Azure Global Infrastructure

Azure's global infrastructure is one of the largest in the world. It spans more than 60 regions, hundreds of data centres, and a vast fibre-optic network that connects them all. Understanding how Azure organises this infrastructure — into regions, availability zones, and edge locations — is essential for designing resilient, performant, and compliant solutions.

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Geographies

At the highest level, Azure groups its infrastructure into geographies. A geography is a discrete market, typically defined by geopolitical boundaries, that contains one or more Azure regions. Geographies ensure that data residency, sovereignty, and compliance requirements are respected.

Examples of Azure geographies:

• United Kingdom (UK South, UK West)
• United States (East US, West US, Central US, and many more)
• Europe (North Europe in Ireland, West Europe in the Netherlands)
• Asia Pacific (Southeast Asia in Singapore, East Asia in Hong Kong)

Each geography typically contains at least two regions paired together for disaster recovery purposes.

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Regions

An Azure region is a set of data centres deployed within a latency-defined perimeter and connected through a dedicated regional low-latency network. Each region is a separate geographic area.

Key characteristics of Azure regions:

• Independent infrastructure — each region has its own power, cooling, and networking
• Service availability varies — not every service is available in every region
• Pricing differs — the cost of the same service can vary between regions
• Data residency — your data stays in the region you choose (unless you explicitly configure replication elsewhere)

Azure currently has 60+ regions, more than any other cloud provider. When choosing a region for your workloads, you should consider:

1. Proximity to users — deploy close to your customers for lower latency
2. Service availability — ensure the services you need are available in that region
3. Compliance requirements — certain regulations require data to remain in specific geographies
4. Pricing — costs vary between regions
5. Region pairs — consider which region your chosen region is paired with for disaster recovery

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Region Pairs

Most Azure regions are paired with another region within the same geography, typically at least 300 miles apart. Region pairs provide a built-in disaster recovery strategy.

Benefits of region pairs:

• Planned maintenance is applied to only one region in a pair at a time, minimising downtime
• During a broad outage, recovery of one region from each pair is prioritised
• Some services (like geo-redundant storage) automatically replicate data to the paired region
• Updates are rolled out sequentially across paired regions, not simultaneously

Example region pairs:

Primary Region	Paired Region
UK South	UK West
East US	West US
North Europe	West Europe
Southeast Asia	East Asia

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Availability Zones

Availability Zones are physically separate locations within an Azure region. Each zone has its own independent power supply, cooling, and networking. Regions that support availability zones typically have three zones, labelled Zone 1, Zone 2, and Zone 3.