This document discusses Google Cloud Messaging (GCM) in Android. It explains that GCM is used to send messages from the cloud to Android devices and applications to enable push notifications. It describes how C2DM, GCM's predecessor, worked and the limitations it had. GCM overcomes these issues and provides advantages like allowing developers to leverage cloud computing and build more productive apps. The document outlines how GCM works, involving communication between an app server, the GCM server, and Android devices. It provides examples of how GCM is used in Google Play to deliver app updates and downloads.

1. Google Cloud Messaging In Android
Presented by –
Amardeep Vijay

2. C2DM
• Stands for Cloud to Device Messaging
• Used to send message from cloud to device or
application
• Support Push Notification
• C2DM retired and It’s time to GCM (Google
Cloud Messaging)
• Part of Google API

3. Poll And Push Notifications
• Poll :- Application contact cloud to check new
message
Disadvantage :-
• Extra Network Usages
• Reduced Battery life
Server/Cloud App / Device

4. Poll And Push Notifications (Cont…)
• Push :- Server contact Application or device whenever new
message is available
Advantages :-
• Reduce extra network uses
• Consumes less battery
Server/Cloud App / Device

5. How C2DM Works
App Server C2DM Server
App / Device

6. C2DM : Advantages & Disadvantages
Advantages :
• Using C2DM Developers can develop more
productive apps
• C2DM is connected to cloud so developers can
get benefits of cloud computing in their apps
Disadvantage :
• Internet connectivity is required
• Limited message size

7. Google cloud messaging

8. Why GCM ?
• Google migrated its products like :
Blogger to Google Blogs
Picasa to Google Image
AdMob to Google AdMob
Android marketplace to Google play
• So It’s time to C2DM to GCM
• Overcome disadvantages of C2DM

9. GCM
• Stands for Google Cloud Messaging
• Used for sending message from Cloud to
Device
• Introduce With Android 4.1 Jelly Bean as a
part of Google API 16
• Supports Push Notifications

10. How GCM Works
App Server GCM Server
App / Device

11. GCM (Cont…)
• GCM is two way Process –
1. Either GCM server registration or
2. No GCM server registration required : only
use GCM specific API or simply Google API 16
Application Signing(Generate Application
specific fingerprint)

12. Advantage of GCM
Advantages :
• Using GCM Developers can develop more
productive apps
• GCM is connected to cloud so developers can
get benefits of cloud computing in their apps
• GCM is now connected with GAE(Google App
Engine)

13. Working Example of GCM
Google Play :
• Google play uses GCM to install requested
android apps from Google play official site.
(http://play.google.com)
• Google play android app uses GCM to receive
requested apps from google play

14. Summary
• Message Multicasting for News
• Multiple Senders for Social Updates
• Time to Live for Events and Promos
• Messages with Payload for IM

16. Thank you for your time.