Cloud Files CDN Compresses at the Edge

Distributing your files over a content distribution network (CDN) is all about increasing speed and expanding your global footprint.  The Cloud Files team is dedicated to making sure our CDN is up to date with technologies that can increase that performance whenever possible.

We are pleased to announce the launch of HTTP Compression on the Cloud Files CDN.  HTTP Compression is a simple, cost saving process.  When a browser requests an object, it may also supply an “Accept-Encoding” header that tells the CDN whether or not it will accept a compressed response. The CDN will then serve the object compressed, or not, at the browser’s preference. With this feature, the Cloud Files CDN is smart enough to know how the browser wants the object, convert that object and serve it accordingly.

Compression occurs when you store an object in Cloud Files and serve it over the CDN.  HTTP Compression will only work for uncompressed content in Cloud Files that the browser requests to be served compressed over the CDN.   If an object is stored in Cloud Files compressed and the browser requests to serve it uncompressed, the CDN edge can’t currently convert the object.  We plan to add this functionality (storing compressed files and serving them uncompressed) in upcoming releases.

Why do you want HTTP compression on your CDN?

Compressed objects can be downloaded more quickly than uncompressed objects resulting in faster page load times for your users and lower bandwidth costs for you. The Cloud Files CDN supports compression on HTML, JavaScript, and CSS, files ( “text/html*”, “application/x-javascript*”, and “text/css*” content types, respectively).

This feature has been added to Cloud Files functionality and does not require any specific configuration or action on your part.  We’re excited to offer this feature to you and look forward to hearing your responses, questions, and feedback.

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  1. […] Edge Purge – Allows customers to quickly edit or delete content on the edge server •    HTTP Compression – Simple, cost saving process allowing compressed objects to be downloaded more quickly •    […]

  2. CloudFiles is also compressing “application/javascript” content type, however this is not good because Internet Explorer < v9 does not support "application/x-javascript" nor "application/javascript".

    Only "text/javascript" is supported in IE 6, 7, 8.

    Can you extend this list to "text/javascript"?

  3. It would be great if the MIME types “text/javascript” and “application/javascript” were also added to the list of those compressed as mentioned by Andriy.

    There are 3 types being used today:
    “text/javascript” – Obsolete (still in widespread use for backwards compatibility)
    “application/x-javascript” – Experimental for the transition
    “application/javascript” – Official MIME type for Javascript

    However, the ‘type’ attribute is not explicitly required in the tag for HTML5 (at this stage!) which will potentially cause more problems.


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