Region

CSPs have Data Centers at various locations across the globe. Those various locations are called Regions. This has a number of purposes, among which:

• To provide Geo-Redundancy.
• To reduce Latency: systems respond faster if clients in Australia can use services in Australia instead of services in the US.
• To distribute load.

CSPs also tend to have more than one datacenter relatively close to one another within a Region. These datacenters within a Region are called Availability Zones. This serves a number of purposes, among which:

• Redundancy and low Latency: If Redundancy would have to be achieved with Regions, then that would result in higher Latencies, because Regions are pretty far apart (i.e. west us, central us, east us). By having multiple datacenters within a Region Redundancy can be achieved with little latency, because the datacenters within a Region are relatively close to one another (10 miles, give or take).