Common use of Storage overhead analysis Clause in Contracts

Storage overhead analysis. Storage overhead must be taken into consideration to design efficient security schemes in the context of IoT. Thus, we study the storage cost at specific moments in the sensor node as a constrained object. First, after the registration phase, the sensor node stores (Idi, MSIdi, Xi) which means 40 bytes. Second, after the authentication phase, we have two cases: Case ‘not in the area’: the sensor node has in its storage (Idi, MSIdi, Xi, N, Z, S, W) which means 72 bytes. Case ‘in the area’: the sensor node has in its storage (Idi, MSIdi, Xi, N, M) which means 56 bytes. Third, at the end of the key establishment phase: Case ‘not in the area’: the sensor node stores (Idi, MSIdi, Xi, N, Z, S, W, K1, K2, K) that consumes 104 bytes, and it is the maximum used storage. Case ‘in the area’: the sensor node stores (Idi, MSIdi, Xi, N, M, K) that consumes 72 bytes. Finally, after the key establishment phases, the sensor node can delete (N, Z, S, W, K1, K2) in the first case, and (N, M) in the second case. Thus, it stores only 56 bytes (Idi, MSIdi, Xi, K). As a result from the storage overhead analysis of proposed authentication and key agreement scheme, we deduce that the proposed scheme has a very low storage cost which enhances the scheme performance.