Azure Cosmos DB Global Distribution

Azure Cosmos DB is a globally distributed, multi-model database service that allows you to distribute your data across multiple regions worldwide. Global distribution in Cosmos DB enables low-latency access to data for users in different areas, as well as high availability and disaster recovery capabilities.

When creating a Cosmos DB account, you can choose which regions you want to distribute your data. Each region is called a "write region," and Cosmos DB automatically replicates your data to all other regions you have selected. Your data is always available, even in a regional outage or disaster.

Cosmos DB also supports multi-homing, which allows you to read data from the closest region to the user, reducing latency. When a client connects to Cosmos DB, it is directed to the nearest read region, and the data is read from the closest replica.

In addition, you can also choose the level of data consistency for your application, allowing you to strike a balance between data consistency and low-latency access.

Global distribution in Cosmos DB also enables you to comply with data sovereignty and compliance requirements, as you can choose to store your data in specific regions in compliance with regulations and industry standards.

According to the Microsoft documentation:

Within a data centre, we deploy and manage the Azure Cosmos DB on massive stamps of machines, each with dedicated local storage. Azure Cosmos DB is deployed across many clusters within a data centre, each potentially running multiple generations of hardware. Machines within a cluster are typically spread across 10-20 fault domains for high availability within a region. The following image shows the Azure Cosmos DB global distribution system topology:

Overall, global distribution in Cosmos DB allows you to distribute your data across multiple regions, ensuring low-latency access, high availability, and disaster recovery while also providing built-in compliance and data sovereignty capabilities.