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

Table 1

Summary of the registration phase of our scheme.

User (𝑈𝑖)	Remote server (𝑆𝑗)
Selects 𝐼𝐷𝑖, 𝑃𝑊𝑖.
Generates secret number 𝐾.
Computes 𝑅𝑃𝑊𝑖= ℎ(𝐼𝐷𝑖‖𝐾‖𝑃𝑊𝑖).
−−−−−−−−−−→^𝐼𝐷𝑖,𝑅𝑃𝑊𝑖
(via a secure channel)	Generates secret number 𝑋𝑠.
	Computes 𝑟𝑖=ℎ(𝐼𝐷𝑖‖𝑅𝑃𝑊𝑖),
	𝑒𝑖=ℎ𝐼𝐷𝑖‖𝑋𝑠⊕𝑟𝑖,
	𝑇𝐷𝑖=𝑁𝐼𝐷𝑖⊕ℎ(𝐼𝐷𝑖‖𝑟𝑖), and 𝐷𝑖=𝑇𝐷𝑖.
	←−−−−−−−−−−−−−−−−−−−−−−−−^𝑟𝑆𝑚𝑎𝑟𝑡𝐶𝑎𝑟𝑑𝑖,𝑒𝑖,𝑇𝐷𝑖,𝐷𝑖(⋅),ℎ−−−−−−−−−
	(via a secure channel)
Stores 𝐾 into the smart card’s memory.