How Cloudflare works

More than just Content Delivery (CDN) services, customers rely on the Cloudflare® global network to enhance security, performance, and reliability of anything connected to the Internet. Cloudflare doesn’t require additional hardware, software, or changes to your code.

The following graphic illustrates how Cloudflare works to protect your site against malicious traffic:

Security

Cloudflare stops malicious traffic before it reaches your origin web server. Cloudflare analyzes potential threats in visitor requests based on several characteristics:

• Visitor’s IP address
• Requested resources
• Requested payload and frequency
• Customer-defined firewall rules

A Domain Name Service (DNS) lookup or ping of a proxied Cloudflare subdomain returns the Cloudflare IP addresses. Cloudflare masks your origin IP address for proxied (orange-clouded) DNS records so attackers cannot bypass Cloudflare and directly attack your origin web server.

Performance

Cloudflare optimizes the delivery of website resources for your visitors. Cloudflare’s data centers server your website’s static resources and ask your origin web server for dynamic content. Cloudflare’s global network provides a faster route from your site visitors to our data centers than would be available to a visitor directly requesting your site. Even with Cloudflare between your website and your visitors, resource requests arrive at your visitor sooner.

Reliability

Cloudflare’s globally-distributed anycast network routes visitor requests to the nearest Cloudflare data center. Cloudflare-distributed DNS responds to website visitors with Cloudflare IP addresses for traffic that you proxy to Cloudflare. This distribution also provides security by hiding the specific IP address of your origin web server.

Cloudflare-proxied domains share IP addresses from a pool that belongs to the Cloudflare network. As a result, Cloudflare does not offer dedicated or exclusive IP addresses.