Whether natural or man-made, major disasters are times when mobile networks are put to the test. And in those times there just isn’t enough capacity available when everyone tries to call their friends and loved ones. But SMS messages will get through.
Like Google, you may think a SIM farm is an old video game (go ahead, Google it!). But when it comes to SMS messaging, a SIM farm is nothing like a fun and harmless video game. SIM in this context is referring to a subscriber identity module, or SIM card in a mobile device. Every mobile on a GSM network uses one. It contains information about the owner and mobile including number, contact lists, network authorisation.
Coverage maps from mobile providers all tout the best mobile phone coverage. But even the best ones will have holes in their service if you look closely. It all really depends on geography and signal strength. In areas with hills and valleys, you could lose signal just by being on one side of the hill while the mobile tower is on the other.
A text message is a very small and condensed piece of communication in contrast to voice messaging or video broadcast. Consequently text messages can get through when network capability is degraded to an extent that makes other options unviable.
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