A Web Security Protocol is a set of rules, standards, and procedures designed to protect web applications, websites, and online communications from unauthorized access, data theft, modification, and cyberattacks. These protocols ensure that information exchanged between users and web servers remains confidential, authentic, and intact. They play a critical role in web application testing and auditing because auditors verify whether appropriate security protocols are implemented correctly to safeguard sensitive information such as usernames, passwords, financial data, and personal records. Web security protocols provide essential security services including authentication, authorization, confidentiality, integrity, and non-repudiation. Authentication is the process of verifying the identity of a user, device, or application before granting access to resources. Authentication protocols define the methods and procedures used to perform this identity verification securely. During web application testing, authentication mechanisms are examined to identify weaknesses such as weak passwords, session hijacking, replay attacks, and credential theft. One of the most common authentication protocols is Password Authentication Protocol (PAP). PAP is a basic authentication protocol in which the user's username and password are transmitted to the authentication server for verification. The credentials are generally sent in plain text, making PAP vulnerable to interception if encryption is not used. Because of its weak security, PAP is rarely recommended for modern web applications. An example