This page is provided as a very general overview for the average “person on the street”.
Ultimately (just like IPv4), the average user will not need to concern themselves about IPv6. Implementing IPv6 for your internet connection will be a job for your IT support company.

IPv6 will eventually replace IPv4 which is running out of IP addresses.

IPv4 (more commonly referred to as just "IP") is the familiar set of 4 octets, or "dotted decimal notation" - and are common examples of private (not directly addressable via the internet) IP addresses, while (one of our name servers) is a public (directly addressable via the internet) IP address.

Your firewall does a thing called “NAT” (Network Address Translation) to make your PC on your private network appear to be coming from the public IP address of your internet connection. IPv4 allows approximately 4 billion unique IP addresses.

One of the main ideas with IPv6 is that private addresses will no longer be used, NAT will no longer be required and everything can be directly addressable via the internet (not necessarily accessible as you will still need firewall rules to allow any external connections in). This will, among other things, help things like VoIP (Voice over IP) work easily and properly all the time, and remove the problem of VPN’s (Virtual Private Networks) requiring an end network to be renumbered because it clashes with another end network.

IPv6 is a set of 8 segments, or "colon hexadecimal notation" - 2001:0db8:1234:5678:9abc:def0:1234:5678.
Hexadecimal (also referred to as "hex”) combines 0-9 and the letters a-f to give a base 16 counting system.
Counting in hex looks like 1, 2, 3… 8, 9, a, b, c, d, e, f, 10, 11... 19, 1a, 1b, 1c, 1d, 1e, 1f, 20... 9d, 9e, 9f, a0, a1… fd, fe, ff, 100, 101... So 10 in hex is 16 in decimal, 100 in hex is 256 in decimal.

The IPv6 address is effectively chopped in half, with the first half (2001:0db8:1234:5678...) or the 64 bit “Network Identifier” used for "sub netting" (defining smaller chunks for routing to ISPs and customers), while the second half (...9abc:def0:1234:5678) or the 64 bit “Interface Identifier”, in conjunction with the Network Identifier, forms the IP address that will end up on your PC/printer/smartphone/VoIP phone/TV/fridge/freezer/toaster...

The average private IPv4 subnet is generally a "Class C" (192.168.1.xxx or similar) which allows 256 IP addresses, or a "Class A" (10.xxx.xxx.xxx) which allows approximately 16.8 million IP addresses.
The IPv6 allocation for an internal subnet (the Class A or Class C replacement) is referred to as a "/64", this allows approximately 2.6 billion IP addresses... For every man, woman and child on earth!

Xtreme will be routing a "/56" (which provides 256 /64's) to each internet connection we provide. This will allow a /64 subnet for your internal network and a “handful” (255) more /64's available for other things…

Having bogged you down with the numbers, the key thing with IPv6 is: Don't get bogged down in the numbers!

At the end of the day, we give you a silly number of IP addresses and you will use 14 or 130 or however many you need and will have plenty left!

How to shorten these unwieldy IPv6 addresses:

Leading 0’s are not required in a segment, so …:0130:… can simply be …:130:…

Segments with a value of “0000” can be shortened to 0, so …:0000:… can simply be …:0:….

Adjacent segments of “0000” (or “0”) can be replaced with a double colon “::”, so …:0:0:0:… can be replaced with …::…

As an example, an address of 2001:0db8:0010:0000:0000:0000:0000:0110 looks very cumbersome.

This can be shortened to 2001:db8:10:0:0:0:0:110, or shortened even further to 2001:db8:10::110, which makes it all seem so much easier!

Only one set of double colons can be used – 2001:db8::54::22 will not work as a shortened version of 2001:db8:0:0:54:0:0:22 because there is an unanswerable question of “How many 0 segments go in each ::?”. You would have to settle for either 2001:db8:0:0:54::22 or 2001:db8::54:0:0:22.