Abstract: A method for operation of a communication network reduces leakage of data to an adversary that can observe signals transmitted through the communication network. The method includes generating a ranking to order operation of a plurality of nodes that exchange data in a group cryptographic key exchange process based on a leakage map of the nodes. The ranking minimizes leakage of data through a shared communication medium during the group cryptographic key exchange process. The method includes transmitting the ranking to the plurality of nodes through the shared communication medium, and performing, with the plurality of nodes, the group cryptographic key exchange process in an order of operation specified in the ranking to enable the plurality of nodes to exchange a shared cryptographic key through the shared communication medium while minimizing leakage of data.