Research Article

Privacy Protection of Social Networks Based on Classified Attribute Encryption

Algorithm 3

Permission replacement algorithm.
Input: the user i, the new private key
(1)if (i ∈ URL)//Determine it in the user revocation list or not
(2) exit;
(3)else
(4) distribute the updated parameters to the user i;
(5) for each attribute of the user i
(6)  calculate the corresponding key;
(7)  replace the property private key;
(8)  the user updates the private key;
(9) end for