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The entire process was badly bungled. The FCC designed a nicely tiered alert system for mobile phones. The CRTC then adopted the same system but tossed out al

The entire process was badly bungled. The FCC designed a nicely tiered alert system for mobile phones. The CRTC then adopted the same system but tossed out all but the "Presidential" level. Then they delegated responsibility for what to alert about to local authorities. The end result is cops in Burlington sending end of the world alerts that can't be silenced to people 1500 km and 15 hours away in Thunder Bay about events that took place 2 hours ago. It's complete lunacy. The tone is so disruptive and loud people are calling 911 to complain. It's so jarring I'm shocked it hasn't resulted in fatal car collisions. I've been in the states during amber alerts and even natural disaster warnings and the process is simple and effective. The alerts come in and you action them if warranted. Ours are literally the end of the world tone no matter what.

garaetjjte 7y ago
How those alerts work technically? They are SMS with special header or entirely separate message type? (eg. in Poland alerts are sent as plain old SMS)
- theluketaylor 7y ago
  It's cell broadcast which is related to SMS but slightly different. https://en.wikipedia.org/wiki/Cell_Broadcast https://en.wikipedia.org/wiki/Cell_Broadcast
- jsjohnst 7y ago
  No, they are not done like SMS. Think of SMS like a normal IP packet, it has a source and destination. Belaboring the analogy, the WEA messages are more multicast packets. WEA messages are encapsulated in Cellular Broadcast data (CB Data) payloads which are then encapsulated in System Information Blocks (SIB12 specifically). The way they are “routed” to your phone is by being near a tower in the coverage area of the alert. Even if you weren’t in range of the tower when the alert initially went off, you’ll still receive the message as soon as you are within range of the tower(s) broadcasting it (assuming the alert hasn’t been cleared). Each payload has the equivalent of a payload ID which is supposed to prevent duplicate notification on your device of the same alert (but for different reasons, isn’t always done right).

garaetjjte 7y ago

How those alerts work technically? They are SMS with special header or entirely separate message type? (eg. in Poland alerts are sent as plain old SMS)

theluketaylor 7y ago
It's cell broadcast which is related to SMS but slightly different. https://en.wikipedia.org/wiki/Cell_Broadcast https://en.wikipedia.org/wiki/Cell_Broadcast
jsjohnst 7y ago
No, they are not done like SMS. Think of SMS like a normal IP packet, it has a source and destination. Belaboring the analogy, the WEA messages are more multicast packets. WEA messages are encapsulated in Cellular Broadcast data (CB Data) payloads which are then encapsulated in System Information Blocks (SIB12 specifically). The way they are “routed” to your phone is by being near a tower in the coverage area of the alert. Even if you weren’t in range of the tower when the alert initially went off, you’ll still receive the message as soon as you are within range of the tower(s) broadcasting it (assuming the alert hasn’t been cleared). Each payload has the equivalent of a payload ID which is supposed to prevent duplicate notification on your device of the same alert (but for different reasons, isn’t always done right).