All TCP/IP networks require an IP address for each device on the network. The version we have used since the beginning of the Internet is known as an IPv4 address. In this section we’re going to look at the “next generation” address protocol called IPv6, how it differs from IPv4, and why it’s become so important as the Internet continues to grow.
Think of every road, street, highway, or path you’ve ever been on and now imagine there is another road, street, highway, or path directly underneath that not too many people know about. Now imagine that there is another 340 undecillion more of those roads, streets, highways, and paths. That is IPv6 in a nutshell.
IPv6 was created due to the lack of available IPv4 addresses. With an additional 96 bits, it is 4 times the IP space of IPv4. We are allowed these additional addresses since IPv6 addressing uses hexadecimal characters.
IPv6 has been around since 1994 and it has been enabled, by default, on all Windows operating systems since Windows Vista. It is like having another door on your home that you see occasionally but never open. Well, that door would still lead an insider into your home. Now imagine that door being an address on your computer or mobile device.
Next time you are at the command prompt type ipconfig or ifconfig to see your current IP address. Most likely, you will see an IPv6 address with the prefix of FE80. That address will allow the same capabilities as the more common IPv4 address.
IPv4 and IPv6 are two separate protocols. It’s like having the ability to speak two different languages. These protocols DO NOT communicate with each other without some type of translation or tunneling mechanism. Currently there are over 30 different types of tunneling with Microsoft’s Teredo Tunneling being the most popular.
IPv6 Fun Facts:
- There are more IPv6 Addresses than there are grains of sand in the world!
- Facebook’s IPv6 address for their website contains face:b00c
- The full address is 2a03:2880:f103:83:face:b00c:0:25de
- You can find this (or any other IPv6 address) very easily:
- Windows: nslookup www.facebook.com
- Linux: host www.facebook.com
- Packet Pushers IPv6 Buzz (Podcast)
- Google IPv6 Statistics
- Microsoft – About Teredo
- RFC 8200: Internet Protocol, Version 6 (IPv6) Specification
- RFC 4443: Internet Control Message Protocol (ICMPv6) for the Internet Protocol Version 6 (IPv6) Specification
- RFC 4861: Neighbor Discovery for IP Version 6 (IPv6)
- RFC 4862: IPv6 Stateless Address Autoconfiguration
- RFC 3596: DNS Extensions to Support IP Version 6
- RFC 3315: Dynamic Host Configuration Protocol for IPv6 (DHCPv6)
- RFC 7381: Enterprise IPv6 Deployment Guidelines
- RFC 6555: Happy Eyeballs: Success with Dual-Stack Hosts
- Wikipedia – List of IPv6 tunnel brokers
- Basic IPv6 Pentesting