A Robust and Effective Smart-Card-Based Remote User Authentication Mechanism Using Hash Function

Table 2

Summary of the login phase of our scheme.

User (𝑈𝑖)/smart card (𝐶𝑖)	Remote server (𝑆𝑗)
Inputs 𝐼𝐷^∗𝑖, 𝑃𝑊^∗𝑖.
Computes 𝑅𝑃𝑊^∗𝑖 and 𝑟^∗𝑖.
Checks if 𝑟^∗𝑖=𝑟𝑖. If it holds
computes 𝑁𝐼𝐷^∗𝑖=ℎ(𝐼𝐷^∗𝑖‖𝑟^∗𝑖)⊕𝐷𝑖,
𝑀1=𝑒𝑖⊕𝑟^∗𝑖, 𝑀2=𝑀1⊕𝑅𝑐⊕𝑇𝑐,
and 𝑀3=ℎ(𝐼𝐷^∗𝑖‖𝑅𝑐‖𝑇𝑐).
−−−−−−−−−−−−−−−−−−^⟨𝑁𝐼𝐷∗𝑖,𝑀2,𝑀3,𝑇𝑐⟩−→
(via a public channel)