A content delivery network or content distribution network (CDN) is a system of computers containing copies of data placed at various nodes of a network.

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38
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7k views

Why do big sites host their images/css on external domains?

Why do big sites (Facebook, Twitter, Google, Tumblr & so on) host their images/css on external domains? Facebook: http://static.ak.fbcdn.net/ Twitter: http://a0.twimg.com Google: ...
38
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4answers
892 views

When did you decide to use a CDN? How did you measure the “success” of using a CDN?

When did you decide to use a Content Delivery Network? How did you measure the "success" of using a CDN to help justify the additional cost? Added a bounty. Hoping to get interesting stories from ...
18
votes
4answers
22k views

Is the Bootstrap CSS on a CDN yet?

Just checking to see if anyone knows of a CDN for the bootstrap css framework.
18
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2answers
1k views

Where can I find the full list of Google/Microsoft CDN hosted AJAX files?

While Google hosts this list and Microsoft hosts this one there are several files missing such as jQuery UI CSS. Where can I find a complete listing of all the resources offered for major AJAX CDNs, ...
16
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4answers
6k views

CDN - Content Delivery Networks. How do they work and why would I want to use one?

What exactly is a Content Delivery Network (CDN), how does it work, and why would I want to use one for my web site? Which are the well-known CDNs out there?
14
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2answers
12k views

Is there a way of using HTTPS with Amazon's CloudFront CDN and CNAMEs?

We use Amazon's CloudFront CDN with custom CNAMEs hanging under the main domain (static1.example.com). Although we can break this uniform appearance and use the original ...
12
votes
5answers
3k views

What is the advantage to hosting static resources on a separate domain?

I notice a lot of sites host their resources on a separate domain from the main site, e.g. StackExchange using sstatic.net, Barnes & Noble using imagesbn.com, etc. I understand that there are ...
12
votes
2answers
458 views

When to switch to a CDN?

I have read about CDNs and what they do. The question I have is three fold. When should you start to use a CDN? My site is small currently and do not see the need for a CDN but is there a general ...
12
votes
4answers
5k views

How to use Cloudflare and Namecheap email forwarding at the same time?

I want to use Cloudflare, and it requires that I use their nameservers. The problem is that I'm using some features from Namecheap like email forwarding, which will be disabled (if I didn't get it ...
11
votes
3answers
26k views

What's the best FREE CDN service available? [closed]

It seems like using CDN is a best option to provide users a great browsing experience. But, plans of the major CDN providers seem costly. So, I would like to get used to the CDN thing before I ...
11
votes
1answer
468 views

When and when not to use a CDN

I'm working on a web-application that loads a couple of small gif images onto the screen. I'm using a relative path, which means they are loaded from the same web server that serves the php page. The ...
10
votes
2answers
2k views

Image CDN with API?

My company uses flickr and picasa web albums as poor man's content delivery networks (CDN) for image hosting, but I'm curious if anyone has any recommendations on any other services that might be ...
8
votes
2answers
2k views

How does a CDN like CloudFlare work?

What I understand so far: You keep your current web hosting, but you change the DNS servers for your site from the DNS servers of your current hosting to CloudFlare's DNS servers. CloudFlare serves ...
8
votes
4answers
730 views

Google doesn't crawl CDN files

I've noticed that Google Webmaster Tools is reporting a lot of blocked resources in my website. Right now all the "blocked resources" are .css, .js and images (.jpg, .png) that I serve from Cloudfront ...
8
votes
1answer
4k views

How does CloudFlare's Rocket Loader actually work (and how can a developer ensure compatibility)?

CloudFlare has quite a ground-breaking technology called Rocket Loader (both on free and paid accounts). But how does it actually work? They have a couple of pages that describe the technology, but ...
7
votes
3answers
12k views

Is it possible to use cloudflare without having them managing my DNS?

I need to use cloudflare without having them managing my DNS, My DNS server have much more options that I do need. Instead of setting cloudflare as my dns server, I have added it as a NS record from ...
7
votes
2answers
3k views

is it true that CloudFlare really doesn't affect dynamic content?

I've been reading the CloudFlare FAQ, I understand that is acts as a reverse proxy and all requests to your domain will go through CloudFlare. They say in the FAQ that it won't slow down dynamic ...
7
votes
2answers
3k views

Can I use imgur as a CDN?

I have an e-commerce site and I want to use imgur.com as a CDN for my product images by setting the image source of my image. I did not see anything in the ToS specifically about this. Can anyone ...
7
votes
1answer
566 views

How is Apple's enormously image-heavy site served so fast?

Took a profile of the "Smart Cover" page on Apple's site using Pingdom. It's requesting 241 objects for a total page weight of 3472.6 KB! An absolute mammoth. How does this possibly translate into ...
7
votes
2answers
197 views

Separating static/uploaded content from the site

I have a site where I anticipate to have a large amount of users. I've heard that it is a good idea to separate user content (uploaded images) and place them on a separate static server where lighttpd ...
7
votes
1answer
238 views

How much do other CDNs charge? [closed]

I'm currently using Amazon S3 and CloudFront as a CDN to serve my images. Amazon publish their prices on the site: $0.120 per GB transfer and $0.0075 per 10,000 HTTP Requests. However, other CDNs ...
6
votes
7answers
423 views

Looking for a CDN [duplicate]

Most of the CDN's that I've seen require you to upload your content in advance. I'm looking for a CDN that, upon receiving a request for a resource it hasn't seen, will contact my application server. ...
6
votes
3answers
513 views

Creating a CDN to boost page ranking?

I had a thought about CDNs and if they affect page rankings. Lets say hypothetically if I was to create a CDN as a subfolder in my site. This folder would contain a resource that is useful e.g. ...
6
votes
2answers
23k views

Font blocked from loading by Cross-Origin Resource Sharing policy: No 'Access-Control-Allow-Origin'

we are experiencing this error in Google Chrome. We thought everything was set-up correct. But maybe not? Font from origin http://skin.cdn.com has been blocked from loading by Cross-Origin ...
6
votes
2answers
1k views

How does a CDN work on the tech side?

I never used a CDN before so this is a noob question, but how does it work on the tech side. For example right now when a user uploads an image on my site it is uploaded to the "/uploads" folder at ...
6
votes
2answers
655 views

CDN solutions pros and cons

As the sysadmin in our organization I've been asked to look into CDN solutions as we have plans to roll out a web platform that is targeted at developing countries. Here is my research so far on the ...
6
votes
1answer
765 views

Does google contribute ranking from cdn.example.com to example.com?

Background From my understanding, http://mywebsite.com/image.jpg, can help the ranking of http://mywebsite.com in a search engine, such as Google (obviously the search engine of primary concern). ...
5
votes
1answer
4k views

HTTP Header Cache Time: s-maxage and max-age

I am setting up a CDN for my website, I found the following sample for adding to the 'httpd.conf' file, this is used to adjust the cache-time for client and CDN: ExpiresActive On ExpiresByType ...
5
votes
1answer
320 views

Is Cloudflare unzipping gzipped dynamic content?

I'm using Cloudflare for a small website that is frequently accessed from mobile phones where bandwidth usage is crucial. I used to gzip every php response and this reduced my bandwidth usage, ...
4
votes
5answers
835 views

Is it ethical to use Google Analytics on a site crime victims use to make 'anonymous' reports?

Our local police force have a website for rape victims to use to report attacks anonymously. At the top of the page is a 'Report anonymously' link, which takes you to a page using Google Analytics as ...
4
votes
2answers
171 views

Do browsers recognize the same files served by different subdomains?

I have my website assets stored on Amazon S3 and served by CloudFront, from a separate domain name, to act as a cookie-less domain (so website.com for the website and websitestatic.com for static ...
4
votes
2answers
926 views

CDN for authenticated sites

We have a site that requires users to sign into. Typical stuff. Today, all the content (dynamic and static) is behind the login process, and you cannot access any of the pages or files via a URL ...
4
votes
5answers
2k views

Does it matter where a server's physical location is?

I am located in the UK, and most of my clients are also in the UK. However. I find some of the products available in the US to be easier to use. I won’t name specific companies, but the price and ...
4
votes
2answers
374 views

Concerns about moving media files to a CDN and impact on SEO

I'd like to move all my media files to a CDN (Windows Azure is my best choice for now). Two questions : How can I avoid SEO and redirections issues for the previously uploaded media files ? For ...
4
votes
1answer
2k views

Costs of hosting static files on Google App Engine

I am considering using GAE as a kind of CDN, to host an entire static website. Soon they will start using new pricing. Does every site visitor start a frontend-instance? What will be the cost ...
4
votes
3answers
2k views

Does CloudFlare cache videos, and would this wildcard Page Rule work for that?

I'm setting everything up in my website to use CloudFlare. This is my example: On videos.domain.com/Folder-A/Folder-B/ there are some HTML files that I would NOT like CloudFlare to cache. But inside ...
4
votes
1answer
200 views

CName for static images - will Google crawl?

I am planning to serve images on a CDN using a CNAME: images.mysite.com. I am doing this because CDNname.mysite.com makes ugly URL's and MAY be bad for SEO (debatable). Will Google crawl the ...
4
votes
1answer
713 views

Google CDN or Akamai

We combine and minify our JS with Minify - the combined JS is then cached on Akamai. I'm suggesting to my supervisor that we put JQuery and JQueryUI on Google CDN and take it out of our combined JS. ...
3
votes
9answers
270 views

How do you enhance your websites speed without compromising the design and access?

How do you enhance your websites load speed without killing the design and accessibility? File compression, CDN, Gzip? What are the best tools for doing so? For example, Google has optimized their ...
3
votes
3answers
117 views

Two different websites with same product images

I need some advice from more experienced webmasters. I have 2 websites (site A and site B). These websites are totally different, but they use same product images (around 1 GB of images). These ...
3
votes
2answers
997 views

Images on a subdomain, hosted on the same server — will simultaneous downloads increase? (CDN)

Browsers only allow you to download a limited number of concurrent files from the same domain. Would a subdomain for images (basically as a content delivery network) on the same web hosting server ...
3
votes
1answer
3k views

Can Amazon Cloudfront files be served GZIP'd?

If i'm running a WordPress website with the W3TC plugin installed, and have my static CSS/JS minified files hosted on Amazon's CDN, is there a way to serve them GZIP'd? I have the basic understanding ...
3
votes
3answers
965 views

Need a CDN with SSL [closed]

We currently use Edgecast through Speedyrails. Back when I did my research they were both fast and very cost-effective. I haven't looked in a while, but now we need SSL on our assets as well. I ...
3
votes
1answer
3k views

How to make CloudFlare cache everything?

I want CloudFlare to cache everything, PHP files too, every request from the domain, I want it to cache it. Is this possible? (There are PHP scripts on the domain that print out images, JS and CSS, ...
3
votes
3answers
302 views

Is it possible to know where a CDN's servers are located?

Are there any tools or online applications that can list where a CDN's servers are located?
3
votes
3answers
76 views

About cdn architecture to route way

Our web system, use the third-party cdn service. Assume that the user set the local dns with the googledns or opendns to visit our web sites, so cdn service will select the closest cdn proxy node. ...
3
votes
1answer
299 views

Receiving error 500 for WordPress when using CloudFlare as a CDN

My WordPress site is using CloudFlare as a CDN, and if I use the site's IP address to access wordpress/wp-admin/install.php directly, it works fine. However, when I try to call ...
3
votes
1answer
788 views

Do I set a DNS A Record for the new GitHub Pages to use their CDN?

GitHub updated their Pages service for custom domains yesterday and I'm not clear on one small detail. They recommend a CNAME record for www.example.com but do not recommend using A records for the ...
3
votes
2answers
349 views

prevent hotlinking of off-site content?

I have a www.example.com site where I serve all static content (e.g. http.//www.example.com/image.jpg) off a CDN with URLs like http://static.example.com/image.jpg An Apache 2 .htaccess rule ...
3
votes
2answers
2k views

why is my site slower with amazons cdn?

so I have move most of the static objects to amazons Cloudfront CDN example: http://images.storyfollower.com/images/cycleOfStories.jpg which through cname point to the cdn Now I just ran a speed ...