When should you choose WebSockets or Server-Sent Events (SSE)?

When should you choose WebSockets or Server-Sent Events (SSE)?

• A. They are deprecated in favor of polling.
• B. They are identical to traditional REST APIs.
• C. They enable real-time data delivery via open connections for push updates.
• D. They are best used for simple request-response interactions.

Answer: (C)

Real-time data delivery relies on an open, persistent connection that lets the server push updates to the client as soon as they happen. WebSockets give you a continuous, two-way channel where either side can send messages at any time. Server-Sent Events create a long-lived, server-to-client stream over HTTP, which lets the server push updates to the client automatically. Both are built for push-based updates rather than the usual request/response pattern of REST. You’d choose them whenever your app needs live data—think dashboards that refresh in real time, chat, live feeds, or notifications. If you need true bidirectional communication (client and server talking back and forth), go with WebSockets. If you only need the server to push updates to clients and keep things simple, SSE can be a lighter option. They’re not deprecated and they’re not the same as traditional REST polling or short-lived requests.

Real-time data delivery relies on an open, persistent connection that lets the server push updates to the client as soon as they happen. WebSockets give you a continuous, two-way channel where either side can send messages at any time. Server-Sent Events create a long-lived, server-to-client stream over HTTP, which lets the server push updates to the client automatically. Both are built for push-based updates rather than the usual request/response pattern of REST.

You’d choose them whenever your app needs live data—think dashboards that refresh in real time, chat, live feeds, or notifications. If you need true bidirectional communication (client and server talking back and forth), go with WebSockets. If you only need the server to push updates to clients and keep things simple, SSE can be a lighter option. They’re not deprecated and they’re not the same as traditional REST polling or short-lived requests.