Should We Use Gcm (or New Fcm) With Openfire For Offline Pushnotification Messages?

It seams like to work with chat application, using openfire and smack there can be two ways below, First Way Smack makes a connection with the openfire server and it can receive

Solution 1:

1- Which way is better, secure and more reliable to use? A: Second Way

2- My application is working with way 1, should i switch to second way ? A: You should but obviously that would require Openfire skills to develop a plugin which will route messages to FCM.

3- what can be possible reasons to make sure that app stays connected in each and every way? and it consumes less batter as well? A: Simply said, if we reduce XMPP traffic, processing power can be saved and as a result reduction in battery consumption. But obviously for a chat application, that won't be the option. So for keeping the application interactive and battery friendly you should disconnect XMPP when app goes to background and rely on Push notifications (integration on server side).