Cloudflare

Global network delivering content delivery, security, and performance services. Cloudflare is essential infrastructure for modern web applications, offering free and paid tiers.

Core Services

CDN (Content Delivery Network)

• Global Network: 300+ data centers worldwide
• Automatic Caching: Static content cached at edge
• Cache Control: Flexible cache rules and purging
• Image Optimization: Polish and Mirage for images
• HTTP/3 & QUIC: Latest protocols enabled

DNS

• Authoritative DNS: Ultra-fast DNS resolution
• Free DNS: Managed DNS for any domain
• DNSSEC: Security extensions enabled
• DNS Analytics: Query insights and analytics
• 1.1.1.1: Public DNS resolver (privacy-focused)

Security

• DDoS Protection: Unlimited DDoS mitigation on all plans
• WAF (Web Application Firewall): Protection against OWASP Top 10
• SSL/TLS: Free SSL certificates with auto-renewal
• Bot Management: Detect and mitigate malicious bots
• Rate Limiting: Protect against API abuse
• Zero Trust: Network access control and ZTNA

Performance

• Argo Smart Routing: Optimize routing for 30% faster
• Load Balancing: Global and health-checked load balancing
• Workers: Serverless functions at the edge
• Pages: JAMstack deployment platform
• R2: S3-compatible object storage (no egress fees)
• KV: Key-value storage at the edge

Cloudflare Workers

Run JavaScript at the edge:

addEventListener('fetch', event => {
  event.respondWith(handleRequest(event.request))
})

async function handleRequest(request) {
  // Your logic here
  return new Response('Hello from the edge!', {
    headers: { 'content-type': 'text/plain' },
  })
}

Use Cases

• API gateways
• A/B testing
• Geo-routing
• Authentication
• HTML rewriting
• Caching logic

Cloudflare Pages

Deploy JAMstack sites:

# Deploy with Wrangler CLI
npx wrangler pages publish dist

# Or connect Git repo for auto-deployment
# Supports: Next.js, React, Vue, Svelte, Hugo, etc.

Features:

• Unlimited bandwidth on free plan
• Automatic deployments from Git
• Preview deployments for PRs
• Custom domains with SSL
• Edge functions via Workers

Cloudflare R2

S3-compatible storage without egress fees:

// Upload to R2
await env.MY_BUCKET.put('file.txt', 'content')

// Read from R2
const object = await env.MY_BUCKET.get('file.txt')
const text = await object.text()

Pricing

Free Plan

• Unlimited DDoS mitigation
• Global CDN
• Free SSL certificates
• Shared SSL
• 100k Workers requests/day
• Unlimited Pages bandwidth

Pro ($20/month)

• Everything in Free
• WAF
• Image optimization
• 10M Workers requests/month
• Mobile optimization
• 20 custom page rules

Business ($200/month)

• Everything in Pro
• Custom SSL certificates
• Advanced DDoS
• PCI compliance
• 100M Workers requests/month
• Priority support

Enterprise (Custom)

• Everything in Business
• 24/7/365 phone support
• Guaranteed uptime SLA
• Advanced security features
• Dedicated solutions engineer

Common Configurations

DNS Setup

1. Add domain to Cloudflare
2. Update nameservers at registrar
3. Configure DNS records
4. Enable proxy (orange cloud) for protection

SSL/TLS Modes

• Flexible: Client↔CF encrypted, CF↔Origin unencrypted
• Full: Encrypted end-to-end (self-signed OK)
• Full (Strict): Encrypted with valid certificate
• Strict (Custom): Custom certificate validation

Page Rules

URL Pattern: example.com/api/*
Settings:
- Cache Level: Bypass
- Security Level: High
- Rate Limit: 100 req/min

Security Features

Firewall Rules

(http.request.uri.path contains "/admin" and ip.src ne 1.2.3.4)

Transform Rules

Modify headers, URLs, or responses at the edge.

Rate Limiting

// Block if > 100 requests/minute from single IP
if (rate > 100/60s) {
  return new Response('Rate limited', { status: 429 })
}

Analytics

• Traffic analytics
• Security insights
• Performance metrics
• Worker analytics
• DNS analytics
• Real-time threat monitoring

Best For

• Startups: Free plan great for getting started
• SaaS Products: DDoS protection and global CDN
• APIs: Workers for edge computing
• Static Sites: Pages for JAMstack deployment
• Security-Conscious: WAF and DDoS protection
• Global Applications: Worldwide presence needed

Integration

Terraform

resource "cloudflare_zone" "example" {
  zone = "example.com"
}

resource "cloudflare_record" "www" {
  zone_id = cloudflare_zone.example.id
  name    = "www"
  value   = "192.0.2.1"
  type    = "A"
  proxied = true
}

API

curl -X GET "https://api.cloudflare.com/client/v4/zones" \
  -H "Authorization: Bearer YOUR_API_TOKEN"

Pro Tips

• Always use "Full (Strict)" SSL mode in production
• Enable "Always Use HTTPS" in SSL/TLS settings
• Use Page Rules strategically (limited on free plan)
• Workers can replace many backend services
• R2 saves massive costs vs S3 for high-bandwidth use
• Cache everything possible with proper cache headers
• Use Transform Rules instead of Workers when possible
• Enable DNSSEC for additional security

Cloudflare has become essential infrastructure for the modern web, offering enterprise-grade security and performance with a generous free tier that's perfect for indie developers and startups.