Re: Slow Gigabit Fios Internet
dexman
Community Leader
Community Leader

Cang_Household might be on to something. Would it be possible to check to see if you're now on IPv6? 🤔

Re: Slow Gigabit Fios Internet
maestro2
Contributor - Level 1

I believe both IPv4 and IPv6 are enabled on Verizon router by default, but I can disable IPv6 on my computer and then test the connection.

I will double check the IP version on the router as well.

0 Likes
Re: Slow Gigabit Fios Internet
maestro2
Contributor - Level 1

Disabling WiFi did not do much: the Verizon speedtest would randomly complete or fail and fast.com was showing weird results for upload speed.

As expected both IPv4 and IPv6 were enabled on the router and my test computer, but my computer public IP on Verizon speedtest page and other sites was showing IPv4 address.

Disabling IPv6 on Verizon router seemed to change a lot: the Verizon speedtest would go smoothly and fast.com showed expected results.

Any ideas what is going on?

Re: Slow Gigabit Fios Internet
dexman
Community Leader
Community Leader

Cang_Household found that Intel-based NICs have issues with IPv6. Intel has been aware of the situation for a while but has not been able to rectify the situation. By disabling 6 and seeing expected test results, it would indicate that there is an Intel NIC present.

Re: Slow Gigabit Fios Internet
maestro2
Contributor - Level 1

In that case I can re-enable IPv6 on Verizon router, and disable IPv6 of computer's Intel NIC? 

0 Likes
Re: Slow Gigabit Fios Internet
dexman
Community Leader
Community Leader

I will defer to Cang_Household for an answer. He is more familiar with this trouble than me.

Re: Slow Gigabit Fios Internet
maestro2
Contributor - Level 1

It looks like a multi-million dollar corporation left thousands of paying customers with Intel NICs on community support...

Sad and funny at the same time.

0 Likes
Re: Slow Gigabit Fios Internet
Cang_Household
Community Leader
Community Leader

@maestro wrote:

It looks like a multi-million dollar corporation left thousands of paying customers with Intel NICs on community support...


Well, this also shows communities like this Forum is useful. My thought is that companies should put those who actually build the hardware and software in the community for a day or two periodically, so they can know what needs to be fixed and what the customers actually want, instead of being solely guided by the product/sales/marketing teams.

Dexman, sorry I was away and taking a break from work/computer. I can now answer the question about IPv6 to the OP: you can 1) disable IPv6 at router level, 2) disable IPv6 at NIC level, 3) disable IPv6 TCP Checksum Offload (this is the root problem and suggested by Intel in the technical advisory). Disabling IPv6 would not serve you good because the entire point of the recent IPv6 rollout was to allowing customers to use IPv6 to access the part of the Internet that was previously not accessible via IPv4. Disabling the TCP checksum offload would virtually solve the problem and still allow you to use IPv6.

Re: Slow Gigabit Fios Internet
maestro2
Contributor - Level 1

Thank you for details.

Based on information you provided I found this article that applies to my Intel NIC, but I have not had a chance to try this yet:

https://www.intel.com/content/www/us/en/download/19174/disabling-tcp-ipv6-checksum-offload-capabilit...