A CDN will drastically reduce server lag by storing static resources on a network of fast loading servers.
Choosing a CDN can be tricky since there are many options available. Finding the right one depends entirely on your needs and the popularity of your site.
In this post we’ll look at some of the more popular CDNs available for websites, big and small. I’ve deliberately excluded some CDN companies, such as Akamai and Level 3, which are better suited to large-scale enterprise sites.
What is a CDN and Why Use One?
The CDN provider copies your site’s static content to its servers, so when someone lands on your site, the static content is delivered from the server closest to them.
For a visual look at how this works, check out this handy graphic from GTmetrix:
Free Trial: If you use over 15TB a month you qualify for a free MaxCDN trial. This includes everything that comes with a MaxCDN enterprise account, including unlimited bandwidth, negotiable trial length, all features enabled, and one-on-one setup call.
Pricing: Basic Start Plan comes with 100BG bandwidth for two websites for $9 a month.
MaxCDN is a popular and well-known CDN that powers the likes of The Next Web, The Washington Times and WP Engine.
An elegant control panel displays a CDN usage summary for your website, and you can also access information such as hourly breakdown, edge locations users, and your top 50 files.
The service has servers all over the world, including the US, UK, China and Australia, with more edge locations planned. In addition, MaxCDN has 53 peering partners in North America and Europe to minimize hopes between ISPs.
Free Trial: CloudFlare offers a basic free plan that includes fast site performance, board security protection and powerful stats about your visitors.
Pricing: Plans start at $20 per month for your first website and $5 per month for each subsequent website.
CloudFlare is another well-known CDN service. Unlike many CDNs, CloudFlare doesn’t charge for bandwidth usage on the basis that if your site suddenly gets popular or suffers an attack, you shouldn’t have to dread your bandwidth bill.
According to CloudFlare, on average a website using the CDN will load twice as fast, use 60 per cent less bandwidth, have 65 per cent fewer requests, and is more secure.
CloudFlare operates out of 28 data centers around the world and uses a technology called Anycast to route your visitors to the nearest data center.
Free Trial: No.
Pricing: Plans are pay-as-you-go and start at 10 cents for your first terabyte of storage and 12 cents for your first terabyte of CDN bandwidth.
Rackspace Cloud Files offers online object storage for files and media and uses Akamai, a third-party CDN, to deliver your files globally.
The service uses more than 200 global edge locations around the world so your users get content fact and from servers within their region. Cloud Files maintains three copies of each files, ensuring files are delivers fast and reliably.
Rackspace’s partnership with Akamai is significant. The CDN is one of the world’s largest distributed computing platforms, responsive for serving between 15 and 30 per cent of all web traffic. Some of the company’s customers have include Facebook and Twitter.
Free Trial: 30-day free trial.
Pricing: Plans start at $99 a month for 256GB bandwidth transfer and 1000MB storage.
CacheFly promises to deliver your static files (images, video, audio, CSS etc) at up to 10 times faster than other solutions. The company even guarantees 100 per cent network availability or your money back.
Microsoft, Adobe and Bank of America are just some of CacheFly’s clients.
While CacheFly has a solid reputation – and has clients who have stuck around since they started in 2002 – the only downside is that it’s one of the most expensive CDN options.
Free Trial: No.
Pricing: A Small plan starts at $30 a month and includes two WordPress site, 10GB SSD storage and 100GB bandwidth.
WPPronto makes it onto this list because it started out as a CDN (the company launched in 2009 at WPCDN) and has since pivoted to focus on web hosting.
The company offers a CDN service using CloudFlare. It also focuses on security, offering multiple layers of protection (including DDoS attached production), SSL for everyone, and support Clef two-factor authentication.
Free Trial: No.
Pricing: Plans are pay-as-you-go at a set price of 12 cents per gigabyte of CDN bandwidth or 15 cents per gigabyte of CDN SSL bandwidth.
SoftLayer, an IBM company, offers cloud infrastructure as a service from data centers and network points around the world. Its customers range from startups to global enterprises.
The company uses the EdgeCast CDN to provide 24 content delivery nodes around the world, in additions to SoftLayer’s 13 data centers and 17 extra network points of presence.
Free Trial: The AWS Free Usage Tier includes 5GB of Amazon S3 storage, 20,000 get requests, 2000 put requests, and 15BG of data transfer out each month for up to 12 months.
Pricing: Amazon S3 storage starts at 3 cents per gigabyte for standard storage. Amazon CloudFront pricing starts at 12 cents per month for the first 10 terabytes, with separate pricing for regions outside the US.
Amazon offers a couple of services I’ll mention here. Amazon S3 is a budget-friendly storage solution designed to make web-scale computing easier for developers. Amazon CloudFront is a CDN that gives any developer access to the same highly scalable, reliable, secure and fast infrastructure that Amazon uses to run its own global network of websites.
While Amazon AWS has a reputation for reliability, it’s good to keep in mind that CloudFront is aimed at developers and not inexperienced users.
Free Trial: 14-day trial.
Pricing: Pay-as-you-go plans started at $49 per terabyte up to 30 terabytes for US and European customers. Prices are much more expensive for users in other regions.
CDN77 sets itself apart from other CDNs with specialized software, video and gaming delivery for uninterrupted streaming.
It’s a relatively young CDN, having started only three years ago, but it’s quickly built up a stable of 25 data centers in 21 countries.
Free Trial: A free plan includes bot protection, access control, login protect, CDN and Optimizer, website analytics, and community support.
Pricing: A basic Personal plan starts at $19 per month and includes the same features as the free plan, plus SSL support, advanced performance and email support.
Incapsula offers global CDN and caching (dynamic and static), including content that other CDNs might consider uncacheable.
On average, websites using Incapsula’s CDN are 50% faster and consume 40%-70% less bandwidth, according to the company’s website.
The service provides a great monitoring dashboard so you can check the effect of caching on your website’s performance.
There’s also an API for companies that want to control caching policies and change things like caching modes, create custom caching rules, purge the cache, purge a specific cache, or configure content optimization settings.
Free Trial: Free product.
Pricing: Free product.
Photon isn’t a CDN, but it makes this list because it provides a WordPress-only image caching service through the Jetpack plugin. This means less load on your hosting server and faster images for your visitors.
There are a few limitations with this service. There are no cache invalidations, so currently the images are cached “forever” and if you want to refresh an image you will need to change the name of the image. Also, Photon only caches GIF, PNG and JPG files.
Free Trial: Free service.
Pricing: Free service.
The service is supported by CloudFlare and MaxCDN.
Choosing a CDN
Knowing your website’s specific needs is key to choosing a CDN.
Before signing up for a CDN, it’s important to have a clear outline of what your are looking for.
What are your bandwidth needs? Are you going to use 10GB per month or 10TB per month?
To find your bandwidth usage, login to your web host to access your bandwidth stats.
If your site gets little traffic, it might not be worth signing up for a premium CDN. A free service, such as Photon by Jetpack or Cloudflare’s free service will suffice. Alternatively, you may want to consider upgrading your hosting.
When you are delivering about 500GB per month of traffic it makes sense to offload those hits to a CDN.
If you provide videos, podcasts, music, large images, and software downloads, a CDN will ensure your visitors are able to access your media quickly.
Where are your users located? How many servers do you expect a CDN to have, and where?
If the majority of visitors to your site are based in the US, it makes sense to go with a CDN with servers spread across that region. However, if you have a spread of visitors from across the US, Europe and Asia, it would be better for your content to be available on servers in those regions.
It’s also important to note whether a CDN offers a push or pull service. A push CDN works very much like a secondary server. The user uploads content directly to the CDN (automatically or manually) and links to it. With a pull CDN, the site owner leaves the content on their server and and rewrites their URLs to point to the CDN. When asked for a specific file, the CDN will first go to the the original server, pull the file and serve it. The CDN then caches that file until it expires.
Do you require streaming downloads, such as video, audio or software downloads? Do you run a gaming website?
Some CDNs, like CDN77, offer speciality services that support streaming.
Also, check whether a CDN offers quality analytics and real-time monitoring features.
What kind of support do you expect from a CDN?
It’s easy to check what kind of support is on hand, whether it be live chat or email support. Some CDNs offer technical assistance over the phone.
It’s also worth noting whether a CDN is available 24/7, and having a look through their service level agreement.
Most CDNs offer a 100 per cent SLA, but you don’t want to have to chase down credits if your CDN doesn’t meet it SLA.
How much are you willing to spend? Will you be compensated for network outages?
There are huge differences in cost from one CDN to the next, and plans differ from pay-as-you-go to monthly accounts with set features.
The price you pay will depend on the CDN plan that best meets your needs and how much traffic lands on your site.
Many CDNs offer free trial periods so if you’re interested in trying out a CDN you’ve got nothing to lose.
Best CDN for Multisite?
The jury’s still out on this.
While many services support WordPress, the lines blur when it comes to Multisite.
Services like MaxCDN, CloudFlare and Rackspace can be integrated with WordPress using W3 Total Cache, but the caching plugin still doesn’t fully support Multisite (you can use it on sub-sites and the main site, but not an entire network).
If you’ve used a CDN successfully with your Multisite network, I’d be interested to read about your experience in the comments below.
Where once websites were delivered from a single server, CDNs have revolutionized how online content is delivered, ensuring sites load quicker and downloads are faster and more reliable.
If you run a small to medium-sized site (around 40,000 to 50,000 page views), MaxCDN, CloudFlare and Rackspace are both solid options for your needs.
Services such as Amazon CloudFront are better suited to enterprise level sites and are overkill for sites with minimal traffic.
For small sites, Photon and jsDelivr, along with CloudFlare, are great options since each of these services are free.
Sites offering streaming media, such as video, audio and gaming, should check out CDN77 and it’s tailored service for this kind of media.
Do you use a CDN? Tell us about your CDN experiences in the comments below.