A Robust IoT-Based Three-Factor Authentication Scheme for Cloud Computing Resistant to Session Key Exposure

Table 3

The notations and rules in BAN logic.

Symbols	Description
P, Q	The principals
X	A statement
	see , gets a message that consists of
	said , sent a message that consists of
	is convinced that is true
	has jurisdiction over
	is a secret shared by and
	is combined with a secret
	is encrypted with a key
	is fresh
Belief rule
Message meaning rule (Rule 1)	or
Nonce-verification rule (Rule 2)
Jurisdiction rule (Rule 3)