IPv6

Paul Zimmerman · ‎07-11-2023

For today's Trivia Tuesday, the topic is IPv6. After all of this time, there is plenty of trivia associated with this concept! I worked on an IPv6 knowledge base portal for Cisco back in 2011, and at the time, it seemed like IPv4 had a very limited amount of life left in it. However, 12 years later, IPv4 is still very much in use. What's up with IPv6?

What is IPv6?

Internet Protocol version 6 (IPv6) is the communications protocol used to identify computers on networks and is used to route traffic on the Internet. Its predecessor, IPv4, was introduced in 1980, but as time went on, experts determined that with all of the new devices coming online, the world would eventually run out of IPv4 addresses. The original IPv6 specification was introduced to the IEFT in 1995 as RFC 1883, and adopted as a standard in 1998. The most current approved version of IPv6 is RFC 8200.

The number of addresses that IPv6 adds to the pool is quite impressive. IPv4's address space was 32-bit (2³²), which allowed for 4,292,967,296 unique IP addresses that could be assigned to hosts. IPv6 uses 128-bit addresses (2¹²⁸), which allows 3.4x10³⁸ unique IPs, or 340 undecillion (a trillion trillion trillion). That should last for a while!

IPv6 has several things that make it different than IPv4, including:

IPv4 addresses were 4 octets in decimal notation. IPv6 addresses are 8 groups of 16 bits in hexadecimal notation
DHCP is no longer used in IPv6. Instead, IPv6 uses Stateless Address Autoconfiguration (SLAAC) for stateless devices or DHCPv6 stateful devices.
Subnet masks are built into IPv6 addresses

Trivia question for the curious community... what happened to IPv5? Please share below!

Adoption

Google reports that as of last Friday, IPv6 adoption stands at 44.46%. This seems a bit slow, as the "World IPv6 Launch" was held way back in 2012. How bad is the problem? ZDNET reported that Europe ran out of IPv4 addresses in 2019, and just this year, the regional IP address controller in Asia was accused of using bullying and intimidation over IPv4 address allocation. If things are getting this bad, why is IPv6 adoption so slow?

Service providers have been pretty active in deploying IPv6, and countries in Asia and South America have also jumped in. However, many companies have been slow to make the change, and RIPE Labs found that IPv6 use actually dropped in the US between 2020 and 2021, which they postulated was related to returns to office after COVID. Cisco and others have implemented different IPv6 transition methods such as dual-stack to handle both types of traffic while the industry is in transition. In the meantime, several developers are trying to find ways to reuse or enhance existing IPv4 addresses to put off the impending conversion.

What are your thoughts on IPv6 adoption? Are we moving fast enough?

IPv6 and Network Automation

For us developers, the transition from IPv4 to IPv6 provides many opportunities to explore the use of network automation. Scott Hogg wrote about 10 tasks for IPv6 application developers. In addition to expected topics like IPv4/IPv6 compatibility, he also looked at using higher-level APIs that are IPv6-capable and provided the RFCs for those APIs.

Another example is how IPv6 can be used in building applications for IoT. IPv6 provides a ton of space to address mobility and location awareness needs. Also, security, privacy, and inoperability features are all supported by elements of IPv6.

Any of our community members want to discuss how IPv6 has impacted them as a developer?

davidn# · ‎07-11-2023

I tempted to convert my home lab to all IPv6 but a lot of devices around the house are still limited to IPv4 addresses. I think my ISP is IPv6-capable. My access point also supports IPv6. There are many ways that you can check if your devices support IPv6. Run ifconfig -a or netstat -nr and look for inet6 or Internet6. You can also use Ping6 (Mac/Linux) or ping -6 (Windows) to see if you can communicate with a target site via IPv6.

npetrele · ‎07-12-2023

Network Address Translation (NAT) makes IPV6 superfluous for most homes and small businesses. I can have a ton of IPV4 devices in my home without needing to register an IPV4 address that would take up a spot in the available addresses. Indeed, NAT is a layer of protection, too, since my local NAT addresses are not visible to the Internet.

shmcfarl · ‎07-14-2023

IPv5 was reserved for the Internet Stream Protocol which never made it off of the ground. It was never publicly usable and died in the draft stage. IPv6 was the next in line. Long live IPv6!

Lazarus_telecomTech · ‎12-19-2023

The notation of IPvX, where X is the version of the protocol, comes from the actual version number that appears in the "version" field of the IP packet header. Version number 5 was reserved in the 1990s for a now-defunct experimental stream protocol. T. Since it has already been defined, and to avoid any confusion, designers were forced to skip the use of "5" and use IPv6. Find out much more about it in this video: