AV2 powerline kills my connection, do I need QoS to fix this?

[tgl]

Because you were many to reply, so I take it as interested in this issue, I'll report when done.

Yeah, please do.

I may even push testing a bit further by testing both PLA I have, one is AV2 and one is G.hn. From previous testing I know the G.hn was outperforming the AV2 in both download/upload but my son was reporting some issue when gaming so I've decided to put back the AV2 and see if it's better for him. I don't hear from him about issues like before but now it's me who experience issues.

Interesting. FWIW, I had the opposite experience: I found AV2 substantially faster and more stable than G.hn in exactly the same use-case. But I know that that wiring is old and the grounding is probably sub-par, so maybe AV2 can tolerate that better ... and anyway, that's only one data point.

 

[meistadieb]

@Rhialto What kind of internet service are you using? Do you know if this is IP/VDSL based technology? PLAs and IP based are operating in the same frequenz spectrum and could interfere each other (this is also mentioned by fritzbox (popular brand in germany: https://avm.de/service/wissensdaten...de-moglicherweise-durch-Powerline-verursacht/))

 

[drinkingbird]

@Rhialto What kind of internet service are you using? Do you know if this is IP/VDSL based technology? PLAs and IP based are operating in the same frequenz spectrum and could interfere each other (this is also mentioned by fritzbox (popular brand in germany: https://avm.de/service/wissensdaten...de-moglicherweise-durch-Powerline-verursacht/))

If your phone line and power line are interconnected you have bigger problems to deal with.

Everything is IP based. That has nothing to do with it and IP does not have any frequency.

 

[meistadieb]

If your phone line and power line are interconnected you have bigger problems to deal with.

Everything is IP based. That has nothing to do with it and IP does not have any frequency.

In Germany VDSL lines or the technology is often sold as/called "IP" based (https://www.telekom.com/en/glossary#glossar381604) in comparison to the ADSL technology. So sorry for the misunderstanding I have created.

And powerline as well as VDSL are operating in the same frequencies range. Just check https://en.wikipedia.org/wiki/VDSL and g.hn for example https://en.wikipedia.org/wiki/G.hn
And if he is using both technologies they could have impact on each other (speed decrease, disconnects).

From a brand of PLA: https://www.devolo.co.uk/about-devo...tion-between-vdsl-and-powerline-communication

In german they also have a guide how to change settings related to the VDSL profile used: https://www.devolo.de/ratgeber/vdsl-dim

 

[drinkingbird]

In Germany VDSL lines or the technology is often sold as/called "IP" based (https://www.telekom.com/en/glossary#glossar381604) in comparison to the ADSL technology. So sorry for the misunderstanding I have created.

And powerline as well as VDSL are operating in the same frequencies range. Just check https://en.wikipedia.org/wiki/VDSL and g.hn for example https://en.wikipedia.org/wiki/G.hn
And if he is using both technologies they could have impact on each other (speed decrease, disconnects).

From a brand of PLA: https://www.devolo.co.uk/about-devo...tion-between-vdsl-and-powerline-communication

In german they also have a guide how to change settings related to the VDSL profile used: https://www.devolo.de/ratgeber/vdsl-dim

They are running over totally separate wires, doesn't matter if they use the same frequency. Your phone line does not attach to your power line.

All internet access including ADSL and VDSL is IP based.

 

[meistadieb]

They are running over totally separate wires, doesn't matter if they use the same frequency. Your phone line does not attach to your power line.

And? Tone Information does not care... If the wires are next to each other... Just read:

Powerline adapters may cause intermittent connection of DSL modem router in a few rare cases | TP-Link

Follow this article to enable the Lower PLC-to-VDSL Interference mode or cut the phone line short and straighten it to avoid intermittent connection of DSL modem router caused by powerline adapters.

www.tp-link.com

https://assia-inc.com/wp-content/uploads/2015/03/ISPLC2015-Impact.pdf

 

[Tech9]

@Rhialto had the same issue in mid 2021 and seems like it was never resolved. Resolving an issue requires some user actions beyond just asking questions. A year and a half time is plenty to experiment with all possible QoS options and settings at least. I hope in next year and a half we get results from Ethernet or Wi-Fi to the son's computer eliminating the PLAs. So @drinkingbird and @meistadieb - no rush.

Problems with gaming whilst another user is downloading a large file

Hi wonder if anyone can help. I have a MoCA setup in my house. Everything normally works fine. I have the cable modem connected to a router which is brand new. I have then connected from the router to the Motorola MoCA box. Then into the coax. Then in my study out of the coax into another...

www.snbforums.com

 

[Rhialto]

@Rhialto had the same issue in mid 2021 and seems like it was never resolved.

Yes, it is so sporadic that I just mostly ignored until I got impacted in a multiplayer game with a team and suddenly saw red warning icons all over the screen and ping reached 600-800ms instead of usual 40ms I'm used to. It was not my thread, just my input in someone else thread with a similar situation. I never knew if QoS would be a solution as I never asked in the Asus forum like suggested, it's only now that I'm asking.

Since you were looking at it, have you also found this thread of mine? I tested 4 PLA and the date tells me that I was using the AV2 at that time because later I was able to get my hands on G.hn devices and I think the issue went away but like I said it's my sons who had disconnection issues so justy recently I reverted back to the AV2 and there we are.

No rush, exactly. While the solution will prolly be to go mesh, I find interesting many of you joined the discussion. I should be able to test around the 17th.

What kind of internet service are you using?

Cable 400/50.

 

[drinkingbird]

And? Tone Information does not care... If the wires are next to each other... Just read:

Powerline adapters may cause intermittent connection of DSL modem router in a few rare cases | TP-Link

Follow this article to enable the Lower PLC-to-VDSL Interference mode or cut the phone line short and straighten it to avoid intermittent connection of DSL modem router caused by powerline adapters.

www.tp-link.com

https://assia-inc.com/wp-content/uploads/2015/03/ISPLC2015-Impact.pdf

If the wires are next to each other over a significant distance the EMI interference is going to be much more of a problem than any potential high frequency bleed. Likely the DSL is going to be working lousy in that case even without PLA in use.

Regardless, I don't think the OP has DSL anyway.

 

[sfx2000]

In Germany VDSL lines or the technology is often sold as/called "IP" based (https://www.telekom.com/en/glossary#glossar381604) in comparison to the ADSL technology. So sorry for the misunderstanding I have created.

And powerline as well as VDSL are operating in the same frequencies range. Just check https://en.wikipedia.org/wiki/VDSL and g.hn for example https://en.wikipedia.org/wiki/G.hn
And if he is using both technologies they could have impact on each other (speed decrease, disconnects).

That is a good point to consider... one I hadn't considered actually...

PLA's can be very noisy and interfere in some cases - depends on the VSDL profile used - some of the PLA's have selective notch filters, both for G.Hn and HPAV, that can help - depends on the vendor of the PLA

If the modem is VDSL, there may be debug pages that can show error counters - test with and without the PLA, and see if that changes things

 

[Rhialto]

Ok some quick tests, this is the setup:

Have him download a game on Steam and when I ping my router gateway I get this with the AV2:

Stop download/restart download and got this:

Strange enough, when I plug the G.hn instead my PC is not impacted, I get 1ms or less BUT his PC have lots of delay whatever the adapters used.

From what I understand there must be a lot of collisions/retry between the 2 adapters talking to each other but why the AV2 impact my wired connection and the G.hn does not?

 

[drinkingbird]

Ok some quick tests, this is the setup:

View attachment 48942



Have him download a game on Steam and when I ping my router gateway I get this with the AV2:

View attachment 48940

Stop download/restart download and got this:

View attachment 48941

Strange enough, when I plug the G.hn instead my PC is not impacted, I get 1ms or less BUT his PC have lots of delay whatever the adapters used.

From what I understand there must be a lot of collisions/retry between the 2 adapters talking to each other but why the AV2 impact my wired connection and the G.hn does not?

You need to test what happens with no PLAs at all. Bring his PC into another room if needed. As for the difference between the two PLAs, could be any number of things, maybe one is only coming up at 100 meg, maybe one is dropping so bad on his end that it never stresses the router buffers, etc.

Essentially his PC is acting like a wireless client with really bad signal, degrading the whole wireless network. In this case it is wired, but same idea.

 

[tgl]

When you say "router gateway", which machine are you pinging exactly? The AC1900? The broadband modem? Something at your ISP?

It's hard to see how the PLAs could affect pings between your PC and the AC1900. However, if you're pinging something upstream of that then the returning ping packet would contend for wire time with the download data. So it might be that this is basically a QoS issue and the download data is being prioritized ahead of the ping. (If that's true, then the PLAs are performing just fine --- because if they were introducing any delay then there would be plenty of opportunities for the ping packet to slip through.)

I agree with @drinkingbird that the only way to be entirely sure if the PLAs are at fault is to try the same experiment with your son's PC connected to the router by a regular ethernet cable.

 

[drinkingbird]

When you say "router gateway", which machine are you pinging exactly? The AC1900? The broadband modem? Something at your ISP?

It's hard to see how the PLAs could affect pings between your PC and the AC1900. However, if you're pinging something upstream of that then the returning ping packet would contend for wire time with the download data. So it might be that this is basically a QoS issue and the download data is being prioritized ahead of the ping. (If that's true, then the PLAs are performing just fine --- because if they were introducing any delay then there would be plenty of opportunities for the ping packet to slip through.)

I agree with @drinkingbird that the only way to be entirely sure if the PLAs are at fault is to try the same experiment with your son's PC connected to the router by a regular ethernet cable.

The PLA can actually have a big impact on other wired LAN devices. Just like on the WAN, if you have a 1G interface that can only transmit a fraction of that, buffers will fill up and on these cheaper switches, everyone shares the buffer. Essentially the same thing that causes buffer bloat on WAN is in play here. Add on top of that the stress of buffering and dropping all the packets, all the retransmissions compounding the issue, etc. Just a lot for an essentially software based router/switch to handle.

If they forced the port to the PLA to come up at 100M/Full or even 10M/Full it would probably help both systems quite a bit, but a better option is likely going to be MOCA or even wireless.

Of course if you give him a gig link for testing that is probably just going to move the issue to the WAN port, but at least you can confirm then that it is the PLA, get that resolved, then work with QOS and/or limiting his physical link speed to address that.

 

[Rhialto]

When you say "router gateway", which machine are you pinging exactly? The AC1900?

Yes, 192.168.x.1 and while he was downloading, it was far from max speed we have seen before so just saying that the PLA bandwidth was not maxed out so it was able to breath.

I agree with @drinkingbird that the only way to be entirely sure if the PLAs are at fault is to try the same experiment with your son's PC connected to the router by a regular ethernet cable.

I would need a 80-100 feet cable or need to move his PC in basement where I am and also the router is. Not something I'm willing to do now.

Maybe I will try to get rid of those 2 PLA and buy this MOCA instead which offer Wifi. One son could be wired and the other could be on the Wifi this MOCA offer. I would need to make sure the frequencies used have no impact on what's already in the cable. I've seen a diagram on their website showing less TV channels after the MOCA so I'm a bit worried as I don't know all the frequencies being used currently.

 

[drinkingbird]

Yes, 192.168.x.1 and while he was downloading, it was far from max speed we have seen before so just saying that the PLA bandwidth was not maxed out so it was able to breath.

No, that's not how it works, if it is erroring and not reaching max speed, the bandwidth IS maxed out. Just because it says it CAN do a gig or multiple gigs, doesn't mean it is able to. PLAs are very prone to interference and terrible quality connections and that (as you've experienced) can cause a cascade effect on the rest of the network. If your fridge is running, it may be slower, if it is warm out, it may be faster. It is very unreliable and unpredictable, except in houses with new wiring where the PLAs are on the same segment (even then, they'll have some errors).

Maybe I will try to get rid of those 2 PLA and buy this MOCA instead which offer Wifi. One son could be wired and the other could be on the Wifi this MOCA offer.

MOCA will likely be far better than PLA, depending on your coax wiring and splitters.

Also note that a 100' patch cord can be gotten pretty cheap on Amazon and elsewhere, not a terrible thing to have around for testing or temporary use anyway.

 

[tgl]

Also note that a 100' patch cord can be gotten pretty cheap on Amazon and elsewhere, not a terrible thing to have around for testing or temporary use anyway.

I was about to say the same thing --- it'd be better to have a spare 100' cable than to spend more than that on gear that doesn't fix your problem. (I'd lend you mine if we were neighbors ... maybe you have a friend who could lend you one?)

Now, if you do have a good coax setup in place, MOCA could be a great answer. But I'm not entirely convinced yet that the problem is the PLAs and not somewhere upstream.