About a decade ago almost all data centers were built on a traditional three- (or sometimes more) tier architectures that used the spanning tree protocol (STP). That prevented routing loops but also deactivated all the backup links, which accounted for almost half the ports in large environments. This caused organizations to significantly overspend on their networks.
At the heart of Microsoft?s Azure adoption strategy is the idea of the hybrid cloud, bridging on-premises datacenters and cloud computing. You don?t need to get rid of your old servers; instead, you connect them to the public cloud to take advantage of its scale and services, treating it as an extension of your existing datacenter.