Client Server and Peer to Peer Networks

• What do servers do in general

  • A server controls access and security to one shared file store 
  • A server manages access to The Internet 
  • A server manages printing jobs 
  • A server provides email services 
  • A server runs a backup of data
• Components of a client server network

  • A client-server network is made up of a server and clients 
  • The client-server network is managed by a server  
  • The devices connected to the server are the clients 
  • Files and software are usually stored centrally on the server , rather than on individual client devices

  
• The client-server relationship

  • Clients send requests to the server e.g. asking for data  
  • The server processes the request and responds 
  • This is the client-server relationship

  
• How the server controls access

  • The server stores user profiles , passwords and access information 
  • It may request a password before fulfilling certain requests or deny requests to users without the right access level
• How the Internet uses client-server networks : websites and web-servers

  • Most uses of the Internet work on a client-server relationship 
  • For example, websites are hosted on web servers 
  • Web browsers are client programs which send requests to web-servers 
  • Web servers fulfil requests (e.g. by sending web pages) for thousands (or hundreds of thousands) of clients
• Peer to peer networks

  • In Peer-to-Peer (P2P) networks, all devices are equal , connecting directly to each other without a server 
  • You store files on individual devices and share them with others 
  • You may use a Peer-to-Peer network at home to share files between devices , or connect devices to a printer