A Lightweight Three-Party Mutual Authentication Protocol for Internet of Health Things Systems

Table 1

Parameters, methods, and symbols.

Notation	Description	Notation	Description
TA	Cloud authentication server		A wearable Internet of Things connector
	Server key pair		Effective time
WS	A wearable device		Current time of device i
	Selected elliptic curve base point		Determine whether they are equal
	Status of equipment		XOR operation
||	Concatenation operation	SK	Session key
PID	Temporary ID of the patient after binding with IotC	PTC	Temporary identification code of the patient after binding with IotC
NID	Temporary network ID authorized by TA	Ac	Temporary authentication code authorized by the server
a, c, x, y	Random parameters		Collision-resistant hash function
	Authentication code of device I		Management key for device i
	User’s biometric information		Deterministic reproduction function
	Probabilistic generation function		Reproduction parameter from
	Biometric key from	E ()/D ()	Encryption/decryption method