SOA-C02 Networking and Content Delivery Practice Question

A SysOps administrator is designing a highly available web application across multiple AWS regions. The application uses an Application Load Balancer in each region. Which TWO services can be used to route traffic to the closest regional load balancer based on latency?

⚠ Common exam trap

SOA-C02 often tests the distinction between latency-based routing and geoproximity routing — candidates may pick geoproximity thinking it means 'closest,' but it is geographic, not latency-based, and does not measure actual network performance.

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

✓

AWS Global Accelerator

Option A (AWS Global Accelerator) is correct because it uses the AWS global network and anycast IP addresses to route user traffic to the optimal regional endpoint based on latency and health, and it can front Application Load Balancers in multiple regions. Option D (Amazon Route 53 latency-based routing) is correct because it returns the regional record whose AWS Region has the lowest measured latency to the requesting resolver, directing users to the closest regional ALB. Option B (geoproximity routing) routes based on geographic location and optional bias, not measured network latency, so it does not meet the stated requirement. Option C (weighted routing) distributes traffic by assigned proportions regardless of latency, so it is not latency-based. Option E (CloudFront with origin groups) is for origin failover within a distribution and does not route to the closest regional load balancer by latency.

Answer analysis

Option-by-option breakdown

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

✓
AWS Global Accelerator
Why this is correct
AWS Global Accelerator routes traffic over the AWS global network to the endpoint with the lowest latency, using anycast IP addresses that direct users to the nearest edge location. This satisfies the requirement to reach the closest regional Application Load Balancer, unlike DNS-based routing which depends on resolver caching and TTL behaviour.
✗
Amazon Route 53 geoproximity routing
Why it's wrong here
Geoproximity routing biases traffic by geographic distance and bias values, not measured latency between users and endpoints. It suits shifting load toward or away from a region for expansion, whereas latency-based routing answers the closest-by-latency requirement.
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Amazon Route 53 weighted routing
Why it's wrong here
Weighted routing distributes traffic by assigned proportions, ignoring client location entirely. Latency-based routing, or geolocation routing, is the record type that resolves to the regional load balancer with the lowest measured latency for the requesting resolver.
✓
Amazon Route 53 latency-based routing
Why this is correct
Route 53 latency-based routing resolves DNS queries to the regional record with the lowest measured latency, directing users to the closest regional ALB. This satisfies the multi-region latency requirement, though DNS caching affects failover speed.
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Amazon CloudFront with origin groups
Why it's wrong here
CloudFront origin groups provide failover between origins for a distribution, not DNS-based selection of the closest regional load balancer. They suit resilience against origin failure, whereas latency-based routing records resolve users to the nearest region.

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SOA-C02 Networking and Content Delivery Practice Question

Why each option matters

Option-by-option breakdown

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