PRUB: A Privacy Protection Friend Recommendation System Based on User Behavior

Box 3

Matching protocol.

Client                             Client  

() Calculate

                                () Calculate

() Calculate                           () Calculate

() Produce and send a promise                         () Produce and send a promise

among which is a random                    among which is a random

sequence of                              sequence of

() Calculate and exchange the                             () Calculate and exchange the

proportion of the same attribute.                              proportion of the same attribute.