Two address systems can share the same connection
Seeing an unfamiliar address full of colons does not mean your home network has changed owners. IPv6 is an internet addressing system that can run alongside IPv4 on the same Wi-Fi or Ethernet connection. This arrangement is called dual stack. It does not require a second broadband subscription or a special Ethernet cable.
The useful question is whether IPv6 works beyond your home, not merely whether your computer lists an IPv6 address. This guide uses a personally owned Windows 11 PC and its built-in Command Prompt to separate those questions. The checks inspect configuration and send a few diagnostic packets; they do not change your router, firewall or address settings.
Start while ordinary browsing works, if possible. That gives you a baseline before investigating a fault. If a work VPN controls the connection, its routing may be part of every result. Use a personal PC for a household comparison rather than changing managed settings.
Read the address without decoding every digit
IPv6 uses 128-bit addresses, written in hexadecimal groups separated by colons. Double colons compress consecutive zero groups. For a hypothetical documentation example, 2001:db8:1234:1::25 and 2001:0db8:1234:0001:0000:0000:0000:0025 represent the same address. Neither is an address to copy into your network settings. The IETF addressing specification defines this notation.
- Link-local address
- An address such as
fe80::1serves the immediate network link. Routers do not forward it onto the internet. Its presence alone cannot establish internet access. - Global address
- This has a scope suitable for internet routing. Having one still does not prove that the route, provider service or remote destination works.
- Loopback address
::1means this computer itself. A successful ping to it does not test Wi-Fi or the internet.
Multiple IPv6 addresses on one interface are permitted. Do not delete addresses simply because there is more than one, or interpret their count as a count of connected computers.
Inspect the connection you are actually using
- Press Windows + R, type
cmd, and press Enter. Use the ordinary Command Prompt; these inspection commands do not need an administrator window. - Type
ipconfigand press Enter. Find the connected Wireless LAN adapter Wi-Fi or Ethernet adapter block. Adapter names can differ. Skip entries marked Media disconnected and avoid treating a virtual adapter as your household connection. - Within that block, note the IPv4 address, any IPv6 addresses and the Default Gateway. For more context, run
ipconfig /alland inspect the same adapter's DNS servers and configuration details.
Microsoft's current command reference explicitly applies to Windows 11. You may see both address families and more than one gateway line. An IPv6 gateway beginning with fe80: is not inherently wrong: the next router is on your local link even when the final destination is remote.
A Windows link-local address may end with a scope suffix such as %12, identifying the local interface. Preserve it if you later copy that address for a local diagnostic; it is not another hexadecimal address group.
Keep full output private. It can include public addresses, adapter identifiers and local naming information. For a support request, extract the relevant adapter's results and redact unrelated identifiers. Do not publish a full configuration dump just to ask whether IPv6 is working.
Test a path rather than trusting a label
Choose a familiar public hostname. The commands below use www.microsoft.com; its response is not guaranteed, and it is not a dedicated diagnostic endpoint. Run each command separately:
ping /4 www.microsoft.com
ping /6 www.microsoft.comMicrosoft documents /4 and /6 as forcing the respective address family for a hostname. Each command normally sends four echo requests and then stops. Press Ctrl + C if you need to stop sooner.
Read the destination shown above the replies. The IPv6 attempt should show a colon-separated address. Replies establish that echo traffic reached that destination and returned at that moment. They do not measure broadband capacity, certify every website or prove that your browser selected the same route.
| Observation | Interpretation and next action |
|---|---|
| Both commands receive replies | Both tested paths worked. If normal applications also work, there is no repair to perform. |
| IPv4 replies; IPv6 times out | IPv6 echo traffic did not return. Repeat with another familiar public hostname before blaming the home connection. |
| IPv6 cannot find the host | The name did not resolve to a usable IPv6 destination in this attempt. That is different from resolving an address and failing to reach it. |
| Both time out, but websites load | Echo requests may be filtered. Keep the result inconclusive; do not turn off a firewall to make ping succeed. |
For a hypothetical result, four replies over IPv4 and zero over IPv6 mean only that this particular comparison differed. The two commands may reach different servers, and remote servers can filter echo requests. Compare the hostname, address family, time and actual application symptom rather than announcing that “the internet is broken.”
When the evidence points back toward home
If several destinations fail over IPv6 while IPv4 works, compare another personally owned device on the same home connection. Repeat the family-specific checks on another Windows 11 PC if one is available. A fresh website load on a phone proves general connectivity, but cannot establish which address family supplied it.
If the PC shows only a link-local IPv6 address, ask the ISP whether your service and router support native IPv6 and whether it should already be provisioned. Do not guess a static address. The IETF home-router requirements distinguish receiving provider address space from distributing configuration to household devices. An ISP-facing address alone does not establish that the household side received usable configuration.
Give support the router model, whether multiple devices are affected, the relevant address categories and the paired command results. Ask them to check provider provisioning, delegated address space and household router advertisements. There is no universal router menu path for these tasks.
These checks need no undo: close Command Prompt when finished. If you previously changed a router setting, restore the exact recorded prior value rather than guessing. Avoid factory resets, registry recipes and disabling IPv6 as exploratory fixes. They change the evidence and can introduce a second problem.
A global address is not a firewall verdict
IPv6 addressing and permission to accept incoming connections are separate matters. Keep the router's IPv6 filtering and the PC's firewall enabled. The IETF router requirements call for security capabilities but explicitly do not establish whether vendors enable them by default. A public-looking address therefore proves neither exposure nor protection.
If browsing and both tested paths work, leave the setup alone. If an application still fails, record that narrower symptom. For name-resolution investigation, continue with the DNS diagnosis guide; an IPv6 label by itself is not a diagnosis.
Sources, versions & scope
The steps describe the documented controls and expected checks; they are not a claim that every device or software release has been physically tested. Platform and version differences are stated with the procedure.
