What is an IP Address
An IP (Internet Protocol) address is a unique number that is assigned to each computer (or other device) that participates in a network. This number is used to identify and locate each device. Each device that participates in the network needs one or more IP addresses. For home or business networks, a DHCP service is usually used to automatically assign unique IP addresses to each device. IP address can also be assigned statically - which means that the device is specifically configured to use a designated IP address.
There are two versions of IP addresses in use on the internet. These are the IPv4 and IPv6 addresses.
A version 4 IP address (or IPv4 address) is a 32-bit number that is usually represented in chunks of 4 8-bit decimal bytes seperated by dots (.). For example, 220.127.116.11.
A version 6 IP address (or IPv6 address) is a 128-bit number that is usually represented in chunks of 8 hexadecimal 16-bit words, seperated by colons (:). For example, 2001:0500:0088:0200:0000:0000:0000:0010.
For ease of use, IPv6 addresses can be abbreviated to a shorter representation. Firstly, leading zeros can be omitted from each hexadecimal word. Secondly, one group of consecutive words that are all zero can be replaced by a double colon (::) - but note that this can only be done once, and only on one group of zeros.
For example, take the the following IPv6 address:
By removing leading zeros, this address becomes:
By replacing the group of consecutive zeros with a double colon, the address becomes:
In this case, the abbreviation makes the address slightly less than half the length of the full address.