AWS Certified Advanced Networking – Specialty (ANS-C01)Network ImplementationMedium
A company is deploying a new containerized application that requires very high network throughput and low latency between its services. These services are deployed as EC2 instances within a single Availability Zone (AZ) in a private subnet. The application also needs to ensure that the instances are physically located close to each other to minimize inter-instance communication latency. Which placement strategy should the network engineer use for these EC2 instances?
- ADedicated Hosts
- BCluster Placement Group
- CSpread Placement Group
- DPartition Placement Group
Show answer & explanationAnswer & explanation
Correct answer: B. Cluster Placement Group
A Cluster Placement Group packs instances close together inside an Availability Zone, achieving high network throughput and low-latency communication. This is ideal for applications that require intensive inter-instance networking performance.
Why the other options are wrong
- A. Dedicated Hosts provide physical server capacity dedicated to your use, but do not inherently guarantee low-latency placement of instances relative to each other within the host or across hosts.
- C. Spread Placement Groups place instances on distinct underlying hardware to reduce correlated failures, which is opposite to the low-latency requirement.
- D. Partition Placement Groups divide instances into logical partitions to avoid correlated failures across partitions, not for low-latency inter-instance communication.
Cluster Placement Group
An EC2 placement strategy that groups instances logically within a single Availability Zone to achieve high network throughput and low-latency communication.
- Instances packed closely together
- Highest inter-instance network performance
- Must be within a single Availability Zone
- Suitable for HPC, big data, and tightly coupled applications
Memory trick: Cluster for Close, Spread for Separate, Partition for Parts.