The IP address is divided into the Net-ID and the Host-ID. The Net-ID is required for addressing the network and the Host-ID for addressing the network subscriber within a network.
A committee (InterNIC) assigns a free Net-ID for networks which are to be connected directly to the Internet. You can found out the Net-ID from the network administrator.
The assignment of the Host-ID is free to select by the user. You must make sure that the IP address is unique. The Host-ID should be assigned in consultation with the network administrator.