Azure is the public cloud infrastructure provided by Microsoft and some Partners worldwide. Debian images and support infrastructure inside Azure is maintained by Debian developers at credativ.
Images
Mirrors
There exists high available and distributed Debian mirrors inside Azure. They provide anything for architectures *amd64*, *i386* and *source* from main and security archive.
deb http://debian-archive.trafficmanager.net/debian jessie main deb-src http://debian-archive.trafficmanager.net/debian jessie main deb http://debian-archive.trafficmanager.net/debian-security jessie/updates main deb-src http://debian-archive.trafficmanager.net/debian-security jessie/updates main