What is a primary function of an application level gateway?

An application level gateway, also known as a proxy firewall, primarily functions by examining packets for application-specific commands. This means that it operates at a higher layer of the OSI model, focusing on the application layer. When data packets are sent and received, the gateway analyzes the content and behavior of the protocols being used, such as HTTP or FTP.

By reviewing the application layer data, the gateway is capable of making more informed decisions about whether to allow or deny traffic based on the specifics of the application protocol. This deep packet inspection helps in identifying potentially harmful actions or unauthorized data transfers that could otherwise bypass traditional network filtering methods.

This capability makes application level gateways essential for enforcing security policies that require understanding of the applications themselves, as they can detect and control malicious activities that may not be visible through standard packet filtering methods.