Google Demands Speed—Do You Need A Content Delivery Network?

With Google upping the ante on speed of delivery as a factor in relevance ranking, even medium to smaller sites may now need to consider a content delivery network to supplement the performance of their primary servers.

A content delivery network (CDN) is a network of computers used to increase the speed of delivery of a website to users, as well as decrease the load on the originating web server. A CDN has delivery servers placed at data centers all over world. Each of these servers is fed data from one originating web server, the content of which is then transferred to every server in the network. When a user accesses a website, they are viewing a copy of the website served from one of these networked computers.

The primary benefit of using a CDN is reducing load on the originating server. Each user is served data from a computer the CDN sees as the closest to their computer. This decreases the bandwidth used by your servers. The second benefit is that this proximity greatly reduces the time it takes to serve the content, thus speeding up the website in the eyes of the user. Speed is good right? Decreasing the time it takes to load a website is great, especially when the “user” is Googlebot, and delivery includes traversing and indexing of your content. An additional benefit, if you are using one of the newer up-and-coming CDNs, is cost. The setup and management is simple (no real code changes to your site) and the prices start at just a few hundred dollars a month. This is relatively inexpensive for what you get in return.

While the benefits seem like a no-brainer, it’s important to keep in mind that using CDNs, like any other technology, requires a certain level of trust. You trust the network to deliver your content from the closest computer, or the most available, or the least expensive location depending on how you want to be optimized. But does having many copies of your site on many computers all over the network lead to duplicate content issues?

We’ve been asked this question a lot. The ultimate answer is no—and here’s why. External search bots, such as Googlebot, key off a domain name, not an IP address. Each computer on the network has a separate IP address, but all point to the same domain name. Because of this, the content on each of the edge computers is essentially one as far as search engines are concerned. No need to worry about being penalized for duplicate content.

Improving And Optimizing Search With CDNs

A user or search bot can’t access a site that isn’t live. Uptime, in the case of server errors, power outages or even major hardware failure is one of the areas of optimization that can be enhanced with a CDN. More uptime equals more trust. If your site goes down for some unknown reason, a CDN can kick in automatically based on certain response messages (500 server errors for example) and cache your site for a preset time. This will limit your site to static delivery for this time period, but that’s worth it when the alternative is your site being down for an indeterminate amount of time.

And don’t underestimate the benefit of speed from having a CDN deliver your content and assets. Does your site have video, flash or large images? Most of the time it takes a website to load is spent getting this content to your browser. This slowness can affect not only your site’s users, but also its perceived speed by search engine robots. When Google changed the way it loads data into its index with its recent Caffeine update, speed was added as more of an influence in ranking. Google uses speed as one of over 200 factors when ranking websites. The algorithm still mostly relies on relevance, reputation and so on, but speed has become a larger part of the mix. In fact, Google has a page devoted to showing you how to help make your site faster. Using a CDN will improve site speed through cache, compression of digital assets and serving your site from the network (making a shorter trip to your computer).

Since we’ve added a CDN in front of our network, we’ve seen significant increases in number of pages indexed and number of pages in the top ten on search engine results pages (SERPs). Adding a CDN to your site is worth the investment, an investment that is decreasing as newer companies are making the industry more competitive and driving prices down. Shop around and you’ll not only make your users happy, but you’ll also see how the benefits of CDNs strengthen your SEO program.