SOA-C02 Networking and Content Delivery Practice Question

A company hosts a web application on Amazon EC2 instances in two AWS regions: us-east-1 and eu-west-1. The application is behind an Application Load Balancer (ALB) in each region. The SysOps administrator wants to direct users to the region that provides the lowest latency, automatically routing traffic away from a region if it becomes unhealthy. Which Amazon Route 53 routing policy should be used?

⚠ Common exam trap

Candidates often confuse Geolocation routing with Latency routing, assuming geographic proximity equals low latency, but Geolocation routing does not measure actual network performance and lacks automatic health-based rerouting without additional failover records.

Answer choices

Why each option matters

Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.

Correct answer & explanation

✓

Latency routing

Latency routing (B) is correct because it directs users to the region with the lowest network latency based on real-time measurements between the user and the AWS endpoints. When a region becomes unhealthy, Route 53 automatically stops routing traffic to that region's ALB, ensuring failover to the next lowest-latency healthy region. This meets the requirement of both low-latency and automatic health-based rerouting.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

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Geolocation routing
Why it's wrong here
Geolocation routing bases its decision on the source IP address of the DNS query, mapping the requester's continent, country, or state to the endpoint that you have associated with that geography. It does not account for the actual network latency or current path conditions between the user and the available AWS regions. Because it is static per location, it cannot automatically shift traffic to another region if the designated region's ALB becomes unhealthy or if a different region happens to offer a lower latency at that moment.
✓
Latency routing
Why this is correct
Latency routing uses measurements of latency between AWS regions and the user to direct traffic to the region with the lowest latency. When health checks are attached to the ALBs, latency routing automatically avoids unhealthy endpoints by excluding them from responses.
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Weighted routing
Why it's wrong here
Weighted routing controls the proportion of traffic sent to each endpoint by assigning each record a relative weight, and Route 53 selects one record at random with probability proportional to that weight. It is designed for scenarios like A/B testing or gradual deployments, not for performance optimization. While associating health checks allows Route 53 to stop sending traffic to a failed endpoint, weighted routing never evaluates latency between users and regions, so it cannot ensure that users are directed to the region with the lowest current response time.
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Failover routing
Why it's wrong here
Failover routing implements an active-passive architecture where Route 53 normally sends all traffic to the designated primary record, and only switches to the secondary record when the primary's health check fails. This provides reliable disaster recovery but completely ignores performance, so a user who is geographically close to the secondary region still gets routed to the primary region as long as it is healthy. It cannot choose the lowest-latency endpoint on a per-request basis, making it unsuitable for the stated goal of optimizing latency across two active regions.

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SOA-C02 Networking and Content Delivery Practice Question

Why each option matters

Option-by-option breakdown

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