GCM API key vs Sender ID

google-cloud-messaging, push-notification

Solution

I've kinda figured it out on my own:

- API key is generated on console and is used by 3rd party server to authenticate/authorize with GCM.

- Sender ID is used by Android app to register a physical device with GCM to be able to receive notifications from GCM from particular 3rd party server.

- Registration ID is a result of registration of physical device to GCM with Sender ID.

Problem

I am confused about GCM Sender ID and API key. I'm responsible for building 3rd party server that will send notifications to Android app. Which one do I have to store on server side? API key or Sender ID? Who is responsible for creating both, Android developer or me?

Original source