IP (Internet Protocol) Address is an identifier for a computer or device on a TCP/IP network. Networks using the TCP/IP protocol route messages based on the IP address of the destination.
Although IP addresses are stored as binary numbers, they are usually displayed in human-readable notations, such as 22.214.171.124 (for IPv4 ), and 2001:db8:0:1234:0:567:1:1 (for IPv6 ). Current IP Address in use is IPv4.
Static and Dynamic IP Address
When network infrastructure devices such as servers, routers and firewalls are to use the same IP address each time it powers up, this is known as a Static IP address. In contrast, in situations when the IP address is assigned automatically, it is known as a Dynamic IP address. Cable and DSL modems typically use dynamic IP with a new IP address assigned to the modem each time it is rebooted.
Private and Public IP Address
An IP address can be Private , for use on a LAN, or Public , for use on the Internet or other WAN.
Early specifications intended IP addresses to each be uniquely assigned to a particular computer or device. However, it was found that this was not always necessary as private networks developed and address space needed to be conserved (IPv4 address exhaustion). RFC 1918 specifies private address spaces (also known as non-routable addresses) that may be reused by anyone; today, such private networks typically connect to the Internet through Network Address Translation (NAT). In addition, technologies such as anycast addressing have been developed to allow multiple hosts at the same IP address but in different portions of the Internet to service requests by network clients.
The Internet Assigned Numbers Authority (IANA) manages the global IP address space. IANA works in cooperation with five Regional Internet Registries (RIRs) to allocate IP address blocks to Local Internet Registries (Internet service providers) and other entities.
|IANA Reserved Private Network Ranges||Start of range||End of range||Total addresses|
|24-bit Block (/8 prefix, 1 x A)||10.0.0.0||10.255.255.255||16,777,216|
|20-bit Block (/12 prefix, 16 x B)||172.16.0.0||172.31.255.255||1,048,576|
|16-bit Block (/16 prefix, 256 x C)||192.168.0.0||192.168.255.255||65,536|