An application running within the Internet Information Services (IIS) web server on a Windows operating system can operate under a specific identity, often referred to as an application pool identity. This identity, configured within IIS, determines the security context under which the application code executes. One option for this identity is a built-in account like Network Service or a specifically created domain or local account. This allows the application to access resources, such as databases or file shares, with the permissions granted to that account. Choosing the appropriate identity is crucial for security and functionality.
Leveraging dedicated accounts for web applications enhances security by implementing the principle of least privilege. Instead of running under a powerful administrative account, the application operates with only the necessary permissions. This restricts potential damage from security vulnerabilities or malicious code. Properly configured identities facilitate auditing and logging, allowing administrators to track application activity and identify potential security breaches more easily. This granular control over access rights significantly strengthens the overall security posture of the web server.