Why would a cable allow IPv4 but interfere with IPv6 connectivity?

[Puffnstuff]

Folks I've never encountered an issue like this before which is why I ask this question. I've had some issues lately with IPv6 connectivity and my router. My IPv4 connection has never had any such issues, however, I considered my cable modem and the connecting cable and decided to swap out the cable in an effort to rule out possible causes. Once I removed the old cable and replaced it with a cat 6 cable my IPv6 connection was retained by my router.

This is where I'm confused because if the cable was bad wouldn't it also interfere with the ability to maintain the IPv4 connection? Nothing else was changed except for the cable yet my router is able to keep and renew its IPv6 lease without incident.

 

[bill001g]

The cable can not directly cause that problem. It is really stupid it only understand electrical levels. It has no concept of data concept like IP Packets and the type of addresses being used. It pretty much only knows if a bit is zero or one but even that is not 100% true.

IPv6 does all kinds of strange things. You would think after 20yrs of everyone screaming ipv6 is the future it would work better. Unless your ISP provides you with IPv6 support I would disable it. It just causes problems. Even where it is supported many times your traffic will be slower because there are fewer ISP interconnects that support IPV6. If you live in asia it "might" be ok to use it but so far it is very rare to get any advantage using ipv6

 

[Puffnstuff]

I know how unlikely it seems that the cable was the issue but the empirical evidence says otherwise. I'm wondering if the resistance level was too high in the old cable but the new one works for sure.

 

[Paul NZ]

Got that right. I think my ISP supports IPv6 because if it's enabled it shows internet under the network adapter

However if it is enabled for one reason or another it started to conflict with the ipv6 ip address on the other computer ( Win7).

This is Win10

I have no idea why it would , so I disabled it

 

[Puffnstuff]

Got that right. I think my ISP supports IPv6 because if it's enabled it shows internet under the network adapter

However if it is enabled for one reason or another it started to conflict with the ipv6 ip address on the other computer ( Win7).

This is Win10

I have no idea why it would , so I disabled it

Sounds like the DHCP function on the router is not working correctly if clients are getting conflicting addresses. What router are you using and does it have the latest firmware?

 

[nigelivey]

I know how unlikely it seems that the cable was the issue but the empirical evidence says otherwise. I'm wondering if the resistance level was too high in the old cable but the new one works for sure.

" empirical evidence says otherwise" only if you decide to rule out coincidence. Resistance levels plays no part in this.

 

[Paul NZ]

Got that right. I think my ISP supports IPv6 because if it's enabled it shows internet under the network adapter

However if it is enabled for one reason or another it started to conflict with the ipv6 ip address on the other computer ( Win7).

This is Win10

I have no idea why it would , so I disabled it

Sounds like the DHCP function on the router is not working correctly if clients are getting conflicting addresses. What router are you using and does it have the latest firmware?

Its a crap ISP modem that they gave when I changed to Fibre. I was thinking the same thing, its screwed lol

But since I cant afford to buy another yet (I'll have to get one that the phone plugs into) since I'm not using the phone jack for the phone. It's a useless Huawei HG659. And yup the latest fw is on it.It was on it when I changed to Fibre