A Content delivery network (CDN) is a globally distributed system of servers that delivers website content. Servers are located geographically close to users to deliver content fast. The nature of close proximity servers decreases slow load times associated with geographic distances.
Simply put, a CDN is a globally distributed caching system. This does not provide too much clarity, so let’s take a look at an example.
Example of a Content Delivery Network
Let’s say a user in Germany is trying to access a PDF document with the origin lacation in California. The PDF has to travel from California all the way to Germany for the user to view. This situation creates a slow page load time for viewing the document.
What the CDN does is downloads this PDF to a local server in Germany for more rapid viewing the second time. The long load time associated with the document traveling electronically from California to Germany will occur once. For the initial user. The second time a user requests this document in Germany, the document will come from the local server in Germany. The result is a faster download.
This situation occurs for users anywhere in the world. CDN servers download documents locally.
Content Delivery Network Advantages
CDN servers are helpful for many reasons. This includes:
- Better bandwidth management
- Lower latency of static content
- Globally distributed servers
- Enhanced user experience
A CDN works best with static content, as the CDN server updates each time there is a new document. A CDN is a globally distributed caching system.
Content Delivery Network Disadvantages
The largest advantages of a CDN are in the distribution of static content. Here are some disadvantages:
- High cost
- Security
- No-caching of dynamic content
- Impractical for smaller companies
- Maintenance
One of the biggest struggles of a CDN is its caching of dynamic content. Most CDNs classify dynamic content as non-cacheable. In turn, this creates the slow load time we discussed in the example above. As more content becomes dynamic, which can be seen in the marketing world, this will create specialization in content delivery.
After considering the above, we have a new question. What are the big players in content doing to solve their content delivery dilemmas?
The solution is, Google and Twitter are moving to work together. They teamed up to deliver a dynamic content solution. The solution is to provide cached versions of articles that appear in search results. It means Google will host more content. This solution effects publishers the most. The main purpose is for the use of delivering more content to mobile users. What this means is, we have identified there is an issue with delivering dynamic content.
Content delivery is a big issue, whether for static or dynamic content. There is no one size fits all approach. We hope this helps provide insight into what role a CDN will play in your content delivery solutions.
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