Comparison: HTTP vs WebSocket vs REST
When designing APIs or communication protocols for applications, developers often choose between HTTP, WebSocket, and REST based on use case, efficiency, and scalability. Below is a detailed comparison:
📌 Quick Overview
| Feature | HTTP | WebSocket | REST |
|----------|---------|--------------|---------|
| Type | Request-Response | Persistent, Full-Duplex | Request-Response |
| Communication Model | Client sends request, server responds | Real-time bidirectional communication | Stateless API using HTTP |
| Connection | Opens & closes with each request | Persistent connection | Stateless (new connection per request) |
| Performance | Latency due to handshaking | Low latency, efficient | Moderate performance |
| Data Format | Plain text, JSON, XML | JSON, Binary, Text | JSON, XML, HTML |
| Best Use Cases | Web pages, file downloads | Chat apps, live feeds, gaming | APIs, microservices |
| Security | HTTPS (SSL/TLS) | WSS (SSL/TLS) | HTTPS (SSL/TLS) |
| Scalability | High but may require caching | Requires WebSocket support | Highly scalable with caching |
1️⃣ What is HTTP?
HTTP (Hypertext Transfer Protocol) is a request-response protocol used for communication between clients (browsers, mobile apps, APIs) and servers.
✅ Key Features of HTTP
- Stateless → Every request is independent and does not retain session state.
- Client-initiated → The client always sends a request, and the server responds.
- Uses TCP → Runs over port 80 (HTTP) or port 443 (HTTPS).
- Text-based format → Uses JSON, XML, or HTML for requests and responses.
📌 When to Use HTTP?
✅ Web pages, form submissions.
✅ RESTful APIs and Microservices.
✅ File downloads and Content Delivery Networks (CDNs).
2️⃣ What is WebSocket?
WebSocket is a full-duplex, bidirectional protocol that allows real-time communication between clients and servers.
✅ Key Features of WebSocket
- Persistent connection → The connection remains open after handshake.
- Low latency → Ideal for real-time applications.
- Push-capable → The server can send messages without waiting for a request.
- Uses TCP (Port 80/443) → Upgrades HTTP to ws:// or wss://.
📌 When to Use WebSocket?
✅ Live chat applications (WhatsApp, Slack).
✅ Stock market tickers & financial dashboards.
✅ Online gaming (real-time player updates).
✅ Live notifications and collaborative apps.
3️⃣ What is REST?
REST (Representational State Transfer) is an architectural style for designing web APIs that communicate over HTTP.
✅ Key Features of REST
- Stateless → Each request from a client contains all necessary information.
- Standardized methods → Uses GET, POST, PUT, DELETE, PATCH.
- Scalable & flexible → Can be cached and used with load balancers.
- Uses JSON/XML → Common for web APIs.
📌 When to Use REST?
✅ Web applications (CRUD operations).
✅ Mobile apps consuming backend APIs.
✅ Microservices architecture (communication between services).
4️⃣ Detailed Comparison Table: HTTP vs WebSocket vs REST
| Feature | HTTP | WebSocket | REST |
|---------|---------|--------------|---------|
| Communication Type | Client sends request, server responds | Persistent, real-time, bidirectional | Stateless, request-response |
| State Management | Stateless | Stateful | Stateless |
| Connection Type | New connection for each request | Persistent connection | New connection per request |
| Latency | High (handshake each time) | Low (persistent connection) | Moderate |
| Data Format | JSON, XML, HTML | JSON, Binary, Text | JSON, XML, HTML |
| Real-Time Capability | No | Yes | No |
| Server Push Capable? | No | Yes | No |
| Ideal Use Cases | Static web pages, APIs | Live chat, gaming, notifications | Web & mobile app backends, microservices |
| Security | HTTPS (TLS/SSL) | WSS (TLS/SSL) | HTTPS (TLS/SSL) |
| Scalability | High | Moderate | High |
| Port | 80/443 (HTTP/HTTPS) | 80/443 (ws:// / wss://) | 80/443 (HTTP/HTTPS) |
5️⃣ Use Case-Based Recommendations
| Use Case | Recommended Protocol |
|----------|------------------|
| Static website content | HTTP |
| API for mobile/web apps | REST over HTTP |
| Live chat/messaging apps | WebSocket |
| Stock market updates | WebSocket |
| IoT devices (real-time data) | WebSocket |
| CRUD operations (database APIs) | REST |
| Microservices communication | REST over HTTP |
| Multiplayer online games | WebSocket |
6️⃣ Summary & Conclusion
| Criteria | Best Choice |
|-------------|--------------|
| Best for Static Content Delivery | HTTP |
| Best for API Communication | REST |
| Best for Real-Time Communication | WebSocket |
🚀 Key Takeaways
- Use HTTP for general web communication (e.g., website browsing).
- Use WebSockets for real-time applications (e.g., chat apps, live notifications).
- Use REST for scalable web APIs (e.g., backend services).
