Push notification architecture for very high volume

Is Apple push notification architecture setup for sending very high volume (dozens of notifications per hour) ? Is this allowed by Apple开发者_开发知识库 ? What are the constraints/limits ? Is it reliable ? Are there some delays ? Is there a price to pay for using their service ?

In order:

1. Yes.
2. Yes.
3. I'm not sure.
4. Mostly; delivery of notifications isn't guaranteed, but the service will attempt to deliver the latest notification your app's generated when a device reappears on the network after being unavailable.
5. Again, there are no particular guarantees, but if the target device is on a good 3G or wifi connection then you can expect the notifications to be delivered within a few seconds of being sent.
6. No. You do, however, need to run your own push notification server (or use a third-party notification-delivery service), which may get costly if you're using a lot of bandwidth and CPU time for your notifications.

For more information, check out the Apple Push Notification Service section in the developer docs.

You should read the Local and Push Notification Programming Guide, chapter Apple Push Notification Service.