Design URL Shortening Infrastructure for IoT devices

Last updated: April 7, 2026

Quick Overview

Design a real-time url shortening system that handles millions of requests. Discuss trade-offs in consistency, availability, and performance.

Confluent
System Design
Software Engineer
Confluent
April 7, 2026
Software Engineer
System Design Round
System Design
Medium

31

11

372 solved


Design a real-time url shortening system that handles millions of requests. Discuss trade-offs in consistency, availability, and performance.

This is a common system design question asked during System Design Round at Confluent. The interviewer expects you to demonstrate your ability to design large-scale distributed systems, make well-reasoned trade-offs, and communicate your thought process clearly. Confluent values engineers who can think about scalability from day one.

What the Interviewer Expects
  • Systematically gather requirements and estimate capacity (QPS, storage, bandwidth)
  • Design a scalable architecture with clear component responsibilities
  • Make well-reasoned database and caching decisions with trade-off analysis
  • Address consistency vs availability trade-offs specific to the use case
  • Discuss partitioning strategy, replication, and data modeling
  • Cover failure handling, monitoring, and alerting strategies
Key Topics to Cover
Caching strategies (local, distributed, CDN)
API design and rate limiting
High-level architecture and component design
Security and authentication
How to Approach This
  1. Start by clarifying functional and non-functional requirements with the interviewer.
  2. Estimate the scale: QPS, storage, bandwidth. This drives your design decisions.
  3. Draw a high-level architecture first, then deep dive into 1-2 critical components.
  4. Discuss trade-offs explicitly (e.g., consistency vs availability, SQL vs NoSQL).
  5. Address failure scenarios, monitoring, and how the system handles 10x traffic spikes.
Possible Follow-up Questions
  • What happens if one of your database nodes goes down?
  • What would the deployment pipeline look like for this system?
  • How do you ensure data consistency across multiple services?
  • How would you handle schema migrations with zero downtime?
Practice a Similar Problem on Codemia

Solve a related problem with our interactive workspace, get AI feedback, and view detailed solutions.

Solve on Codemia
Sample Answer
Requirements
  • Functional Requirements:
    1. Generate short URLs for long URLs provided by IoT devices.
    2. Redirect requests from short URLs to their original long URLs in real-time.
    3. Allow users t...
Capacity Estimation
  • Assumptions:
    1. There are 1 million IoT devices sending requests to shorten URLs.
    2. Each device sends 10 requests per minute.
    3. Peak load is expected to be 10x average load.

-...


Submit Your Answer
Markdown supported

Related Questions