Google Cloud Messaging - CCS (XMPP) vs HTTP server

Question

I\'ve read the documentation https://developer.android.com/google/gcm/index.html

and the only difference I can see is that a CCS (XMPP) based server allows bi-direct

Answer 1

XMPP messaging differs from HTTP messaging in the following ways:

Upstream/Downstream messages

• HTTP: Downstream only, cloud-to-device.
• XMPP: Upstream and downstream (device-to-cloud, cloud-to-device).

Messaging (synchronous or asynchronous)

• HTTP: Synchronous. App servers send messages as HTTP POST requests and wait for a response. This mechanism is synchronous and blocks the sender from sending another message until the response is received.
• XMPP: Asynchronous. App servers send/receive messages to/from all their devices at full line speed over persistent XMPP connections. The XMPP connection server sends acknowledgment or failure notifications (in the form of special ACK and NACK JSON-encoded XMPP messages) asynchronously.

JSON

• HTTP: JSON messages sent as HTTP POST.
• XMPP: JSON messages encapsulated in XMPP messages.

Plain Text

• HTTP: Plain Text messages sent as HTTP POST.
• XMPP: Not supported.

Multicast downstream send to multiple registration tokens.

• HTTP: Supported in JSON message format.
• XMPP: Not supported.