What is the primary usage of upstream messaging in GCM Cloud Connection Server?

Question

What is the usage of Cloud Connection Server that was announced at Google IO 2013?

I'm interested to know whether I can use the upstream messaging feature to send specific messages to GCM server. For example, can I send a command to delete a GCM notification that is stored on the GCM server? Or is it only used to send custom messages? If so, why do we need it at all?

Answer 1

According to the docs, there is no such feature to delete messages from the GCM server.

The upstream feature serves only for delivering messages from the device to your 3rd-party server. The advantages of using device to cloud messaging instead of establishing your own connection between your app and your server is improving battery life. It's also supposed to be faster than the regular GCM (since it's asynchronous).

Some of the benefits of CCS include:

• The asynchronous nature of XMPP allows you to send more messages with fewer resources.
• Communication is bidirectional—not only can the server send messages to the device, but the device can send messages back to the server.
• You can send messages back using the same connection used for receiving, thereby improving battery life.