Common use of Communication Model Clause in Contracts

Communication Model. The communication model of our proposed scheme is shown in Figure 1. It includes three kinds of entities: the gateway node GWN, the user U and the sensor node S. A secure communication channel can be established between U and S. Once the user U intends to request a certain service or access the data via GWN, the authentication session is initiated. U first sends an authentication request the message M1 to GWN which requests GWN for authentication; after checking the validity of messages from U, GWN sends the message M2 to S. When receives the message M2 from GWN, S replies the confirmation message about session key establishment with message M3 to GWN. Then GWN verifies M3, generates and sends the message M4 including the message M3 to U. At last, after U authenticating GWN and S, U securely establishes a session key with S successfully. (1) M1 (2) M2