#vision is "share in the sum of all knowledge" and all our projects contain a wealth of information. The infra structure, the software that brings this information is at this time very much centred on the two ends of delivery. It is in the data centres and it is in the last mile.
The effort of the last mile is the Wikipedia Zero project; This wonderful project brings information at no cost to the mobile phones of people who use the services of cooperating mobile operators. The content they use comes from the WMF datacentres in the USA and, that is suboptimal.
It is suboptimal because it takes time to get that data from the first world data centres of the WMF. It is suboptimal because the pipes are often oversubscribed. The consequence is that the service is not as good as it easily could be.
With a "content delivery network", this information is kept locally and it is only the updates that have to come and go all the way to the central servers in the USA. This is a lot less data for those pipes, it is a lot cheaper to operate for our cooperating mobile operators in Wikipedia Zero and the quality of service will improve a lot.
There are no technical reasons why the WMF cannot do this. All that I see is personal preferences and possibly some legal issues. The WMF has the experience because of its servers in Amsterdam. It should be relatively easy to mimic this at the sites of our cooperating mobile operators. Alternatively we could pay commercial rates and do it ourselves.
A lot of effort is invested in making Wikipedia, MediaWiki perform better. This is another obvious improvement that will make a big difference not only to our Wikipedia Zero users but for everyone who uses our projects outside of the USA and much of Europe.