Good that emergency calls still work. In the Netherlands we had a handful of service interruptions (for some regions/providers) in the last few years, and the emergency numbers went down as well. If I remember correctly, the problems were mostly caused by software.
It depends on the infrastructure but sometimes emergency calls are routed differently, sometimes over completely different systems. There's a system in the US called GETS that allows federal, state, and local government agencies to make high priority calls over normal commercial phone systems and will also make use of government only phone lines, whatever will make the connection. The agency gets a special code and a certain phone number they dial first (just like using one of those old long distance cards). There is dedicated bandwidth just for these kinds of phone calls so even if all the lines are full, there is a guaranteed 90% call completion rate if the call volume is 8 times higher than normal.
There's a wireless version of this too although it doesn't quite work the same so I'm not sure how effective it really is.
The Netherlands has a network for the emergency services that is entirely separated from the normal phone network ("Noodnet"). It has a limited service and bandwidth and normally has no interconnection with the normal phone network (so is not intended or usable for emergency calls from the public), but is designed to be very resilient. I don't think it is used when the normal phone network is still functioning. I have no idea how they test it; it must all be rather expensive.
Comments
Good that emergency calls still work. In the Netherlands we had a handful of service interruptions (for some regions/providers) in the last few years, and the emergency numbers went down as well. If I remember correctly, the problems were mostly caused by software.
It depends on the infrastructure but sometimes emergency calls are routed differently, sometimes over completely different systems. There's a system in the US called GETS that allows federal, state, and local government agencies to make high priority calls over normal commercial phone systems and will also make use of government only phone lines, whatever will make the connection. The agency gets a special code and a certain phone number they dial first (just like using one of those old long distance cards). There is dedicated bandwidth just for these kinds of phone calls so even if all the lines are full, there is a guaranteed 90% call completion rate if the call volume is 8 times higher than normal.
There's a wireless version of this too although it doesn't quite work the same so I'm not sure how effective it really is.
The Netherlands has a network for the emergency services that is entirely separated from the normal phone network ("Noodnet"). It has a limited service and bandwidth and normally has no interconnection with the normal phone network (so is not intended or usable for emergency calls from the public), but is designed to be very resilient. I don't think it is used when the normal phone network is still functioning. I have no idea how they test it; it must all be rather expensive.