IPv6 addresses can be daunting at first glance. A typical address – 2001:0db8:85a3:0000:0000:8a2e:0370:7334 – looks nothing like the familiar 192.168.1.1 format most of us recognise.
These lengthy strings of letters and numbers aren’t designed to be difficult. They’re the solution to a critical problem that’s been building for decades: the internet has run out of addresses.
This guide explains why IPv6 exists, why it’s becoming increasingly relevant for UK businesses, and how to understand those address formats that initially seem complex.
What Is IPv6?
IPv6 stands for Internet Protocol version 6. In simple terms, every device that connects to the internet requires an address, similar to how every property requires a postal address for mail delivery.
IPv6 is the current system for assigning these addresses. It’s the successor to IPv4 (Internet Protocol version 4), which has been the foundation of internet communication since the early 1980s. Both protocols serve the same purpose – they identify devices on a network and ensure data reaches the correct destination. IPv6 simply operates with a significantly larger address space.
The scale is substantial: IPv4 uses 32-bit addresses, providing approximately 4.3 billion possible addresses. IPv6 uses 128-bit addresses, which delivers 340 undecillion addresses – that’s 340 followed by 36 zeros. To provide perspective, there are enough addresses to assign billions to every person on Earth whilst still having vast reserves remaining.
Why Was IPv6 Created?
The fundamental issue is straightforward: the global pool of IPv4 addresses was exhausted over a decade ago.
When IPv4 was designed in the early 1980s, 4.3 billion addresses appeared more than adequate. The internet was primarily a research network connecting universities and government institutions. Personal computers were uncommon, and the explosion of smartphones, tablets, IoT devices, and other connected equipment hadn’t yet occurred.
By 2011, the Internet Assigned Numbers Authority (IANA) officially exhausted the global pool of available IPv4 addresses. By 2020, Europe’s regional internet registry had depleted its IPv4 reserves. Today, organisations requiring IPv4 addresses must either recycle existing addresses or purchase them on the secondary market, often at considerable cost.
The growth of connected devices has accelerated this shortage. Every smartphone, laptop, security camera, and IoT sensor requires an IP address. The Internet of Things alone has added billions of devices to global networks, a scale that IPv4 simply cannot accommodate.
IPv6 development began in the late 1990s specifically to address this limitation. Design work started in 1994, with IPv6 becoming an official standard in 1998. The objective was clear: create an addressing system of sufficient scale to prevent future exhaustion, whilst also addressing several of IPv4’s technical limitations.
How to Read an IPv6 Address
IPv6 addresses appear complex initially, but they follow a logical structure. Once you understand the format and shortening conventions, they become considerably more manageable.
An IPv6 address consists of eight groups of four hexadecimal digits, separated by colons. Each group represents 16 bits, totalling the full 128 bits. Here’s a complete address:
2001:0db8:85a3:0000:0000:8a2e:0370:7334
Let’s examine what this represents:
Hexadecimal, Not Decimal
Unlike IPv4’s dotted decimal notation (192.168.1.1), IPv6 uses hexadecimal. That means each digit can be 0-9 or A-F (representing 10-15). This is more compact than decimal and works better with binary computer systems.
Eight Groups of Four
The address is split into eight sections (called hextets), each with four characters. This structure always adds up to 128 bits total.
The Address Structure
The address is divided into two 64-bit sections. The left half (first four groups) identifies the network, whilst the right half (last four groups) identifies the specific device on that network. This is comparable to a postal address where the town and postcode identify the general area, whilst the street and house number identify the specific location.
Shortening Conventions
To improve usability, two rules allow for address abbreviation:
Rule 1: Leading zeros may be omitted. The group “0db8” becomes “db8”, and “0000” becomes “0”.
Rule 2: Consecutive groups containing only zeros can be replaced with a double colon (::). This may only be done once per address to maintain clarity.
Applying these rules, the address above simplifies to: 2001:db8:85a3::8a2e:370:7334
Practical Example
Consider an address assigned by your ISP: 2601:5005:6006:f00d:0000:0000:0000:1234
Using the shortening rules: 2601:5005:6006:f00d::1234
The left portion (2601:5005:6006:f00d) is your network prefix, assigned by your ISP. The right portion (::1234, or fully written 0000:0000:0000:1234) identifies your specific device within that network.
Understanding this network:device pattern makes IPv6 addresses significantly more approachable.
Accessing IPv6 Addresses in Web Browsers
One practical difference between IPv4 and IPv6 addresses concerns web browser access. With IPv4, you can type an address directly into your browser: http://192.168.1.1
IPv6 requires a different format due to the colons already present in the address. Without modification, a browser cannot distinguish between the colons separating address segments and the colon separating the protocol from the address.
The solution is to enclose IPv6 addresses in square brackets:
http://[2001:db8:85a3::8a2e:370:7334]
Or for HTTPS:
If you’re accessing a specific port, the port number appears after the closing bracket:
http://[2001:db8:85a3::8a2e:370:7334]:8080
This bracket notation applies to any situation where you’re directly accessing an IPv6 address – whether for web interfaces, configuration pages, or internal systems. In practice, most users access services via domain names rather than IP addresses directly, so this distinction rarely affects day-to-day usage. However, it’s essential knowledge for system administrators and technical staff managing network infrastructure.
Benefits of IPv6 Over IPv4
Beyond the substantial increase in available addresses, IPv6 delivers several technical improvements:
Elimination of Network Address Translation
With IPv4, Network Address Translation (NAT) is widely used due to address scarcity. Routers use a single public IP address whilst assigning private addresses to internal devices. Whilst functional, this approach complicates hosting servers, online gaming, and peer-to-peer applications.
IPv6 provides every device with a globally unique address, removing the need for NAT. This simplifies network configuration and enables direct device-to-device communication.
Enhanced Routing Efficiency
IPv6’s address structure supports improved route aggregation, allowing routers to process traffic more efficiently. This reduces routing table sizes and accelerates packet forwarding across networks.
Built-In Security Features
IPv6 has IPsec (Internet Protocol Security) baked into the standard. While IPsec can be used with IPv4, it’s optional and often not implemented. With IPv6, the security framework is mandatory, making encrypted, authenticated connections more straightforward.
Automatic Address Configuration
IPv6 devices can automatically configure their own addresses when they connect to a network, without needing DHCP servers. This “stateless address autoconfiguration” makes network setup simpler, especially for large deployments or IoT devices.
Multicast Instead of Broadcast
IPv4 uses broadcast messages, which go to every device on a network even if most don’t need them. IPv6 uses multicast, sending messages only to devices that have joined specific groups. This reduces unnecessary network traffic and improves efficiency.
Better for Modern Applications
Technologies like 5G networks, IoT deployments, and smart cities are built with IPv6 in mind. These systems require massive numbers of connected devices and benefit from IPv6’s vast address space and improved efficiency.
Current IPv6 Adoption
IPv6 adoption has progressed steadily, though more gradually than initially anticipated. As of early 2025, global IPv6 traffic represents approximately 43-45% of total internet traffic according to Google’s measurements, though adoption rates vary considerably by region.
Regional Leadership
France and Germany lead European adoption with rates approaching 75-80%, driven largely by mobile network operators deploying IPv6 to new subscribers. India follows closely at 74%, whilst Belgium and Malaysia also demonstrate strong implementation. The UK’s adoption rate sits in the middle range amongst developed nations.
The United States, despite hosting numerous major technology companies, maintains an adoption rate just above 50%. Legacy IPv4 infrastructure and varying ISP priorities have contributed to this more measured pace.
Mobile Networks as Early Adopters
Mobile operators have been particularly active in IPv6 deployment. When implementing 4G and especially 5G networks, many chose to build on IPv6 infrastructure from inception rather than retrofitting IPv4. Operators such as Reliance Jio in India and major European carriers have been at the forefront of this transition.
Tech Giants and Cloud Providers
Major technology companies have implemented IPv6 across their services. Google, Microsoft, Facebook, and Amazon all support IPv6. Cloud hosting providers routinely offer IPv6 alongside IPv4.
Government and Enterprise
The US government has mandated IPv6 support for federal agencies. China has made IPv6 adoption a national priority, aiming to have the world’s largest IPv6 network. Many large enterprises, especially those deploying IoT devices or running modern datacentres, are moving to IPv6.
But IPv4 Isn’t Dead
Here’s the reality: IPv4 will be with us for years to come. Most networks run in “dual-stack” mode, supporting both protocols simultaneously. As long as IPv4 still works (thanks to technologies like NAT extending its life), many businesses see little urgency to switch entirely.
IPv6 in Our Managed and Hosted Services
At AOIT Networks, we provide both IPv4 and IPv6 addresses across all our managed and hosted services. This dual-stack approach ensures flexibility based on your specific requirements.
For most UK SMBs, IPv4 remains adequate for current operations. Standard business applications – websites, email, and office networks – function effectively on IPv4 for the foreseeable future. However, specific scenarios benefit from IPv6 capability:
Expanding Connected Device Infrastructure
If your organisation is deploying IoT sensors, expanding network capacity, or requires multiple public IP addresses, IPv6 addresses the scarcity issue without the complexity of NAT implementation.
Modern Cloud Deployments
Many cloud-native applications and microservices architectures are designed with IPv6 support. Organisations moving to containerised deployments or building new infrastructure gain additional flexibility with IPv6 availability.
Direct Device Communication Requirements
Applications requiring peer-to-peer connections – such as advanced video conferencing systems, VoIP infrastructure, or collaborative platforms – operate more efficiently with direct connectivity. IPv6’s end-to-end addressing model simplifies these implementations.
Infrastructure Future-Proofing
As internet infrastructure continues its gradual transition to IPv6, maintaining dual-stack capability ensures your organisation can adapt without urgent remediation. Having both protocols available provides operational flexibility as requirements evolve.
The approach is pragmatic: we don’t recommend IPv6 where it provides no advantage, but we ensure it’s available when your applications or partners require it. All our managed services and hosted environments support both addressing schemes, either individually or in parallel configuration.
Assessing IPv6 Requirements for Your Business
For most UK SMBs, immediate IPv6 implementation is not urgent.
If your current network operates effectively, you’re not experiencing address limitations, and your applications don’t specifically require IPv6, there’s no pressing need for transition. IPv4 remains viable, and dual-stack support across the internet means both protocols will coexist for the foreseeable future.
However, IPv6 awareness becomes relevant if your organisation is:
- Planning significant infrastructure upgrades or changes
- Deploying large numbers of connected devices or IoT systems
- Developing new applications or services
- Working with partners or clients who mandate IPv6 support
- Receiving guidance from your ISP or hosting provider regarding IPv6
The transition to IPv6 is evolutionary rather than revolutionary. Most modern operating systems (Windows, macOS, Linux, iOS, Android) support IPv6 natively. Contemporary routers and network equipment generally include IPv6 capability. The question centres on timing – determining when implementation makes sense for your specific circumstances rather than whether to adopt it at all.
Consider IPv6 as a planning consideration rather than an immediate concern. Ensuring your IT infrastructure can accommodate it when requirements emerge is prudent, but wholesale replacement of functioning systems is rarely warranted.