IPv4 vs IPv6
IPv4 and IPv6 are two address systems used on the internet; IPv6 was designed to provide far more addresses than IPv4.
How it works
IPv4 addresses look like 203.0.113.10 and have a limited address space. IPv6 addresses use hexadecimal groups, such as 2001:db8::1, and support a vastly larger pool. Most modern networks run both during a transition period. A website may reach your connection over IPv4, IPv6, or whichever route works best. VPN and privacy tools need to handle both protocols if your network uses both.
A dual-stack service may publish both an A record for IPv4 and an AAAA record for IPv6. Your device and network choose a route according to availability and performance. That can make a problem appear only on one protocol family.
For example, a VPN may show a changed IPv4 address while a website still reaches an IPv6 path outside the tunnel. The meaningful question is whether that behavior matches the VPN configuration you intended, not whether IPv6 exists at all.
Practical guidance
- Check whether your connection reaches a site over IPv4 or IPv6 before troubleshooting a VPN or firewall.
- Do not disable IPv6 merely because it is unfamiliar; first understand whether your network or VPN supports it.
- When reporting a connection issue, say whether it occurs on IPv4, IPv6, or both.
Common question
Is IPv6 more private? Not automatically. It has different addressing behavior, but privacy depends on the network, browser, VPN, and service involved.