IPv6
IPv6 (Internet Protocol version 6) is the sixth version of the Internet Protocol, designed to replace the aging IPv4 and solve the problem of IP address exhaustion. Adopted as a standard in 1998, IPv6 provides an almost unlimited number of unique addresses using 128-bit addressing (around 3.4 × 10³⁸ combinations).
IPv6 not only expands address space but also enhances security, routing efficiency, and overall Internet functionality.
IPv6 Address Format
An IPv6 address is written as eight groups of hexadecimal numbers separated by colons, for example:
2001:0db8:85a3:0000:0000:8a2e:0370:7334
To simplify notation, leading zeros can be omitted, and consecutive zeros can be replaced with ::.
Key Features of IPv6
- 128-bit addressing – practically unlimited number of unique addresses.
- Autoconfiguration (SLAAC) – devices can self-assign IPv6 addresses without DHCP.
- Built-in security – IPsec support is mandatory for all implementations.
- Simplified routing – more compact packet header structure.
- No need for NAT – every device can have a unique global address.
Problems Solved by IPv6
- shortage of IPv4 addresses;
- complexity of NAT and CG-NAT;
- growing demand from IoT, mobile devices, and sensors;
- need for higher security and network transparency.
Applications
IPv6 is being gradually adopted in global networks:
- supported by most Internet providers;
- used in mobile networks (4G, 5G);
- applied in IoT devices requiring unique IPs;
- deployed in enterprise networks for future-proof compatibility.
Example
A user connects to a 5G network, and their smartphone receives an IPv6 address. The device can now exchange data directly with servers without NAT, simplifying connections and improving application performance.
Frequently Asked Questions (FAQ)
IPv6 solves the address shortage problem, provides built-in IPsec security, simplifies routing, and allows every device to have a unique global address.
It consists of eight groups of hexadecimal numbers separated by colons, e.g., 2001:db8::1. This format is much longer than IPv4.
Yes. Most modern networks operate in dual-stack mode, supporting both protocols simultaneously for compatibility.
Many networks and applications are still based on IPv4, and migration requires upgrading hardware and software. This makes the transition gradual.
In most cases, no. Modern devices and ISPs support IPv6 automatically, so connections work without user intervention.
