SAA-C03 Design High-Performing Architectures Practice Question

Answer analysis

Option-by-option breakdown

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

• ✓

  Move all instances into a cluster placement group.

  Why this is correct

  Cluster placement groups pack instances closely together in a single Availability Zone, which minimizes network distance and improves latency consistency. This is the best placement strategy when the workload is highly chatty and needs very low jitter between nodes. It directly targets east-west performance.

• ✓

  Use instance families that provide high network bandwidth and support enhanced networking.

  Why this is correct

  Instance selection matters because network bandwidth and packet processing capability affect latency under heavy inter-node messaging. Choosing network-optimized or otherwise high-bandwidth families with enhanced networking reduces contention and improves message throughput. This complements the placement group choice and improves the cluster’s overall behavior.

• ✗

  Spread the instances across three Availability Zones for better fault tolerance.

  Why it's wrong here

  Spreading across AZs improves resilience, but it increases network distance and typically adds latency. The scenario is explicitly about minimizing jitter and latency for frequent east-west traffic within one AZ, so multi-AZ spread is the wrong optimization.

• ✗

  Front the nodes with an Application Load Balancer to balance the internal messages.

  Why it's wrong here

  An ALB is for HTTP/HTTPS application traffic, not for direct node-to-node messaging performance. It adds a layer that does not solve the underlying east-west latency issue. The workload needs closer physical placement and better networking, not a web load balancer.

• ✗

  Store the messages on EBS volumes so the nodes avoid network communication.

  Why it's wrong here

  EBS is block storage for persistent data, not a low-latency message bus. Writing messages to disk would add storage latency and does not create efficient inter-node communication. It also changes the workload architecture in an unsupported way for this requirement.