We have a mobile application that uses Google Cloud Messaging. This means our internal server has to communicate with Google's GCM server at android.googleapis.com on a specific port.
Our IT team is reluctant to open this outgoing port to any machine, and therefore would like to configure the firewall so we can only talk to the Google GCM server on this port.
This is where it get's tricky. In their developer docs, Google gives the following configuration advice:
"Note: If your organization has a firewall that restricts the traffic to or from the Internet, you need to configure it to allow connectivity with GCM in order for your Android devices to receive messages. The ports to open are: 5228, 5229, and 5230. GCM typically only uses 5228, but it sometimes uses 5229 and 5230. GCM doesn't provide specific IPs, so you should allow your firewall to accept outgoing connections to all IP addresses contained in the IP blocks listed in Google's ASN of 15169."
Is there an authoritative source of what IP Addresses make up ASN 15169? I've done a lot of searching, and have come up with some dodgy looking sites. I was hoping to fine the canonical list somewhere.
Thanks for your help.