ANS-C01 Network Implementation Practice Question
A company is implementing a network architecture for a critical application that requires ultra-low latency between two Amazon EC2 instances. The instances are launched in two different Availability Zones within the same AWS Region. The network engineer needs to ensure that traffic between the instances uses the lowest latency path possible. The instances are placed in a cluster placement group. The application uses TCP. The engineer has configured the security groups to allow all traffic between the instances. However, latency is higher than expected. What should the engineer do to reduce latency?
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
✓
Enable Elastic Network Adapter (ENA) and enhanced networking on both instances.
Elastic Network Adapter (ENA) with enhanced networking provides lower latency and higher throughput by offloading network processing to hardware. While the cluster placement group minimizes network distance, it does not guarantee the lowest latency without ENA. Option A is incorrect because instances in the same VPC already communicate via private IPs by default. Option C is incorrect because moving to the same AZ is not necessary and would reduce fault tolerance. Option D is incorrect because VPC peering does not improve latency within the same VPC.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Configure the instances to use their private IP addresses instead of public IPs for communication.
Why it's wrong here
Private IP is default; not the issue.
- ✓
Enable Elastic Network Adapter (ENA) and enhanced networking on both instances.
Why this is correct
ENA reduces latency by offloading network processing.
- ✗
Move the instances to the same subnet within the same Availability Zone.
Why it's wrong here
Already in cluster placement group; same AZ would help but not as much as ENA.
- ✗
Set up a VPC peering connection between the subnets in the two Availability Zones.
Why it's wrong here
Instances are in same VPC; peering unnecessary.
Go deeper
Related to this question
About these practice questions
This ANS-C01 question is part of Courseiva's 1,621-question bank — original exam-style content with full explanations and wrong-answer analysis, never real exam questions or exam dumps. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This ANS-C01 practice question is part of Courseiva's free Amazon Web Services certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the ANS-C01 exam.