"Two Part" Addresses

• The network part is the same for all hosts connected to the same network. The network part is used to route datagrams across the Internet.
   
  
  • Every network in the global Internet has a unique network identification number.
     
    
• The host part must be unique within each specific network. It is used to deliver the datagram once it has been routed to the appropriate network.
   
  
  • The combination of the unique network number plus a "host-within-network" number means that every Internet-connected computer has a globally unique IP address.