What caused the sudden spike in latency for Vonage's Voice API calls in the North American region yesterday?

Introduction

The sudden spike in latency for Vonage's Voice API calls in the North American region yesterday is a critical issue that demands immediate attention and thorough analysis. As we delve into this problem, we'll follow a systematic approach to identify, validate, and address the root cause while considering both short-term fixes and long-term strategic implications.

Step 1

Clarifying Questions (3 minutes)

• Looking at the regional specificity, I'm wondering about network infrastructure. Has there been any recent changes to our CDN or server locations in North America?

Why it matters: Infrastructure changes could directly impact latency. Expected answer: No recent changes to infrastructure. Impact on approach: If there were changes, we'd focus on rollback or optimization.

• Considering the suddenness of the spike, I'm curious about traffic patterns. Did we see any unusual surge in call volume or user behavior yesterday?

Why it matters: Unexpected traffic spikes could overwhelm our systems. Expected answer: Normal traffic patterns observed. Impact on approach: If abnormal, we'd investigate capacity planning and load balancing.

• Thinking about system dependencies, have there been any updates to our Voice API or related services in the past week?

Why it matters: Recent updates could introduce bugs affecting latency. Expected answer: Minor update deployed two days ago. Impact on approach: If confirmed, we'd scrutinize the update for potential issues.

• Reflecting on external factors, were there any reported issues with major cloud providers or telecom carriers in North America yesterday?

Why it matters: External provider issues could cause widespread latency problems. Expected answer: No major reported issues. Impact on approach: If issues reported, we'd coordinate with providers for resolution.