What is required to block access to web proxies on TCP port 8080?

To successfully block access to web proxies operating on TCP port 8080, it is essential to configure a firewall rule that specifies several key components. The correct answer outlines the necessary criteria: chain, action, protocol, and port.

The chain refers to the context in which the firewall rule is applied, determining whether the rule is filtering incoming, outgoing, or forwarded packets. Action specifies what the firewall should do if the criteria of the rule are met, such as accepting or dropping the packets. Protocol indicates the specific transmission protocol in use; in this case, it is TCP, which is the protocol used by web proxies operating on port 8080. Finally, specifying the port is critical since the aim is to target traffic specifically on TCP port 8080.

By combining these elements—chain to define the packet flow context, action to dictate the response, protocol to specify TCP, and port to identify the targeted service—this configuration effectively blocks access to the web proxy service. This ensures that unwanted traffic attempting to use that specific port is handled as desired, providing a more secure network environment.