Network Throttling / Rate Limiting System Design

Problem Overview

Design a network traffic throttling system for a cloud/datacenter environment. The system must handle two distinct traffic directions: 1. Outgoing (egress) traffic: Throttle outbound traffic originating from VMs/hosts. The expected approach is an on-host proxy (a throttler service co-located on the host) that monitors outgoing traffic per VM. When bandwidth…

• 3 candidate-reported follow-ups — the exact probes interviewers asked, with the trigger for each
• The rest of the problem statement — full requirements, constraints, and edge cases
• Approach and trade-offs — what passing candidates did, and the mistakes that sink people