Mutual authentication is of two types: Certificate-based (see Figure 25–4) User name/password-based (see Figure 25–5)

Mutual authentication is when two sides of a communications channel verify each other’s identity, instead of only one side verifying the other. For example, a client and a server using mutual authentication take steps to independently verify each other’s identity, instead of only the client authenticating the server.

How Mutual Authentication Works

1. Server responds with ServerHello message selecting the SSL options.
2. Server sends Certificate message, which contains the server’s certificate.
3. Server requests client’s certificate in CertificateRequest message, so that the connection can be mutually authenticated.

Mutual authentication, also called two-way authentication, is a process or technology in which both entities in a communications link authenticate each other. With mutual authentication, a connection can occur only when the client trusts the server’s digital certificate and the server trusts the client’s certificate.

Mutual authentication can prevent spoofing attacks because the server will authenticate the user as well, and verify that they have the correct session key before allowing any further communication and access.

Mutual TLS is a widely used, secure, authentication technique in enterprise environments to ensure the authenticity of the clients to server and vice versa. It facilitates authentication via certificates followed by the establishment of an encrypted channel between the parties.

Mutual authentication, also known as two-way authentication, is a security process in which entities authenticate each other before actual communication occurs. In a network environment, this requires that both the client and the server must provide digital certificates to prove their identities.

Mutual authentication is of two types:

• Certificate-based (see Figure 25–4)
• User name/password-based (see Figure 25–5)

There are three common factors used for authentication: Something you know (such as a password) Something you have (such as a smart card) Something you are (such as a fingerprint or other biometric method)

Multi-factor authentication (MFA) is a method of logon verification where at least two different factors of proof are required. MFA is also referred to as 2FA, which stands for two-factor authentication.

Mutual TLS, or mTLS for short, is a method for mutual authentication. mTLS ensures that the parties at each end of a network connection are who they claim to be by verifying that they both have the correct private key. The information within their respective TLS certificates provides additional verification.

So in a web-based mutual authentication process, communication can occur only if the client and the server trust each other’s digital certificates. The certificate exchange is done through Transport Layer Security (TLS) protocol. The core essence of this process is that neither party trusts the other until identities are proven.

TLS certificates can be used for this type of mutual authentication if both sides have one. 3. Username and password: Despite the name, this method of mutual authentication still uses a certificate on the server side. The server presents a certificate to the client, which verifies the certificate.

From a high-level point of view, the process of authenticating and establishing an encrypted channel using certificate-based mutual authentication involves the following steps: A client requests access to a protected resource. The server presents its certificate to the client. The client verifies the server’s certificate.

Mutual authentication. Mutual authentication or two-way authentication refers to two parties authenticating each other at the same time, being a default mode of authentication in some protocols ( IKE, SSH) and optional in others ( TLS ). By default the TLS protocol only proves the identity of the server to the client using X.509…