An application proxy firewall needs have multiple proxy programs if it is to filter multiple application protocols.

• A. TRUE
• B. FALSE
• C. Sometimes
• D. Not necessarily

Answer: (A)

An application proxy firewall works at the application layer and uses protocol-specific proxies to understand and control traffic. Each application protocol has its own commands, responses, and session behavior, so to accurately filter and enforce policies for different protocols you typically need dedicated proxy logic for each one (for example, separate handling for HTTP, FTP, SMTP, and DNS). This separation allows the firewall to inspect the protocol correctly, enforce rules, and manage sessions without misinterpreting traffic. While some modern systems may consolidate handling under a single framework, the conventional design relies on multiple protocol-specific proxies, so the statement is true.