Which component handles the physical boundary connection between a carrier's leased line and customer equipment, performing line encoding and conditioning?

Which component handles the physical boundary connection between a carrier's leased line and customer equipment, performing line encoding and conditioning?

• A. Proxy server
• B. Router
• C. Connects a T-carrier line to customer equipment and performs line encoding/conditioning
• D. Switch

Answer: (C)

The key idea here is the device that sits at the boundary between the carrier’s leased line and the customer’s equipment, turning the provider’s digital signal into something the customer gear can use. For a T-carrier line, that job is done by a CSU/DSU. It terminates the provider’s circuit on the customer side and performs line encoding and conditioning—shaping the signal, ensuring the proper timing and voltage levels, and protecting against issues on the line so the customer equipment (router, switch, or other DTE) can communicate reliably. Proxy servers, routers, and switches handle data forwarding or services, not the physical demarc and the required line encoding/conditioning for the carrier’s circuit.

The key idea here is the device that sits at the boundary between the carrier’s leased line and the customer’s equipment, turning the provider’s digital signal into something the customer gear can use. For a T-carrier line, that job is done by a CSU/DSU. It terminates the provider’s circuit on the customer side and performs line encoding and conditioning—shaping the signal, ensuring the proper timing and voltage levels, and protecting against issues on the line so the customer equipment (router, switch, or other DTE) can communicate reliably.

Proxy servers, routers, and switches handle data forwarding or services, not the physical demarc and the required line encoding/conditioning for the carrier’s circuit.