Online communication offers organizations greater efficiency. However, online processes increase the threat level during message transfer. This necessitates researchers to develop and improve security protocols in order to enhance the security of communication lines. There are many evaluation tools such as BAN Logic to evaluate how secure authentication protocols' messages are. Despite the evaluation and acceptance of many authentication protocols, online communications remain insecure. We propose three approaches in order to increase the authenticity level; firstly, we propose to add the user's physical location as a new authentication factor into Kerberos protocol and call it N-Kerberos protocol. Secondly, we propose a new BAN logic based evaluation tool (N-BAN) to evaluate the N-Kerberos protocol. Finally, we validate the new form of Kerberos (N-Kerberos) using the new form of BAN (N-BAN) logic.