When you plan your network addressing scheme, consider the following factors:
Type of IP address that you want to use: IPv4 or IPv6
Number of potential systems on your network
Number of systems that are multihomed, or routers, which require multiple network interface cards (NICs), each with individual IP addresses
Use of private addresses on your network
Use of a DHCP server to manages pools of IP addresses
For an introduction to IP addresses, refer to available articles about the topic online such as the following resources:
http://tools.ietf.org/html/rfc4291IP Version 6 Addressing Architecture
To obtain IP addresses, register with any Internet Service Provider, or through IANA's Internet Registries. See IANA's IP Address Service page (http://www.iana.org/ipaddress/ip-addresses.htm).
To show a subnet, the block is divided into multiple subnets by borrowing enough bits from the host to create the required subnet. For example, host address 192.0.2.0 might have subnets 192.0.2.32/27 and 192.0.2.64/27.