When managing your applications and services in Amazon Web Services (AWS), you often need to route traffic to different endpoints based on users’ geographical locations. This is where routing policies like geolocation and geoproximity come into play. In this blog, we’ll demystify these two routing policies.

Geolocation Routing Policy

Geolocation routing is like serving different flavors of ice cream based on where your customers are in the world. With this policy, you can route traffic to specific endpoints based on the geographic locations of your users. Here’s how it works:

1. Regions and Countries: You can specify which AWS regions or even entire countries you want to target with specific routing rules. For example, you might send users from Europe to a data center in Frankfurt and users from Asia to a data center in Tokyo.
2. Default Route: Don’t forget about the default route! This is the endpoint users will be sent to if they don’t match any of your defined geolocation rules.
3. Use Cases: Geolocation routing is handy for content delivery networks (CDNs), where you want to serve content from the nearest data center to reduce latency. It’s also useful for complying with data sovereignty laws by ensuring data stays within certain borders.

Geoproximity Routing Policy

Geoproximity routing is a bit more sophisticated. Think of it as sending your packages to the nearest post office for delivery. This policy routes traffic based on the proximity of your users to your AWS resources. Here’s a simple breakdown:

1. Geographic Regions: You define geographic regions, such as a city or a state, where your AWS resources are located. These could be your data centers or endpoints.
2. Routing Bias: You can set a “routing bias” to determine how close a user has to be to a region to be routed there. For example, you might set a high bias to send users to the nearest region unless it’s significantly farther away.
3. Use Cases: Geoproximity routing is useful when you want to optimize latency and route users to the nearest available resources. It’s also handy for ensuring failover in case one region experiences issues.

Which One to Choose?

So, when do you use each routing policy? It depends on your specific use case.

• Geolocation routing is perfect when you want to serve content or applications to users based on their country or region, or when you need to comply with data location regulations.
• Geoproximity routing is ideal when you have multiple resources in different locations and want to route users to the nearest aws available resource for better performance.

In a nutshell, geolocation is like sending regional postcards, while geoproximity is more like dispatching packages from the closest post office. Each has its unique strengths, so choose the one that best suits your AWS routing needs.