Software-Engineering

HTTP/1.1 vs HTTP/2 Performance Comparison

This project demonstrates the performance differences between HTTP/1.1 and HTTP/2 protocols in Node.js.

Project Details

• Node.js Version: 14+
• Dependencies: Built-in Node.js modules (http, http2, fs)

Project Structure

.
├── http1.js           # HTTP/1.1 server implementation
├── http2.js           # HTTP/2 server implementation
├── cert.pem          # SSL certificate for HTTP/2
├── key.pem           # SSL private key for HTTP/2
└── README.md         # This file

Concept Overview

HTTP/1.1 vs HTTP/2

HTTP/1.1 is the traditional protocol that:

• Uses one request per connection
• Requires multiple connections for parallel requests
• Has head-of-line blocking issues

HTTP/2 is the modern protocol that:

• Multiplexes multiple requests over a single connection
• Uses binary framing instead of text
• Supports server push and header compression
• Eliminates head-of-line blocking

Why HTTP/2?

1. Performance: Better resource utilization with multiplexing
2. Efficiency: Header compression and binary protocol
3. Modern Web: Required for modern web features

Setup

Prerequisites

• Node.js (v14 or higher)
• OpenSSL (for generating certificates, if needed)

Generate SSL Certificates (if not present)

# Generate private key
openssl genrsa -out key.pem 2048

# Generate certificate
openssl req -new -x509 -key key.pem -out cert.pem -days 365

Usage

Start HTTP/1.1 Server

node http1.js

Server starts on port 3000.

Start HTTP/2 Server

node http2.js

Server starts on port 3443 (HTTPS).

Testing

HTTP/1.1 Endpoints

• GET / - Fast response
• GET /slow - Slow response (5 second delay)

HTTP/2 Endpoints

• GET / - Fast response
• GET /slow - Slow response (5 second delay)

Browser Testing

HTTP/1.1:

http://localhost:3000/
http://localhost:3000/slow

HTTP/2:

https://localhost:3443/
https://localhost:3443/slow

Note: For HTTP/2, your browser will show a security warning since we’re using a self-signed certificate. Click “Advanced” and “Proceed to localhost (unsafe)” to continue.

Load Testing

You can use tools like Apache Bench or curl to test performance:

# Test HTTP/1.1
curl http://localhost:3000/

# Test HTTP/2
curl -k https://localhost:3443/

Expected Behavior

Both servers implement the same logic:

• Fast responses return immediately
• Slow responses have a 5-second delay

The key difference is in how the protocols handle multiple concurrent requests:

• HTTP/1.1 may block other requests during slow responses
• HTTP/2 can handle multiple requests simultaneously over the same connection

Code Explanation

HTTP/1.1 Server (http1.js)

const http = require("http");

http.createServer((req, res) => {
    if (req.url === "/slow") {
        setTimeout(() => {
            res.end("SLOW RESPONSE");
        }, 5000);
    } else {
        res.end("FAST RESPONSE");
    }
}).listen(3000, () => {
    console.log("HTTP/1.1 server on port 3000");
});

HTTP/2 Server (http2.js)

const http2 = require("http2");
const fs = require("fs");

const server = http2.createSecureServer({
  key: fs.readFileSync("key.pem"),
  cert: fs.readFileSync("cert.pem"),
});

server.on("stream", (stream, headers) => {
  const path = headers[":path"];

  if (path === "/slow") {
    setTimeout(() => {
      stream.end("SLOW H2");
    }, 5000);
  } else {
    stream.end("FAST H2");
  }
});

server.listen(3443, () => {
  console.log("HTTP/2 server on 3443");
});

Key Differences

Feature	HTTP/1.1	HTTP/2
Protocol	Text-based	Binary
Connections	Multiple	Single
Multiplexing	No	Yes
Header Compression	No	Yes
Server Push	No	Yes
Security	Optional (HTTPS)	Required (TLS)

Cleanup

Stop the servers with Ctrl+C in their respective terminals.

Notes

• HTTP/2 requires HTTPS/TLS
• Self-signed certificates are used for demo purposes
• In production, use proper CA-signed certificates
• HTTP/2 is automatically negotiated by modern browsers