CDN : Content Distribution Network. The Need For Speed. Is It Right For You?
Everybody wants it…speed, quick, fast, instant now. Wait more than 2 seconds and any marketer will tell you, your bounce rate will go up and you will lose business. Your site will be graded into a A, B, C, D or even F category. Your ranking diminished. If you are curious how your site would do, some good ways to check are GTmerix, Google Developer’s Insight, or Pingdom.
The challenge is, the internet was not made for such lighting speeds. At least not for the common man and yet that is the very thing that business are asking for, in fact demanding. But at the very same time, they don’t want to pay for the hosting that has a shot of delievering such a request. So what do you do?
Enter the Content Delivery Networks.
What is a CDN?
A content delivery network (CDN) is a group of geographically distributed servers that speed up the delivery of web content by bringing it closer to where users are. Data centers across the globe use caching, a process that temporarily stores copies of files, so that you can access internet content from a web-enabled device or browser more quickly through a server near you. CDNs cache content like web pages, images, and video in proxy servers near to your physical location. This allows you to do things like watch a movie, download software, check your bank balance, post on social media, or make purchases, without having to wait for content to load.
You could think of a CDN like an ATM. Having a cash machine on practically every corner makes it fast and efficient to get money. There’s no wait time in long bank lines, and the ATMs are placed in many convenient locations for immediate access.
CDN services were created to solve the problem of network congestion caused by delivering rich web content, such as graphics and video over the internet — much like a traffic jam. Getting content from centrally located servers to individual users simply took too long. CDNs have now grown to include everything from text, graphics, scripts, and media files to software downloads, documents, portals, ecommerce, live streaming media, on-demand video streaming media, and social media sites.
CDNs can also provide websites with increased protection against malicious actors and security concerns like distributed denial-of-service (DDoS) attacks.
How does a CDN work?
The goal of a CDN is to reduce the amount of time it takes to load a webpage, aka, ‘Latency’. Latency is that annoying delay you experience when trying to access a web page or video stream before it becomes usable on your device. Although measured in milliseconds to seconds, it can feel like forever to a users, and may even result in the potential viewer bailing out in frustration.
Some content delivery networks alleviate latency by reducing the physical distance that the content needs to travel to reach you. Therefore, larger, more widely distributed CDNs are able to deliver web content more quickly and reliably by putting the content as close to the end user as possible. The interesting thing is this…CDN’s are NOT hosts. So how can they do that?
They achieve this goal by having a copy of the media files in memory, aka ‘Cache’. If the content you requested is unavailable or outdated, the CDN service will store the newly fetched content to serve any future requests.
PROS & CONS
1. Quick Delivery of Assets
CDN allows for widespread distribution of servers, which is placed closer to the users makes the distribution of data quickly. This helps to load the website faster.
2. Caters to a Large Number of Users
If you own a website with a large audience base, then CDNs can be of great help to you. CDN enables a high traffic flow which can allow a large number of users to access your website at the same time without putting any extra pressure on the servers.
3. Managing Traffic Load
CDN is extremely effective at managing dynamic traffic loads. CDN with its large chain of servers ensures that the resources are scaled up and down according to the incoming traffic. Not being able to handle a sudden spike in traffic for a smaller website is a common issue.
4. Control Over Delivery of Assets
With CDNs, you’ve complete control over the deliverance of assets via different servers depending upon which servers are overloaded or under-utilized at that point in time.
5. Expands your market internationally by the use of local servers
This is the total point of a CDN. That your site can be just as fast in Italy as it can be in Japan.
6. Your SEO rankings may get better
Google likes speed. It’s network will evaluate your page, including load speeds in order to determine your overall organic search ranking.
7. Protection against attacks is easier
The hackers who want to steal your email address, covertly change your code are in full force. Having a CDN, allows you to put some distance between your real site and the invaders.
8. Supports high media sites who need help delivering
Extremely useful for websites with larger Images and videos but struggling with loading speeds
- Servers are not always up to date
In order for a CDN to work, it has to have the latest media to deliver to your viewers. Thus if you have to change your site a lot, daily or even hourly, a CDN may not keep up. It can be as long as 24-48 hours to stabilize and update the content per change. This is especially true, if you are using a free service like Cloudflare. You will need to balance the need for speed, against the need for quick updates.
- Location of Servers.
If there is a mismatch between the location of your servers and that of your audience, then the CDN won’t be of much help.
- Support can be an Issue
Since CDNs are mostly operated over third-party infrastructures, resolving an issue can involve too much to-and-fro of communication.
Some organizations and countries have blocked the domains or IP addresses of popular CDNs. In this case, your audience from these organizations or countries cannot access your website, and you will end up losing some of your traffic.
- CDN are not perfect
If the closet server is overloaded by demand, you might be faster loading from your own host. This is a variable that changes from day to day, if not minute by minute. If they go down, you are going to have to change quickly.
- Dedicated Servers may have problems
If you own or lease a dedicated server that is hosting your site, using a basic CDN is going to have issues. The redirection of the site’s IP address, will make is so your server become invisible to the net. Your only solution would be to change your hosting to a service that also offers CDN.
- There is no country or IP shield..
You may not want to do business in a particular country that has caused you problems in the past. With a CDN, there is no country or IP shield.
- Sensitive Files may be at risk
Websites are built using technologies that generate a web page and thus can be viewed by anyone, including hackers. This includes custom plugins or fully customized sites. While the firewall exists on your server, it is difficult to monitor, given you site no longer is dedicated to one static IP. All data will be copied to all distributed servers.
- Email may have issues with self-hosted service.
Self hosted email on your server does not port well on a CDN. Frequently it is seen as a hacker or spam as the email does not have just one IP address, it can come from many.
TO USE OR NOT?
The question of whether you should use a CDN, depends on the needs of your company. If you have a popular website, powerful server with enough resources, AND that does not change it’s content too often, it might pay off. It also depends on balancing the need of your audience (are they young, impatient and will bail) , google SEO demands, bounce rates, do you share a server with other sites and a group of other factors.
As a general guide, the question to ask are this:
- What is the present load speed of your website?
- How often do change the content of the site?
- Do you have a dedicated server for your site?
- Do you have information or plugins on you site, that you do not want distributed?
- Who is your audience and how demanding are they to speed?
- How is your present overall speed in relation to google ranking?
- Do you self host your email?
I am sure there are even more questions that need to be reviewed. All these items must be balanced, in order to make the right decision for your business. The technology exists, as long as it works for you and not against.
To start your review, some good place to evaluate what your present site performance is:
OUR EXPERIENCES WITH CDN
Our experiences with CDN have been mixed.
While the site speed load, from the point of view of the user, does come up incredibly fast, frequently under 1 second, the down side of email functionality and purchase race conditions, outweigh the 1 second faster load speed. We have had issues with our clients with emails failing to be delivered or the mx server not being found. There have also had race conditions with our e-commerce clients. Where a product was purchased and yet since the cache did not update across the network fast enough, another customer purchased the same product, when there was only 1 item available.
Thus, as a practical application, we do not recommend a CDN unless the following conditions are true.
1. Extreme high volume of users on the order of over 10,000 a month
2. Email is not self-hosted. Use a 3rd party service like G Suite
3. Have a paid for CDN service, with sufficient rule sets to allow for conflicts.
4. Don’t use a CDN for a poorly optimized website.
Ultimately, CDN are a tool for performance. Whether it works for you, is dependent on your business, workflow needs and how much money you want to spend. It should not be used as a cover for a slow loading site.
A CDN, should not be used as a cover for a slow loading site.
If your site is taking longer than 2 seconds to load, then you have website implementation and optimization issues to attend to. We outline some of these issues in our blog “2021 Update: Website Load Speed Report.” There you can get pointers on how to decrease load speed overall.
CEO & Technical Director of Multimedia Designs, LLC, System Designer, Developer, Producer with 15+ years in the internet design and development space and 25+ years in the Software Development for the entertainment industry. Winner of the prestigious International Themed Entertainment Association award for interactive design. She holds a degree in Computer Engineering & Mathematics from California State University, Long Beach.