Comment by acdha
2 years ago
This would only work if the protocol doesn’t have the concept of retries, which it does. They’d have to block all communications which would be highly noticeable - especially since you’d get a flurry of messages any time you opened the app or migrated onto a Wi-Fi network.
I suppose it depends on which protocol, and which app, we're talking about, but...Interesting. Good analysis!
It's conceivable that connectivity checks flow to other servers than delivery traffic, and these are passed-through. Although addressing your more general critique of the "flurry" (good word! :)), requires noting that accomplishing this capability would involve compromising the app's servers. Such backdoors are again not outside the realm of possibility in the given threat model.
Do you see any possibilities for interference in the push interception capability described?