What is Mutual Authentication?

Sometimes referred to as two-way authentication, mutual authentication is an approach within the electronic communications process that allows both the point of origin and the point of termination of a communication link to verify or authenticate each other. This is a common process that is part of the basic function of many different communication systems, both private and public. The essential reason for mutual authentication is to ensure that both parties are communicating with legitimate entities and not a party that is attempting to appear to be someone else.

Within a private network environment, such as within the confines of a business, mutual authentication functions as a means of allowing the client to verify or authenticate the server. This helps the client or end user know that he or she is connecting with the company server and will be able to access all data on the server that is allowed with his or her access credentials. At the same time, the server will authenticate the client, checking the entered credentials and clearances against the profile created for the client. If everything appears to be in order, the communication will continue. However, if either the client or the server detects anything suspicious, the communication link usually shuts down as part of a security measure.

More and more businesses are making use of mutual authentication in order to protect both the business and the customers from online fraud, identity theft, and other issues. For example, many financial institutions not only require a user name and password to enter accounts in an online environment, but also an additional layer of identification, such as the ability to identify the computer that the end user normally utilizes to access the site. If the computer is not recognized, the security measures may require what is known as two-factor authentication. This additional layer may be an image associated with the client profile or some similar extra mechanism the end user must respond to before entry is granted.

The basic method of engaging in mutual authentication involves making use of what is known as Transport Layer Security protocol. Essentially, this type of protocol works to allow the server to identify the latest timestamp and other data associated with the client. If the purported client is actually a phishing site, then TLS will sense something is wrong, and break the connection.