Isolation of a central office occurs when

Isolation of a central office occurs when

• A. The links between the central office serving a PSAP and the remainder of the communications network are interrupted.
• B. The DBMS fails
• C. The PSAP building is destroyed
• D. The Tandem Switch fails

Answer: (C)

Isolation of a central office means the facility housing the 9-1-1 equipment becomes unusable and cut off from the rest of the network, so no calls can be processed from that site. When the PSAP building is destroyed, there’s no location to operate from, no power, and no access to the central office equipment—effectively removing the central office from service. That’s why this scenario best represents isolation. A broken network link, a DBMS failure, or a tandem switch failure are significant problems, but they don’t by themselves render the entire central office unavailable in the way the destruction of the PSAP facility does.

Isolation of a central office means the facility housing the 9-1-1 equipment becomes unusable and cut off from the rest of the network, so no calls can be processed from that site. When the PSAP building is destroyed, there’s no location to operate from, no power, and no access to the central office equipment—effectively removing the central office from service. That’s why this scenario best represents isolation. A broken network link, a DBMS failure, or a tandem switch failure are significant problems, but they don’t by themselves render the entire central office unavailable in the way the destruction of the PSAP facility does.