There is a quite straightforward and effective strategy I've used with my Vbulletin forum. I will be repeating it for the IBP forum I am migrating to.
This crowd offers a great CDN service that is very easy to setup. www.simplecdn.com is who I've been using for a couple of months now. They start of by giving you 15$ worth of credit to experiment with. Once you are happy you can apply for a CNAME extension, these actually cost $25SUD and it's the point where you have to part with money.
Since July it has cost me 100$ (added to account) however I have 77$ left on my account, you have to prepay before your 15$free runs out. I've just paid a transit charge of 0.38$ for 9.78Gb of usage.
I'm using a mirror bucket and you can vary the cache time, it's really simple, you change the asset url e.g. js or css to there server. The first time the asset is requested, the mirror will connect and cache the file and then serve the file, thereafter it's all on there cache till it expires.
You can also use both gzip and non-gzip'd mirrors along with different hour caches settings, for example:
1 Hour Expire; gzip Enabled 1 Hour
http://xxx.lg1x3z.simplecdn.net/ 3 Hours Expire; gzip Enabled 3 Hours
http://xxx.lg1x4z.simplecdn.net/ 6 Hours Expire; gzip Enabled 6 Hours
http://xxx.lg1x5z.simplecdn.net/ 12 Hours Expire; gzip Enabled 12 Hours
http://xxx.lg1x6z.simplecdn.net/ 24 Hours Expire; gzip Enabled 24 Hours
http://xxx.lg1x8z.simplecdn.net/ 7 Days Expire; gzip Enabled 7 Days
for images with IPB it appears you could edit the image url in general config (v3.0.#) for other assets css, js and so on there might be a little more editing to be done.
I'm working (as always) on optimizing the user experience for several Invision boards that we manage.
One option I am looking at is to have static (or rarely changed) files such as CSS, IPB and IP Gallery image files hosted on a content distribution network such as Akamai, Edgecast or Amazon Web Services CloudFront.
Has anyone undertaken such an initiative and have any guidance to share in terms of the best practices for doing this optimally for IPB and IPG?
