The statement that defines the function of an Application Layer Gateway (ALG) is: The ALG uses software processes for managing specific protocols. An ALG is a security component that operates at the application layer (layer 7) of the OSI model and handles data associated with certain application protocols, such as SIP, FTP, RTSP, etc. An ALG acts as a proxy or intermediary between the client and the server applications and performs various functions, such as address and port translation, resource allocation, application response control, and synchronization of data and control traffic. An ALG can also inspect and modify the application payload to enable firewall or NAT traversal, prevent spoofing or DoS attacks, or enforce granular security policies based on application-specific commands. Reference := Application-level gateway - Wikipedia, What Is an Application Layer Gateway (ALG)? | F5, What is ALG ** Application Layer Gateway | 3CX

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