SOA-C02 Networking and Content Delivery Practice Question

A company has deployed a web application across multiple Availability Zones using an Application Load Balancer. The application experiences increased latency during peak hours. Which action would be MOST effective in reducing latency?

⚠ Common exam trap

The trap is picking a configuration knob (health check, cross-zone, deregistration) that sounds like it improves performance but actually only affects availability or traffic distribution — the real fix for peak-load latency is adding capacity.

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

✓

Add more EC2 instances to the target group.

Adding more EC2 instances to the target group increases aggregate capacity, distributing the request load across more targets and reducing per-instance queueing and response time. During peak-hour latency spikes, horizontal scaling is the most direct and effective remedy because the bottleneck is typically compute or connection saturation on existing targets.

Answer analysis

Option-by-option breakdown

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

✓
Add more EC2 instances to the target group.
Why this is correct
Adding more EC2 instances to the target group horizontally scales web application capacity, allowing the ALB to distribute incoming requests across more compute resources. When latency is caused by CPU saturation, connection exhaustion, or thread-pool limits, this directly reduces per-instance load and therefore reduces queuing delay. It is the correct action because it addresses the root cause of latency under sustained traffic.
✗
Update the health check to use a more frequent interval.
Why it's wrong here
A more frequent health check interval does not lower request latency; its sole purpose is to detect unhealthy targets faster so the ALB can stop routing traffic to them. More frequent checks increase the monitoring overhead on both the ALB and the targets, and they do not affect the processing time for legitimate traffic. Latency is a function of request handling capacity, not health-check cadence.
✗
Enable cross-zone load balancing on the ALB.
Why it's wrong here
Cross-zone load balancing on an ALB is already enabled by default and evenly distributes traffic across all healthy targets in all Availability Zones. Even if it were disabled, enabling it would not reduce the time it takes to process a single request; it only improves distribution and prevents any single AZ from being overloaded. Latency improvements from cross-zone balancing would be indirect at best and are not a direct remedy for high per-request latency.
✗
Increase the deregistration delay for the target group.
Why it's wrong here
Increasing the deregistration delay prolongs the window during which in-flight requests can complete after a target is marked for deregistration, which helps maintain availability during rolling deployments. It does not reduce latency for ongoing traffic, and if the delay is excessive, it can actually keep over-loaded instances receiving requests longer. This setting is about graceful connection draining, not performance tuning.

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SOA-C02 Networking and Content Delivery Practice Question

Why each option matters

Option-by-option breakdown

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