IPv6 (Internet Protocol version 6) is a revision of the Internet Protocol (IP) developed by the Internet Engineering Task Force (IETF). IPv6 is intended to succeed IPv4. The reason for the need for succession is simple: the demand for IP addresses is too great. For many years the industry has managed with IPv4 through the use of network address translation (NAT), the process of modifying IP address information in IP packet headers while in transit across a traffic routing device.
This is what allows one to have many devices connected to one router. The router has its own IP address, such as 192.168.0.1, and assigns other (non-public) IP addresses to connected devices (desktop, laptop, printer, etc.). The analogous topology in wireless is that the GGSN (Gateway GPRS Support Node) maintains a static IP address and the SGSN (Serving GPRS Support Node) provides IP addresses upon connecting to mobile cellular phones requesting a cellular data connection.
This is great so long as one can connect to a router of some type relying upon it to provide an IP address on demand. This falls short in a world of numerous devices, or even non-telecom assets, which require an IP address, and connect to a network in a non-traditional manner. This is the direction that the world is going in which there will be many items/things that require an IP address that go way beyond traditional IP telephony.
Unlike IPv4, which has relatively easy to remember numbers such as Comcast’s IP address 192.168.0.1, IPv6 numbers can be much larger and very hard to remember such as IPv6 addresses, as commonly displayed to users, consist of eight groups of four hexadecimal digits separated by colons, for example 2001:0db8:85a3:0042:0000:8a2e:0370:7334. It is easy to see that the new addressing scheme for IPv6 provides for many more IP addresses than would be available through IPv4.
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