|  | 10.1 | IP Addressing and Subnetting
| 10.1.1 | The purpose of IP address
In a TCP/IP environment, end stations communicate with servers or other end stations. This can occur because each node using the TCP/IP protocol suite has a unique 32-bit logical address. This address is known as the IP address and is specified in 32-bit dotted-decimal format. Router interfaces must be configured with an IP address if IP is to be routed to or from the interface. ping and trace commands can be used to verify IP address configuration. Each company or organization listed on the Internet is seen as a single unique network that must be reached before an individual host within that company can be contacted. Each company network has an address; the hosts that live on that network share that same network address, but each host is identified by the unique host address on the network.