Quick cache: how CDNs are getting smart to improve website performance
Content Delivery Networks, or CDNs, are impressive tools. However, like many other impressive tools, not all their capabilities have been fully enjoyed by the people who have invested in them. Just as there are people out there using Apple watches to actually tell time instead of getting lunch delivered, controlling a home thermostat or ordering an Uber, there are website owners using CDNs without capitalizing on their full caching potential due to the steepness of the learning curve.
Thankfully for all the non-tech obsessed website owners out there, the current crop of premium CDNs are getting smarter so site owners don’t have to work harder.
Cache-ing in with CDNs
CDNs exist to improve website performance, mainly through faster page load times. A CDN can do so because it is a network of proxy cache servers located around the world. When a CDN is in use, a website’s users are automatically redirected to the server closest to them, which is ready to serve up a website’s cacheable content upon request. Generally speaking, the further requests or requested content has to travel, the longer it will take, so a CDN’s setup not only eliminates trips to the origin server to fetch content, but reduces the distance cached content has to travel from the proxy cache server.
With quality CDNs, cacheable content will include both static and dynamic content. Static content is content that isn’t expected to change over time, nor is it expected to change depending on who the user is, while dynamic content is content that is generated on the fly depending on who is accessing the website, when the website is being accessed and other variable factors. Since static content remains unchanged, it’s easily stored on a cache server. Superior CDNs can also store dynamic content for the period in which it is expected to remain unchanged.
If you’re thinking this whole cached content business is sounding a little complicated, well – that was precisely the problem.
When hands-on ends up being hands-off
A CDN’s cache control traditionally has not been a plug and play feature. Optimizing cache control required that content files be manually tagged with cache headers that provide a CDN with the information necessary for successful caching. This included when individual content files expire and need to be re-fetched from the origin server, information on compressed and uncompressed content, public or private content, and no-cache or no-store content.
For many website owners who didn’t have the luxury of an IT staff or web developers who tagged content files correctly in the first place, this tagging task fell somewhere beyond their abilities, nullifying some of a CDN’s biggest benefits.
Leaving the learning to CDNs
In order to bring the massive benefits of a CDN to as many customers as possible, leading CDNs are now employing a learning-based approach in order to automatically cache a wider range of content and optimize storage and delivery. According to CDN provider Incapsula, the benefits of this intelligent type of cache control include:
A dynamic improvement
One of the biggest improvements intelligent cache control offers is its ability to identify caching opportunities for dynamically generated objects, which are pieces of content that though they may not be expected to change the way most dynamic content does, they’re generated anew with each visit and considered dynamic due to a technicality.
The new, smarter breed of CDNs are able to observe the usage patterns when it comes to these objects, and when a CDN notices the same HTML version of a piece of content is being served over and over again, the CDN is able to override the dynamic classification in order to label it as static and serve it up as cached static content. Intelligent cache control also monitors these objects for modifications, labeling it as dynamic when modifications are made so the freshest versions of these objects are always what are being served to users.
Anyone who owns or runs a website knows there’s no end to what they have to stay up to date with or become fully informed on in order to have an optimally functioning website. Thanks to the newest versions of leading CDNs that feature intelligent cache control, however, site owners are welcome to strike caching optimization off of that list. Maybe all that time that would’ve been spent on cache headers could be put towards learning everything an Apple watch can do. While the Time Travel feature isn’t as cool as it sounds, it’s still wildly useful.