In a Circuit-level gateway what does circuit-level filtering inspect? Choose one.Answer instructionsPacketsConnectionsPortsSessions

Step 1: Break Down the Problem

The question asks about the primary focus of circuit-level filtering in a circuit-level gateway. The options provided are various aspects of network communication.

Step 2: Relevant Concepts

Circuit-level gateways operate at the transport layer of the OSI model. They do not inspect the contents of the packets (like application-layer gateways) but rather focus on connections and sessions.

Step 3: Analysis and Detail

• Packets: Circuit-level gateways do not primarily inspect packet contents.
• Connections: This refers to the establishment and maintenance of the logical connections between communicating devices, which is a key aspect of circuit-level filtering.
• Ports: While ports are related to the connections, circuit-level filtering does not inspect port numbers specifically.
• Sessions: This term is closely related to connections, but it generally encompasses the entire session management, which is ultimately what circuit-level gateways focus on.

Step 4: Verify and Summarize

The main focus of circuit-level filtering is on monitoring the connections (or sessions) established between hosts in the network, ensuring that these connections are valid and authorized.

Final Answer

Connections