Fair Secure Computation with Reputation Assumptions in the Mobile Social Networks

Box 1

The description of functionality ShareGen in the fail-stop setting.

Functionality ShareGen

(1) Inputs: ShareGen takes as input a value (resp. ) form (resp. ).

 If either input is of no vail, then ShareGen returns to both parties.

(2) Computation: It includes the following steps:

(a) Choose a value such that ( is a constant and is the threshold of Shamir's

 secret sharing scheme), so (see Lemma 3).

(b) Generate two shares , of such that .

(c) Randomly select two degree polynomials and , where and .

(3) Outputs: ShareGen sends to and to , where .