Ref: https://learn.cantrill.io/courses/1820301/lectures/41301591

• Summary:
• Contents:

R53 Geoproximity Routing - Architecture

Diagram: https://github.com/acantril/aws-sa-associate-saac03/blob/main/1200-ROUTE53/00_LEARNINGAIDS/Route53GeoProximityRouting-1.png

• 🔧 Multiple records with the same host name. Each record has a geographic location and (optionally) a bias.
  • If resource is AWS internal → location specified with AWS region
    • e.g. us-east-1, ap-southeast-2…
  • If resource is external → location specified with coordinates (latitude + longitude)
  • When DNS query comes in, R53 returns the (geographically) closest record to the client
    • i.e. Routing is distance based
    • ‼️ The bias can artificially influence the proximity of records
• Bias = value that adjusts the size of the geographic area used to route traffic
  • + or - value → expand or shrink the geographic area
  • e.g. We have R53 records in UK and Australia. A customer from Saudi Arabia makes a DNS query.
    • Without bias → fetch UK resource because it's closer (6700km vs 10 000km)
    • Give UK a + bias and Australia a much bigger + bias → Saudi Arabia now under Australia radius, Australia records are returned (see diagram below)
• 💡 Very flexible routing type
  • Routing based on geographic proximity, can add bias to influence routing decisions