What Problems to Identify Before Choosing a CDN
January 7, 2016 | Robert GibbThis is the first post in a series that covers all 6 steps of the CDN Framework - a guide designed to help you acquire and maintain the best CDN solution possible. Before choosing a CDN, or an alternative to your existing CDN, it helps to identify problems with your website or current CDN. Investing time in this type of review will help you choose the absolute best CDN for your evolving needs. In this post we’ll direct common problems that businesses with and without a CDN solution face. We’ll then help you determine if a new CDN can help you resolve these problems. After reading this post and performing any necessary tests and research, check out step 2.
Common Problems for Users Without a CDNBusinesses with an owned online presence typically start investigating CDNs after identifying one of two problems: slowness or downtime. Because these problems lead to brand degradation and revenue loss, the need for a CDN solution becomes urgent. Growing businesses are especially vulnerable to the impact of these problems: Consider a business that makes a bold appearance on a widely televised news channel. A compelling link with a special offer is put at the bottom of the screen. Viewers flock to the website in an unanticipated volume. The first thousand viewers that hit the website experience slow loading times. The remaining viewers experience nothing at all (downtime). After such an event, many businesses would feel pressured to choose a CDN the next day or the day after. But this would be the wrong approach. By making a decision out of urgency and fear, the business could get wrapped up in an expensive contract, or worse, an annual contract with a fledgling CDN. To avoid replacing one problem with another, identify the causes of performance-related problems.
Slow Loading TimeIf your users are experiencing slow page load times, implementing a CDN could only be a “band-aid” fix rather than a complete web performance fix. To figure out why your pages are loading slow, start by running a test with ALL of the following performance testing tools:
Server DowntimeIf you’ve experienced downtime, or simply want to prevent downtime, implementing a CDN is almost always a good move if you have a lot of static content. Static content, compared to dynamic content, is content that doesn’t change based on user. Every user experiences static content the same. Examples of static content include images, audio files, video files, text files, and .html pages.
Related Blog Post: The Difference Between Dynamic and Static Web Pages
- The first test should include both dynamic and static content. Gradually ramp up the simulated user load over the course of an hour or so until you hit your site’s breaking point. You’ll know when you hit the breaking point because your site’s response times will become unacceptably slow or will start having errors (503 or socket timeouts are among the most common). Keep track of the test results and the number of concurrent users at which your site broke down.
- Run a second load test that’s identical to the first test in every way, except that it EXCLUDES static content (images, stylesheets, etc.) that could be offloaded to a CDN. Ramp up the user load gradually at the same rate as in your first test. Take note of the site’s breaking point in this second test as well.
Common Problems for Users With a CDNProblems can arise with your current CDN provider in weeks, months, or years after signing your initial contract. Problems experienced within weeks or months are often due to the provider under-delivering on its promise. This “promise” includes statements made on the provider’s website (best support, fastest response times, etc.) and in the contract (service level agreement). Problems experienced years after are often related to price and lack of features. For instance, a provider that satisfied your needs at the start may not be generating the features you now need to scale. In addition, the provider could now be charging you more for a platform that’s stayed relatively the same over the years. Here are the most common problems that cause a business to start researching other CDN providers:
- Unfavorable pricing
- Poor performance
- Poor support
- Lack of features
Unfavorable PricingThere are three issues related to CDN pricing: lack of transparency, bandwidth costs, and feature costs. Transparency According to Dan Rayburn, EVP of Streaming Media, there's a lack of transparency in regards to CDN pricing. “In my experience,” he says, “it’s not uncommon for a customer to receive a statement from their provider that says X amount is owed this month without any specific breakdown of services used.” As a CDN customer, you should know what every charge on your bill means - and you should expect it. If you’ve been charged ambiguous fees, and, furthermore, have a hard time getting in touch with billing to understand the charges, there’s a problem. Bandwidth Costs According to Steve Lerner, Senior Member of Technical Staff at eBay, Inc: “Bandwidth pricing has come down to be close to transit pricing, so CDN decisions aren’t based so much on bandwidth economics but on efficiency and performance.” This is true, but as a CDN provider ourselves, we know that bandwidth pricing is still a pain point. Fortunately, CDN bandwidth is starting to become commoditized, making it easier to negotiate pricing. Because of this, you should speak to your CDN provider before choosing another CDN, especially if bandwidth cost is the only problem. It’s always unfortunate and inconvenient to have to leave a provider you like because of bandwidth pricing. Feature Costs Additional features that support new best practices for the open web should be supported at minimal cost. Take SSL for instance. As we found in some brief research, securing CDN content can be as little as $99 and as high as $1500. For something that is becoming a web standard - and is already a ranking signal for Google - a feature like this should not cost an exorbitant amount. (The provider should even offer a free shared SSL option for smaller companies.) If you believe your provider is overcharging for SSL and other common features, a switch may be in store.
Poor PerformancePoor performance is any network-related issue that negatively impacts your website and bottom line. It’s often related to downtime or high latency. Downtime While it’s uncommon for a CDN to experience a complete outage, it does happen. What’s more common is for a single edge location to experience downtime. In either case, if your CDN has experienced consistent downtime that has caused you and your users frustration, you may want to start researching other providers. Some ways to find out if your CDN is experiencing downtime is to 1) draw correlations between user complaints and your CDN’s status pages (here’s our status page), and 2) schedule regular synthetic monitoring tests for CDN objects.
Related Blog Post: How to Test and Benchmark CDNs
Related Blog Post: DNS Load Balancing - Comparison of 4 Services
Poor SupportSome CDNs are faceless. They give you a network, but no personnel to help you effectively leverage that network. According to Dan Rayburn, it’s the CDN’s duty to do the following:
- Hold your hand through initial setup
- Show you how to interact with the control panel
- Offer transparency through status reports
- Provide near-instant support in your preferred format (phone, web chat, written tutorials)
Lack of FeaturesDifferent people have different ideas of what features are needed to make a CDN great. But these don’t matter as much as the CDN features you need to deliver a great content experience. Definitely leverage expert recommendations, but don’t abide to a single recommended feature set when making your decision. For instance, these features are considered important by Ilya Grigork, a web performance engineer at Google who's adamant about making secure connections fast: If you're delivering HTTPS-enabled pages, many of these features could be very important to you. But if your bottom line doesn't rely on delivering secure pages, these features may not be as important.
Related Blog Post: The SSL Performance Myth, and Tips for Making Secure Connections Fast