Examkin

Question

Difficulty: MediumOptimizing Network Performance and Latency

A media streaming company hosts a high-throughput video processing pipeline in the `us-west-2` Region across two VPCs: an Ingestion VPC and a Processing VPC. The Ingestion VPC receives raw high-definition video feeds and stores them temporarily on Amazon EC2 instances. The Processing VPC hosts a cluster of GPU-accelerated EC2 instances that pull these video files for transcoding. Currently, all network traffic between the two VPCs routes through an AWS Transit Gateway. The application requires transferring files of up to 5050 GB with a minimum throughput of 1010 Gbps and the lowest possible latency. During peak events, the company observes packet fragmentation and throughput limits due to MTU constraints on the Transit Gateway path. The company also uses an Amazon Route 53 Private Hosted Zone (PHZ) named `video.internal` for service discovery, which is currently associated only with the Ingestion VPC. Which solution should a solutions architect implement to optimize network performance, maximize throughput, and maintain DNS resolution?

  1. Establish a VPC Peering connection directly between the Ingestion VPC and the Processing VPC. Configure VPC route tables to route traffic destined for the peer VPC CIDR through the peering connection, and enable jumbo frames (90019001 MTU) on the EC2 instances. Associate the Route 53 Private Hosted Zone `video.internal` with the Processing VPC.Answer
  2. B
    Establish a VPC Peering connection directly between the Ingestion VPC and the Processing VPC. Configure VPC route tables to route traffic destined for the peer VPC CIDR through the peering connection, and enable jumbo frames (90019001 MTU) on the EC2 instances. Do not modify the Route 53 Private Hosted Zone, as DNS resolution is automatically shared across peered VPCs.
  3. C
    Keep the existing Transit Gateway configuration, but deploy a Transit Gateway Connect attachment with GRE tunnels between the Ingestion VPC and the Processing VPC to support virtual routing. Associate the Route 53 Private Hosted Zone `video.internal` with the Processing VPC.
  4. D
    Deploy a NAT Gateway in a public subnet of the Ingestion VPC, and route all outgoing transcoding traffic from the Processing VPC to this NAT Gateway using Transit Gateway. Associate the Route 53 Private Hosted Zone `video.internal` with the Processing VPC.

Answer

Establish a VPC Peering connection directly between the Ingestion VPC and the Processing VPC, update VPC route tables to route peer traffic, enable jumbo frames (90019001 MTU), and associate the Route 53 Private Hosted Zone `video.internal` with the Processing VPC.
Establishing a VPC Peering connection directly between the two VPCs allows the configuration of jumbo frames (90019001 MTU) end-to-end, which reduces packet fragmentation and overhead. This optimizes throughput and latency compared to AWS Transit Gateway, which has an MTU limit of 85008500 bytes. Furthermore, the Route 53 Private Hosted Zone must be associated with the Processing VPC so that instances in it can resolve endpoints under `video.internal`.

Step-by-Step Solution

1
Analyze MTU limits on the paths.
AWS Transit Gateway limits the MTU size to 85008500 bytes for VPC attachments. VPC Peering supports jumbo frames up to 90019001 bytes MTU for traffic within the same region.
To avoid packet fragmentation for large file transfers, the path must support jumbo frames (90019001 MTU).
2
Establish the optimized network path.
Create a VPC Peering connection directly between the Ingestion VPC and the Processing VPC, update route tables to use the peering connection, and configure EC2 instances to use jumbo frames.
This bypasses Transit Gateway, reduces the network hop, and enables end-to-end 90019001 MTU.
3
Configure DNS resolution for the private domain.
Associate the Route 53 Private Hosted Zone `video.internal` with the Processing VPC.
Route 53 Private Hosted Zones are not transitively resolved across peered VPCs automatically; explicit association is required.

Key Concept

VPC Peering vs. Transit Gateway MTU support and Private Hosted Zone VPC association
Estimated Time:2m 0s
Rate this question

Topics

Optimizing Network Performance and Latency