SAP-C02 Design for New Solutions Practice Question

A media company is building a video transcoding pipeline using AWS Elemental MediaConvert. The source videos are uploaded to an S3 bucket, and the transcoded outputs are stored in another S3 bucket. The company wants to trigger the transcoding job as soon as a new video is uploaded. The pipeline must handle high volumes of uploads and ensure that no upload is missed. Which solution is MOST reliable and scalable?

⚠ Common exam trap

The trap here is that candidates may overcomplicate the solution by adding intermediate services like SNS or SQS, thinking they improve reliability, when in fact the direct S3-to-Lambda integration is the most reliable and scalable for this specific trigger pattern, and additional components only introduce unnecessary complexity and potential failure points.

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

✓

Configure an S3 event notification to directly invoke an AWS Lambda function that starts the MediaConvert job.

S3 event notifications can directly invoke a Lambda function with minimal latency and no intermediate components, making it the simplest and most reliable way to trigger MediaConvert jobs for each upload. S3 event notifications are designed to deliver events with at-least-once delivery semantics, ensuring no upload is missed even under high volumes. This direct integration avoids additional failure points like SNS or SQS, which could introduce delays or require extra configuration for scaling.

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 an S3 event notification to directly invoke an AWS Lambda function that starts the MediaConvert job.
Why this is correct
This is a simple, reliable, and scalable event-driven pattern.
✗
Configure an S3 event notification to publish to an Amazon SNS topic, which triggers an AWS Lambda function that starts the MediaConvert job.
Why it's wrong here
SNS does not guarantee delivery ordering or deduplication, so under high-volume concurrent uploads, a Lambda function invoked by SNS could receive duplicate or out-of-order events, risking missed or redundant transcoding jobs. This option is tempting because SNS is a standard pub/sub service for fan-out patterns, and it would be correct if the requirement were to broadcast notifications to multiple subscribers without needing strict event sequencing or exactly-once processing.
✗
Use Amazon EventBridge to detect S3 PUT events and route them to a Lambda function.
Why it's wrong here
EventBridge is not the primary service for S3 event notifications; S3 event notifications are native.
✗
Configure an S3 event notification to send events to an Amazon SQS queue, and have a Lambda function poll the queue and start MediaConvert jobs.
Why it's wrong here
SQS adds polling overhead and complexity.

Quick reference

AWS S3 Storage Class Comparison

Storage Class	Min Duration	Retrieval	Use Case
S3 Standard	None	Immediate	Frequently accessed data
S3 Standard-IA	30 days	Immediate	Infrequent access, rapid retrieval
S3 One Zone-IA	30 days	Immediate	Non-critical infrequent data
S3 Intelligent-Tiering	None	Immediate–hours	Unknown or changing access patterns
S3 Glacier Instant	90 days	Milliseconds	Archive with instant retrieval
S3 Glacier Flexible	90 days	Minutes–hours	Archive, flexible retrieval
S3 Glacier Deep Archive	180 days	Hours	Long-term compliance archive

Go deeper

SAP-C02 Design for New Solutions Practice Question

Why each option matters

Option-by-option breakdown

AWS S3 Storage Class Comparison

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