The IP address planning is very important for implementing a small network. All hosts within the small network should have a unique address. The IP addressing scheme must be planned and documented. The IP addresses should be maintained based on the type of device configure the addresses. The different types of devices that required IP addresses are:-
- End devices
- Intermediary devices
- Hosts that are accessible from the Internet
The Figure below illustrates the devices which require IP address Planning to assign an IPv4 address.
Proper planning and documentation of the IP addressing are necessary for helping the network administrator to track device types and troubleshoot. Usually, the network administrator knows the ranges of IP addresses assigned to devices. For examples, if all hosts are assigned the IP address range from 100 to 200 and the servers are assigned an IP address between the range of 220 – 250; so it is easy to identify the traffic by IP address; and it is very useful when troubleshooting the network traffic issues using a protocol analyzer.
If IP address scheme is documented, the network administrator can easily control access to the resources available on the network. The IP addressing scheme is important for hosts that providing resources to the internal and external network such as e-commerce servers. Without proper planning, the security and accessibility are not possible. If a host has a random address assigned from address range, blocking access to this host is difficult. Different device types should be assigned a logical block of addresses within the address range of the network.
When you are a network administrator and want to set up a small network; If you only have a few computers. You maybe assign your network private IP addresses from the 192.168.0.0 to 192.168.255.255 range. There are sufficient addresses available for a small network. If your computer needs to access the internet, you may require public IP address. The public IP address you must purchase from ISPs.