The topic of the final paper is the analysis of authentication protocols, ie their security analysis. Authentication is the process of verifying a user's identity when accessing a service, in this case a web server. If the authentication is authenticated, then usually follows the authorization process which gives the user, based on his identity, certain authority over the resources of the web server. From this it is obvious the importance of accurate identification and verification of identity, ie the importance of the security aspect of the authentication process. Security practice defines 3 basic types of authentication by which the user confirms his identity: using something the user knows (password), something the user owns (credit card, ID token) or something the user is (user biometric data). For convenience and simplicity, password authentication is most commonly used for authentication when accessing web servers. The implementation of authentication in different ways is the topic of this paper as well as the risks to which such authentication is exposed. To avoid such risks, it is possible to implement advanced authentication methods, which will also be described later in the document.