information to be transferred between the communication parties using such proofs-of-work for the solving of a problem instance along with verifying the proofs-of-work and generating a session object for a trusted relationship, when the verifying yields an affirmative result.