A critical assured service that includes a network management system and an A/B switch. The A/B switch having at least four ports with a first port being connected to the network management system over a dedicated line. The A/B switch sending and receiving messages and/or signals from the network management system over the first dedicated line. The A/B switch automatically switching telephone service from a first point of presence to a second point of presence after the A/B is signaled that the first point of service is inoperable.
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