What is Cloudflare? How CDNs, DNS, and DDoS protection work together

Key takeaways

• Cloudflare is a cloud platform that improves website speed, security, and reliability.
• It works by sitting between your visitors and your server as a reverse proxy.
• Cloudflare can cache content, manage DNS, filter malicious traffic, and add tools.
• It can help a lot, but it does not replace the need for strong hosting underneath it.

Cloudflare is a global cloud platform that helps websites, applications, and networks load faster, stay available, and handle more threats before they reach the origin server. It combines a content delivery network, DNS, reverse proxy services, security tools, and edge services into one layer that sits in front of your site.

Cloudflare operates from hundreds of data centers around the world and handles a meaningful share of internet traffic. If you run a website, Cloudflare can shape how visitors experience your pages, how quickly content loads, how much attack traffic reaches your server, and how much work your origin has to do.

How Cloudflare works

Cloudflare works as a reverse proxy. It sits between your visitors and your origin server, receives requests first, and then decides how to handle them. In some cases, it can respond from its own network. In others, it forwards the request to your origin server.

Cloudflare also handles DNS. The DNS system translates your domain name into an IP address so browsers know where to connect. In a standard Cloudflare setup, Cloudflare becomes your domain’s nameserver, which means DNS resolution and traffic proxying both pass through its network.

Because traffic passes through Cloudflare first, it can filter malicious requests, apply SSL settings, inspect traffic patterns, and optimize how requests reach your origin. That visibility is what makes Cloudflare’s speed and security features possible.

Cloudflare sits on top of your hosting, not in place of it. If your origin server is slow, overloaded, or poorly configured, Cloudflare can help in some cases, but it cannot turn weak hosting into strong infrastructure.

Cloudflare CDN

One of the main ways Cloudflare improves performance is through its content delivery network, or CDN. It uses a global network of data centers to deliver static assets like images, CSS, JavaScript, and other files from locations closer to visitors.

It does that through caching. When a visitor requests a page, Cloudflare checks whether that content is already available on a nearby edge server. If it is, Cloudflare serves it from there. If it is not, Cloudflare fetches it from the origin and may store it for future requests.

This lowers latency and reduces server load. Visitors can load content faster, and your origin has fewer repeated requests to process.

Caching also has tradeoffs. Static files are usually a good fit, but highly dynamic content needs more careful handling. If your content changes often, aggressive caching can serve stale inventory, stale dashboards, or outdated user-facing data. Cache-control directives help here, since you can control how long Cloudflare keeps certain resources and bypass caching where fresh content matters most.

Cloudflare security services

Cloudflare is widely used for security because it sits in front of the origin and can filter bad traffic before it reaches your infrastructure.  That includes DDoS protection, WAF features on paid plans, and SSL or TLS support.

DDoS protection

Since all traffic to your website first passes through the Cloudflare network, malicious traffic such as DDoS attacks can be detected, filtered, or rerouted without ever reaching your server in the first place. This helps protect the origin from being overwhelmed by large volumes of junk traffic.

Web application firewall

A web application firewall, or WAF, is designed to block common web exploits such as SQL injection, cross-site scripting, and other malicious request patterns before they hit the application. Cloudflare positions WAF features as part of its paid application security plans.

SSL and TLS

Cloudflare automatically provides SSL on proxied domains, which helps visitors access the site over HTTPS.  That can simplify setup, especially for site owners who want encrypted connections without managing every certificate manually.

Traffic filtering and security levels

Cloudflare also offers traffic filtering controls and features like Under Attack Mode. When enabled, Cloudflare can challenge suspicious visitors before they reach the site. That can help during active attack periods, but it can also add friction if used too broadly.

Zero Trust and edge computing

Cloudflare is not limited to CDN and DNS. It also offers Zero Trust tools and edge computing services.

Cloudflare Access is part of its Zero Trust lineup. It protects internal resources by securing, authenticating, and monitoring access per user and per application. In practice, that means organizations can use identity-based access controls instead of exposing internal tools through a traditional VPN-only model.

Cloudflare Workers is its edge computing platform. It lets developers run serverless code close to users instead of routing every request back to a central server. That can reduce latency for certain workloads and support use cases like request handling, personalization, and lightweight application logic at the edge.

For someone searching “what is Cloudflare,” these services aren’t the first thing to understand, but they do matter because they show how Cloudflare has expanded beyond CDN and DNS into security and application delivery.

Additional Cloudflare tools

Cloudflare includes a wider set of tools beyond CDN, DNS, and basic security.

• Bot management. Cloudflare can evaluate traffic patterns and separate real visitors from many forms of automated traffic. That can help reduce scraping, spam, abusive bots, and some low-quality automated requests.
• Image and performance optimization. Cloudflare offers performance-focused add-ons and optimizations that can reduce transfer costs and improve delivery speed, especially when paired with caching and route optimization.
• Load balancing. Cloudflare Load Balancing distributes traffic across local or global origins, includes health checks, and supports failover. This can help keep applications reachable when one origin has trouble.
• Analytics and reporting. Cloudflare also gives site owners visibility into traffic, requests, performance, and security events. That reporting can help identify spikes, suspicious activity, and caching behavior more quickly than working from origin logs alone.

Cloudflare pricing and plans

Cloudflare offers three main plans for websites: Free, Pro, and Business. The right choice depends on how much security, performance, and control your site needs. 

Some Cloudflare features are still sold separately rather than bundled into the base plans. Load balancing, advanced certificate options, and access controls are examples.

When Cloudflare helps and when it might not

Cloudflare can be a strong fit when:

• Your audience is geographically spread out
• Your site gets traffic spikes
• You need help absorbing attack traffic
• You serve a lot of static assets
• You want a simpler DNS and CDN layer in front of the site

It may add less value, or more complexity, when:

• Your audience is concentrated in one location close to the origin
• Most of your content is highly dynamic
• You need very tight control over DNS behavior
• Your real bottleneck is weak origin hosting, not edge delivery
• Coaching introduces freshness problems that outweigh the speed gains

This is where honest expectations matter. Cloudflare can improve speed, reduce load, and add protection, but it does not remove the need for a fast origin, a healthy application stack, and well-managed infrastructure behind it.

How to get started with Cloudflare

Setting up a Cloudflare account is free and easy to do. In most cases, the setup process looks like this:

1. Create a Cloudflare account.
2. Add your domain.
3. Review and import DNS records.
4. Update your domain’s nameservers at the registrar.
5. Wait for DNS to update.
6. Configure caching, SSL, and security settings.

The main requirement is the ability to change the nameservers set at your domain registrar.  That is what routes your site’s DNS and proxied traffic through Cloudflare instead of sending requests directly to the server.

If your hosting already includes Cloudflare integration, setup can be faster because you can connect it from the hosting dashboard rather than doing every step manually. 

Cloudflare FAQs

Cloudflare next steps

Cloudflare can improve content delivery, add security controls, strengthen DNS performance, and reduce the load that reaches your origin server. It works best when the hosting underneath it is solid and the caching rules fit the way your site actually behaves.

A good next step is to decide whether your main need is speed, security, DNS management, or traffic handling. That makes it easier to decide whether the free plan is enough or whether you need more advanced controls.

If you want Cloudflare in front of hosting built for performance and stability, start by comparing Liquid Web’s managed WordPress hosting, VPS hosting, CDN hosting, and dedicated servers. That gives you a stronger origin under the edge layer and a clearer path as your site grows.