Efficient Multifactor Two-Server Authenticated Scheme under Mobile Cloud Computing

Table 1

Basic concepts of BAN.

Symbols	Meaning
	The specific main body
	The specific public key of a
	The corresponding private key of a
	Any main body
	Any sentence
	Any key
P believes X	P believes X
P sees X	P has received X
P said X	P has sent X
P controls X	P has jurisdiction of X
(X,Y)	X links to Y
fresh(X)	X is fresh
	The result of X encrypted by K
	P and Q communicate with each other by shared key K
	P and Q X is one-way hash function
	K is the pubic key of P
	X is the secret value between P and Q