Do i need a Content Delivery Network If my audience is in one city?

So ive asked question earlier about having some sort of social network website with lots of images and the problem is the more users , the more images the website will have and i was afraid it would take a LONG time for the images to load on the client side.

How to handle A LOT of images in a webpage?

So the feedback i got was to get a content delivery network. Base on my limited knowledge of what a content delivery network is, it is series of computures containing copies of data and clients access that certain servers/computers depending where they are in the world? What if im planning to release my website only for a university, only for students. Would i need something like a CDN for 开发者_Go百科my images to load instantly? Or would i need to rent a REALLY expensive server? Thanks.

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The major hold up for having lots of images is the number of requests the browser has to make to the server, and then, in turn, the number of requests the server has to queue up and send back.

While one benefit of a CDN is location (it will load assets from the nearest physical server) the other benefit is that it's another server. So instead of one server having to queue up and deliver all 20 file requests, it can maybe do 10 while the other server is simultaneously doing 10.

Would you see a huge benefit? Well, it really doesn't matter at this point. Having too much traffic is a really good problem to have. Wait until you actually have that problem, then you can figure out what your best option is at that point.

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If you're target audience will not be very large, you shouldn't have a big problem with images loading. A content delivery network is useful when you have a large application with a distributed userbase and very high traffic. Underneath that, and you shouldnt have a problem.

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Hardware stress aside, another valuable reason for using a CDN is that browsers limit the number of simultaneous connections to one host, so let's say the browser is limited to 6 connections and you have in one page load 10 images, 3 CSS files and 3 javascript files. If all 10 of those images are coming from one host, then it will take a while to get through all 16 of those connections. If however, the 10 images are loaded from a CDN that uses different hosts, that load time can be drastically reduced.

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Even if all your users are geographically close, they may have very different network topologies to reach your hosting provider. If you choose a hosting provider that has peering agreements with all the major ISPs that provide service in your town, then a CDN may not provide you much benefit. If your hosting provider has only one peer who may also be poorly connected to the ISPs in your town, then a CDN may provide a huge benefit, if it can remove latency from some or all of your users.

If you can measure latency to your site from all the major ISPs in your area to your hosting provider, that will help you decide if you need a CDN to help shorten the hops between your content and your clients.