GlossaryNetworkingBeginner

CDN (Content Delivery Network)

A CDN is a network of servers spread across the globe that stores copies of website content close to users for faster loading. It also protects sites by absorbing traffic spikes and filtering malicious requests.

Last updated June 8, 2026

Definition

A Content Delivery Network (CDN) is a geographically distributed group of servers that cache and deliver website content - images, scripts, videos, and pages - from a location near each visitor. Instead of every request traveling to a single origin server, the nearest CDN edge server responds, cutting latency and load times dramatically.

How it works

When a user requests a page, DNS routes them to the closest edge node. If the content is cached there, it is served instantly; otherwise the CDN fetches it from the origin, stores a copy, and serves future requests locally.

Why it matters for scraping

  • Anti-bot gateways - providers like Cloudflare and Akamai sit in front of sites as CDNs, inspecting and challenging suspicious traffic.
  • Geo-variation - CDNs serve different content by region, so the IP and location of your proxy affects what you scrape.
  • Rate limiting often happens at the CDN edge, requiring IP rotation to scale.

Understanding CDNs is essential because most large sites are fronted by one, meaning your scraper interacts with the edge - and its bot defenses - long before reaching the real server.

Examples

1

Cloudflare caching and protecting a website while challenging suspicious bots

2

Akamai serving streaming video from edge servers near each viewer

3

Amazon CloudFront delivering static assets for an e-commerce store

Common Use Cases

Recognizing when a target site is fronted by a CDN with built-in anti-bot defenses
Using geo-targeted proxies to capture region-specific content served by a CDN
Rotating IPs to avoid edge-level rate limiting during large scrapes
Diagnosing why scraped content differs from what you see in your own browser

Frequently Asked Questions

A CDN caches copies of website content on servers around the world and serves each visitor from the nearest one, reducing load times and offloading traffic from the origin server.
Many CDNs double as anti-bot gateways that inspect, challenge, or block automated traffic, and they also serve region-specific content, so your proxy choice directly affects scraping success.
Yes. Cloudflare is a CDN that also provides security and anti-bot features, so scrapers frequently encounter its challenges before reaching the underlying website.

Keep Learning

All terms

Web Scraping

Web scraping is the automated extraction of data from websites — fetching pages programmatically and parsing their content into structured data.

Read definition

DNS (Domain Name System)

DNS is the internet's phonebook — it translates human-readable domain names like example.com into the numeric IP addresses computers use to connect.

Read definition

Geo-Targeting

Geo-targeting is selecting proxy IPs from a specific country, region or city so your requests appear to originate from that exact location.

Read definition

Rate Limiting

Rate limiting restricts how many requests a client can make in a given time, and it is one of the most common defenses scrapers must work around.

Read definition
Back to Glossary