C2DM未交付到“睡眠”设备

Question

I have a question about C2DM. It is not a configuration, IDs, or usage question. I think I have all that squared away. Instead it is about a specific failure scenario.

I send a C2DM to a device and it does not wake from sleep. It is using AT&T with Wi-Fi disabled and is not plugged into the charger. I think all of those are important things to mention.

When I turn on the device I can browse the internet, sync gmail, and send/receive xmpp packets from within the application I am writing - the same one that embeds the C2DM broadcast receiver.

The device is now in a state where there is an undelivered C2DM messages but otherwise seems to be connected to the Internet and running. At this point if I go into and out of airplane mode I immediately get the “missing” C2DM message.

Question: Anybody else seeing this and have an explanation?

(I'm used to this stuff on WinMo with junky RILs - but don't know what to try on Android)

Edit One: I understand that C2DM is not guaranteed delivery. But, if it always fails under certain circumstances that is a different thing altogether. I am seeing it fail on sleeping devices and not recovering until I cycle airplane mode. Hopefully this makes my question more unique than one that can be answered with "C2DM delivery is not guaranteed".

Edit Two: I can not reproduce this on a WiFi Xoom against my home router. It is easily reproducible on the Galaxy Tab 8.9 with a stock ROM. Could it be that be AT&T is closing the connection in a way not detected by the C2DM client code and that cycling airplane mode forces a reconnection? That sort of limitation should be documented or considered a bug right?

Answer 1

In my case the problem is the at&t 4g lte APN (at this time in my market)

The APN strongly affects C2DM.