On April 15, 2011, the internet officially ran out of IPv4 addresses, and people were terrified. “Since we’ve run out of IPv4 addresses, what will happen to our websites?” “Does this mean we shouldn’t bother getting web hosting?” “But I just registered my domain! Did I just waste my money?” These were some of the questions being screamed by scared webmasters.
But, as it turns out, IPv6 isn’t scary at all. In fact, there are several advantages of IPv6 to IPv4. And in this guide, we’ll walk you through them.
But just so we know we’re on the same page…
Table of Contents
What’s an IP address?
An IP address is a numerical label assigned to every device that’s connected to the internet. Having an IP address allows a device to communicate with other devices that also have an IP address.
What is IPv4?
IPv4 stands for “Internet Protocol version 4”. It’s the original format for IP addresses, and it allowed for 4 billion unique IP addresses. That seemed like a lot of IP addresses in 1981 when there were relatively few devices that could connect to the internet. But now, not only do most people have multiple computers connected to the internet, but there are also smart cars, smart TVs and even smart refrigerators with IP addresses. No wonder we ran out!
What is IPv6?
IPv6 is the IP address format that was designed to supplement IPv4.
Comparing IPv6 to IPv4
- IPv4 is a 32-Bit IP address whereas IPv6 is a 128-Bit IP address. This means it’ll take a lot longer to run out of IPv6 addresses than it took for us to run out of IPv4 addresses.
- IPv4 is a numeric addressing method while IPv6 uses an alphanumeric addressing method. This is another reason it’ll be harder to run out of IPv6 addresses.
- IPv4 includes checksum fields and IPv6 has none. Most technology already has checksum and error-control capabilities. Getting rid of IP-level checksum means that the checksum doesn’t need to be recalculated at every router hop.
- IPv4 employs ARP (Address Resolution Protocol) to map to MAC address while IPv6 uses NDP (Neighbour Discovery Protocol) to map to MAC address. The Secure Neighbour Discovery (SEND) protocol can enable cryptographic confirmation that a host is who it claims to be at connection time. This makes Address Resolution Protocol (ARP) poisoning and other naming-based attacks more difficult.
- IPv4 binary bits are separated by a dot whereas IPv6 binary bits are separated by a colon. This means IPv4 addresses typically look like this 121.54.021 while IPv6 addresses typically look like this 2012:6578:6574: :7658.
See? Not so scary after all. And now that you understand a bit more about the comparisons of IPv6 to IPv4, what are the advantages of IPv6 to IPv4?
6 advantages of IPv6 to IPv4
1. Simpler header format
IPv4 offers 12 header fields whereas IPv6 offers 8 header fields. The introduction of extension headers makes it possible to implement optional information into IPv6 packages much more effectively than with IPv4. Because routers on the delivery path of a package don’t process IPv6 extension headers, with IPv6, these are only read at the destination, which means a significant improvement of router performance.
2. More efficient routing
IPv6 reduces the size of routing tables, which makes routing more hierarchical and therefore more efficient. IPv6 also lets ISPs combine the prefixes of their customers’ networks into a single prefix. Additionally, with IPv6, the source device, rather than the router, handles fragmentation, using a protocol for discovering the path’s Maximum Transition Unit (MTU).
3. More security
Because IPv6 uses 128-bit addresses, the pool of possible addresses is 340 undecillion (3.4×1038). IPv4’s 32-bit addresses allow for only 4.3 billion addresses. A bigger pool of addresses obviously means more scalability, but, less obviously, it also means increased security. That’s because under the IPv6 system, host scanning and identification is more difficult for hackers.
When IPv4 was first developed, internet security wasn’t as much of an issue as it is today. This explains why the few security protocols available for IPv4 appear to have been developed as an afterthought. But IPv6 was built with security in mind. Many of the IPv4’s optional security requirements have been baked into IPv6 as default requirements. For instance, IPv6 automatically encrypts traffic and checks packet integrity. This gives standard internet traffic VPN-level protection.
4. True Quality of Service
Quality of Service (QoS) is a tool that lets you train your router to allocate specific portions of your available bandwidth to different applications. Good Quality of Service means, for example, your computer won’t struggle to play a video because it happens to be trying to download a massive file at the same time.
Quality of Service technically exists in IPv4, but it doesn’t actually work. Packets can technically be assigned different priorities, but routers usually just ignore the QoS flag, and some even mark all packets “Highest priority”, which, as you might imagine, defeats the purpose.
But IPv6 has an integrated mechanism for securing Quality of Service. It prioritises urgent packages, which makes handling those packages more efficient. It even has specialised fields (“traffic class” and “flow label”) that are directly responsible for ensuring Quality of Service.
5. Easier file-sharing
With IPv6, there are two separate address spaces for private addressing. These are called “link-local” and “site-local”. A link-local address has lots of useful functions, including hosting auto configuration by simply querying the router (no DHCP necessary!) and setting up ad-hoc LANs without a router. This means you can connect PCs and share files without having to bother with file-sharing protocols.
6. No more NAT (Network Address Translation)
Because there aren’t enough IPv4 addresses, much of the internet relies on NAT for connectivity. NAT was great for extending the life of IPv4, but it also forces every packet that enters or leaves your network to be examined and altered. And services that use multiple ports have a particularly hard time, since they need to undergo all sorts of cumbersome adjustments to work. With IPv6, every device can have its own unique IP address, which eliminates the need for NAT!
Understanding IPv6 helps us make better decisions, such as whether we should go ahead and create that website we’ve been dreaming about (Yes!) and whether we should be staging protests to prolong the life of IPv4.
It is becoming increasingly difficult to add resources to the Internet via IPv4 addresses as they are rare. IPv6 connections can only be useful if Web content also is available via this protocol. This means that each party within the network will need to migrate to IPv6 if more websites are enabled.