I find it simple. Have a CDN edge server near the user, cache the request and when next time he asks for it, give it. But I am pretty sure what I am thinking, although correct, isn't complete and there is something missing.
My book has just included some small benefits of CDN, that's all. But that too isn't given in detail with illustrations(although it is not necessary i feel). Exam questions of mine has asked like how CDN reduces delay in received requested object for 8 marks(3hrs exam, 80 full marks).
The answer to this is literally 1 line ie the definition of CDN. and maybe 2 figures showing how it works with and without CDN. another question asked in the exam is-: how proxy CDN works, explain with example.
I am not sure how the updating of content happens.
Does only 1 proxy server gets updated or do all proxy servers get updated when 1 CDN brings a fresh copy of the web page from the origin server? It is confusing; believe me, the tutorials for this thing are advertisements for various CDNs.
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