Today's outages got me thinking, when a network has issues they'll sometimes call on-call engineers. All the main networks will have a NOC staffed 24/7, but they will need to call up certain specialist engineers and managers at certain hours I'm sure.
Do networks rely on their own network, or do they typically issue out competitor phones or sims as part of a BCP just incase?
Do networks rely on their own network, or do they typically issue out competitor phones or sims as part of a BCP just incase?

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