What is Peer to Peer Network Architecture?

          For example take  above image,The above server is a web server for the website called www.bittorrentz.com. just a assume that bittorrent is announced that it is going to publish a new movies with free of cost for anyone who want it.But it will be removed within a day.After that  all people will wait for that movie file will be appear. once if the file updated then all the users will try to download a same file at simultaneously,then the bittorrentz server will be busy for responding to all clients or it may go down because of over load and heavy network traffic.  

         So here they found some solutions to prevent the web server from heavy traffic or collapse by using peer to peer network.That is instead of sending files to all the clients the bittorrentz server will send the data to some of the clients.Then the remaining few clients who wants the file that can be download from another client who already download it.The bittorrentz is working same file sharing method.it provides the anonymized routing of network traffic.

        This network is desinged for small type of networks such s home,or small office setups where the dedicated server is not required.Why bacause there is a small office.they re not willing to spend money for a server. But they want to share their reources over the network.When there is no dedicated server then all the nodes in the network will be treated as same.capability hence the term 'PEER'.