Apple designed iMessage in a way that makes it almost impossible to block

iMessage is extremely difficult to block, according to 9to5Mac.

The service’s technical architecture is built in such a way that disabling it could disrupt the functioning of all iPhones in a given country. The discussion emerged following Russia’s recent decision to block FaceTime.

Mastodon users pointed out that iMessage traffic is routed through the same servers as the Apple Push Notification service (APNs). This means that any attempt to block iMessage IP addresses would also shut down push notifications on all iOS devices — no alerts from banks, messengers, email clients or any other apps would come through.

It’s believed that Apple didn’t do this to counter censorship, but to prevent mobile operators from blocking iMessage. When the service launched, it threatened operators’ SMS revenue, and they could have tried to limit a competing service.