Why has Clickatell's SMS API seen a 15% drop in message delivery rates over the past week?

Introduction

Clickatell's SMS API has experienced a 15% drop in message delivery rates over the past week, indicating a significant issue that requires immediate attention. This analysis will systematically identify, validate, and address the root cause while considering both short-term fixes and long-term implications for the product.

Step 1

Clarifying Questions (3 minutes)

• Looking at the timing, I'm thinking this could be a recent change. Has there been any system update or configuration change in the past 10 days?

Why it matters: Recent changes often correlate with performance issues. Expected answer: Yes, there was a minor update to the API gateway. Impact on approach: If confirmed, we'd focus on the update's impact on message delivery.

• Considering user segments, I'm curious about the distribution. Is the 15% drop uniform across all customers or concentrated in specific segments?

Why it matters: Helps identify if the issue is systemic or segment-specific. Expected answer: The drop is more pronounced among enterprise customers. Impact on approach: We'd investigate enterprise-specific integrations or usage patterns.

• Thinking about external factors, have there been any significant changes in carrier relationships or policies recently?

Why it matters: Carrier issues can directly impact SMS delivery rates. Expected answer: No major changes reported with carriers. Impact on approach: We'd shift focus to internal systems and processes.

• Regarding performance metrics, has there been any change in how we measure or define "delivery rates" in the past month?

Why it matters: Ensures we're comparing apples to apples in our analysis. Expected answer: No changes to the metric definition or measurement process. Impact on approach: Confirms the issue is with actual performance, not measurement.