I have been pondering for some time how to communicate in the event of a true emergency. I don’t have a good answer.
Today’s Internet has very little headroom. A loss of 30% to 50% of capacity could completely gridlock communications. While that is less likely to happen during a regional storm than 40 years ago, it still could happen in a national emergency or if the US Government invoked call controls.
In the old days it was fun knowing I could get calls through during a snowstorm while others could not. In the old days the lines would block very easily because they couldn’t take more than about a 25% surge in traffic.
When the network overloaded in a region inbound calls to the region would all be blocked. The reason is that it was deemed more important to keep lines open for people calling out of a region (such as to say that you were OK.) it was found that call completion percentages were higher calling out of a region and into a disaster. So the norm was to allow out calls but not in calls.
This could be gamed. I took a certain joy during a snowstorm in getting my calls through.
The easiest trick was to call through an operator. You could call collect, or use third party billing. One time I called my parents (who were in the midst of a terrible snowstorm) by third party billing the call to the number I was calling from. The operator didn’t even mention that it was odd that I would use an operator to third party bill to my own number.
You see, the lines were also kept open for operators. So third party billing would access these open lines. The lines were kept open for operators for two reasons. One was that operator rates were higher so these calls were more profitable. But the other reason was that emergency responders were given a code-word and number to signal that they had a priority need to use the lines.
If the network was very badly overloaded you could use a coin phone. Dial tones would be rationed during an overload, but certain classes of phone service such as coin phones weren’t throttled. Their calls would also go through at a higher rate.
Today I don’t know how I could get my calls to go through ahead of others. The internet sort of makes it difficult to jump the line.