AWS Certified Solutions Architect – Associate (SAA-C02) — Question 735

A company is deploying an application that processes streaming data in near-real time. The company plans to use Amazon EC2 instances for the workload. The network architecture must be configurable to provide the lowest possible latency between nodes.
Which combination of network solutions will meet these requirements? (Choose two.)

Answer options

• A. Place the EC2 instances in multiple VPCs, and configure VPC peering.
• B. Run the EC2 instances in a spread placement group.
• C. Attach an Elastic Fabric Adapter (EFA) to each EC2 instance.
• D. Use Amazon Elastic Block Store (Amazon EBS) optimized instance types.

Correct answer: B, C

Explanation

Attaching an Elastic Fabric Adapter (EFA) to EC2 instances provides high-performance, low-latency inter-node communication by bypassing the operating system kernel. Utilizing placement groups helps manage the physical placement of instances to optimize network performance, whereas VPC peering adds network hops and EBS optimization only improves storage-related I/O rather than node-to-node network latency.