R-1	Ui selects IDi and pwi.
R-2	Ui generates a random nonce RNr and computes H_PWi = h(pwi∥RNr).
	Ui sends the registration request {IDi, H_PWi} to GW in secure channels.
R-3	GW computes the following when it receives a registration request from Ui.
	H_IDi = h(IDi∥K)
	Xsi = h(H_IDi∥xs)
	Ai=h(H_PWi∥Xsi) ⊕ h(H_IDi ∥K)
	Bi = h(H_PWi ⊕ Xsi)
	Ci = XSi ⊕ h(IDs∥H_PWi)
	GW personalizes the smart card with IDs, H_IDi, h(·),Ai,Biand Ci.
	GW sends the smart card to Ui in secure channels.
R-4	Ui computes X_PWi = h(pwi) ⊕ RNr and adds X_PWi to the smart card.