Detailed Design of WhatsApp

Detailed design

The high-level design discussed in the previous lesson doesn’t answer the following questions:

• How is a communication channel created between clients and servers?

• How can the high-level design be scaled to support billions of users?

• How is the user’s data stored?

• How is the receiver identified to whom the message is delivered?

To answer all these questions, let’s dive deep into the high-level design and explore each component in detail. Let’s start with how users make connections with the chat servers.