Powerline at fault?


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A weird issue's arisen in our house. Around a fortnight ago, my brother started getting annoying lag spikes any time he was gaming online, regardless of the game (usually, it's Smite or FIFA 15). Everything else has been fine. After a few calls to BT - and a few line resets - we know the problem is on our end, but we don't have a definitive idea what could be causing it; we've effectively narrowed it down to either our powerline adapters (the most likely culprit at the moment), my PC, or the house's electrical wiring.  :s

 

Both my brother and I use our PCs upstairs, connected wired through powerline adapters - these ones, to be precise, as well as a TRENDnet one that's feeding the internet from the BT Home Hub 4 downstairs and upstairs through the electrical wiring to us. When both of our PCs are on, he has problems playing online, but when mine's off, he has no problems whatsoever (tested it again earlier just turning off my powerline adapter and again, it was perfect for him). As far as I know, there's nothing on either PC that could be causing any problems - uTorrent and Steam usually hog the internet in the background on my PC, but the problems persisted even with them closed - and we haven't made any changes to our network recently; hell, we've been using those powerline adapters since June 2013, so it's weird that it's going wrong now.

 

The reason why I mention the house's electrical wiring as a potential culprit is because there has been a conservatory built in recent weeks - with electrical wiring out there, too - and the problems didn't begin until that was done.

 

Has anyone here experienced this before or know anything I can do here to try and pinpoint the problem? Because at the moment, I don't know what to do; solutions running through my mind are to either get new powerline adapters, get a long ethernet cable and run it upstairs, or get an engineer out to relocate the modem and Home Hub upstairs. :pinch:

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try connecting the pc directly into the router/modem

 

if it works, its the powerline/eletric grid

 

there are several solutions: ethernet cables, wireless...

 

perhaps router config can change this too.. i once had a problem playing Counter Strike in lan with a friend at his house, 2 pcs in lan, the server creator could play fine but the client player couldnt. A factory reset in the router fixed as far as I remember

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Powerline adapters communicate over the grid frequency.

With many power supply units and wall-warts being switching devices and less and less transformer based, the grid frequency gets polluted with harmonic distortions. Basically making the communication over the grid frequency more difficult.

You mentioned that the issue started a forth night ago, are there any new appliances that have been bought or plugged into new or different wall sockets? Have you tried a different socket?

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try connecting the pc directly into the router/modem

 

if it works, its the powerline/eletric grid

 

there are several solutions: ethernet cables, wireless...

 

perhaps router config can change this too.. i once had a problem playing Counter Strike in lan with a friend at his house, 2 pcs in lan, the server creator could play fine but the client player couldnt. A factory reset in the router fixed as far as I remember

I always forget something when I make a tech support post here. :pinch:

 

Didn't use one of the PCs, but we did directly connect one of the downstairs laptops - which is normally on wi-fi - to the Home Hub and ran a speed test as per the instructions from BT. We're getting ~50Mb download tops upstairs on the powerline - ~40Mb if both of us are on - and we got 72Mb earlier through a direct connection, which is pretty much the speed we're paying for (up to 76Mb).

 

Router config can be ruled out here, too, as the last time we called BT, they got us to factory reset the Home Hub; it's still on default settings at the moment, besides the SSID and the admin & wi-fi passwords.

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Powerline adapters communicate over the grid frequency.

With many power supply units and wall-warts being switching devices and less and less transformer based, the grid frequency gets polluted with harmonic distortions. Basically making the communication over the grid frequency more difficult.

You mentioned that the issue started a forth night ago, are there any new appliances that have been bought or plugged into new or different wall sockets? Have you tried a different socket?

Dishwasher and another TV, but they didn't get plugged in until after the problem started. Just remembered an electric garage door's been installed, too, but again, after the problem started.

I'll try a different socket with mine later, but that isn't an option for my brother; he's only got a single pair of main sockets in his room.

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Powerline adapters communicate over the grid frequency.

With many power supply units and wall-warts being switching devices and less and less transformer based, the grid frequency gets polluted with harmonic distortions. Basically making the communication over the grid frequency more difficult.

You mentioned that the issue started a forth night ago, are there any new appliances that have been bought or plugged into new or different wall sockets? Have you tried a different socket?

 

this.

i used powerline adapters a few years ago without problem, then suddenly the connection was seriously bad. i ran some tracerts and discovered many dropped packets and lag on the network. i eventually narrowed it down to a cheap psu i'd put into my home server as it had recently failed. having this on the mains network screwed everything. switched it off, everything fine. as a result i've recently hardwired cat6 all over the house i'm renovating to avoid future issues with powerline adapters.

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I always forget something when I make a tech support post here. :pinch:

 

Didn't use one of the PCs, but we did directly connect one of the downstairs laptops - which is normally on wi-fi - to the Home Hub and ran a speed test as per the instructions from BT. We're getting ~50Mb download tops upstairs on the powerline - ~40Mb if both of us are on - and we got 72Mb earlier through a direct connection, which is pretty much the speed we're paying for (up to 76Mb).

 

Router config can be ruled out here, too, as the last time we called BT, they got us to factory reset the Home Hub; it's still on default settings at the moment, besides the SSID and the admin & wi-fi passwords.

 

Doing a speed test isn't going to help you find the cause of lag spikes.

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Powerline adapters communicate over the grid frequency.

With many power supply units and wall-warts being switching devices and less and less transformer based, the grid frequency gets polluted with harmonic distortions. Basically making the communication over the grid frequency more difficult.

You mentioned that the issue started a forth night ago, are there any new appliances that have been bought or plugged into new or different wall sockets? Have you tried a different socket?

 

You could be right, but for the wrong reasons.

 

Power line adapters do not communicate over the "grid frequency". That's 50/60Hz. The adapters communicate in the MHz range.

Harmonic distortions are typically up to 2kHz, again, nothing to do with the communication in the MHz range and can have no affect here.

However, it is possible for the PSU of the various devices plugged into the electrical system in the house to affect the speeds of these PLAs due to emissions conducted from them into the electrical network.

 

So, it could be due to a new appliance plugged in, but it is not related to harmonics or grid frequency.

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Doing a speed test isn't going to help you find the cause of lag spikes.

It did show up spikes in the download speed sometimes. Forgot to mention Pingtest, too; got quite a few dropped packet results.
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this.

i used powerline adapters a few years ago without problem, then suddenly the connection was seriously bad. i ran some tracerts and discovered many dropped packets and lag on the network. i eventually narrowed it down to a cheap psu i'd put into my home server as it had recently failed. having this on the mains network screwed everything. switched it off, everything fine. as a result i've recently hardwired cat6 all over the house i'm renovating to avoid future issues with powerline adapters.

It looks like the problem's along the same lines as yours, although in this case, it seems to be my PC. The powerline adapter runs fine with everything else connected, but as soon as the ethernet cable from my PC is plugged in, the lag rears its ugly head again; same situation with the adapter plugged into a different socket at the other end of the room and using a different ethernet cable. :pinch: So it sounds like my power supply's causing the trouble; even more annoying considering this one's an RMA replacement from a year-and-a-half ago.

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"but as soon as the ethernet cable from my PC is plugged"

That points more to your PC putting out a lot of noise on the network.. Be it faulty nic, infection? Run a wireshark and see what your nic is putting on the wire.

If it was your PC power supply, you would think just plugging it power and turning it on would cause the problem. Since you say its when you connect the network connection, that points to flooding the network with something that is saturating the powerline connection, which could cause lag in network performance.

A wireshark trace should show if its flooding the network with garbage or real traffic. Don't be doing anything like download files, etc. when you do the sniff and your trace should be fairly quiet

if your flooding the network with traffic and your not really doing anything, then something is up. If you have questions on anything you might see in the sniff or need help setting up wireshark just PM or post.

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A wireshark trace should show if its flooding the network with garbage or real traffic. Don't be doing anything like download files, etc. when you do the sniff and your trace should be fairly quiet

if your flooding the network with traffic and your not really doing anything, then something is up. If you have questions on anything you might see in the sniff or need help setting up wireshark just PM or post.

OK, I've had it running for ~10 minutes now, and it's come up with 30 errors, which I can't make heads nor tails of...

 

post-151617-0-20646300-1426280036.png

 

EDIT: 36 now; all six new ones in the first group.

 

The bottom two groups only came up when I started browsing.

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i agree with the above. my problems were related to the mains being "infected" when the psu was on the mains network. it seems slightly different in your case. you could try a usb network adapter and see if that produces the same result, they are quite cheap?

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Retrans are to be expected, depending on what you are doing.  Retransmissions are common, now if your seeing too many then something is wrong sure.

 

If you show me the actual sniff I can tell you what those errors are.  Did you save it, could you email it to me..  PM me and I will send you my email account, etc.

 

I would be more interested in general traffic that is being put on the wire - what are you doing?  You really should not be seeing that many packets if your computer is not moving files around, surfing the net, etc. Do you have a lot of broadcast traffic, etc.  Really need to see the sniff to see what might be going on with the network.  Is your machine flooding the network with broadcast, etc.

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Retrans are to be expected, depending on what you are doing.  Retransmissions are common, now if your seeing too many then something is wrong sure.

 

If you show me the actual sniff I can tell you what those errors are.  Did you save it, could you email it to me..  PM me and I will send you my email account, etc.

 

I would be more interested in general traffic that is being put on the wire - what are you doing?  You really should not be seeing that many packets if your computer is not moving files around, surfing the net, etc. Do you have a lot of broadcast traffic, etc.  Really need to see the sniff to see what might be going on with the network.  Is your machine flooding the network with broadcast, etc.

I did save it from last night; I'll upload it and PM you the link.

 

...aaaand sent.

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You have plexserver running?  Seems to be putting out quite a bit of traffic over udp to 32412 and 32414

 

post-14624-0-80232800-1426349979.png

 

Still looking into this traffic - I don't really see anything that should take your network down.. But some odd stuff and noisy for you not doing anything ;)

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You have plexserver running?  Seems to be putting out quite a bit of traffic over udp to 32412 and 32414

If it's this, I uninstalled that a while ago. Maybe it didn't uninstall properly?

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This is also weird traffic

 

So your dns server at 192.168.1.254 is answering you for dns queries, but your box at 1.70 is sending back that port is not open.  Strange..  Are you running some 3rd party firewall on this box 1.79

 

I will have to follow the time stamps.. But its odd..

 

post-14624-0-51484100-1426350740.png

 

edit:  So for example here you ask for www.facebook.com twice, you get an answer, and then the 2nd answer since you asked twice.  Your box sends back hey that port is closed.

 

Very odd

 

post-14624-0-01436500-1426350955.png

 

Not sure why you would ask twice..  Do you have your dns 192.168.1.254 listed twice?

 

edit: ok noticed this in the 2nd trace you sent.  Saw in first as well.. Your box at .89 really wants to know where .91 is - but seems he must be off or doesn't exist, cause no answer to this arp

 

post-14624-0-34900200-1426351342.png

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So your dns server at 192.168.1.254 is answering you for dns queries, but your box at 1.70 is sending back that port is not open.  Strange..  Are you running some 3rd party firewall on this box 1.79

 

edit: ok noticed this in the 2nd trace you sent.  Saw in first as well.. Your box at .89 really wants to know where .91 is - but seems he must be off or doesn't exist, cause no answer to this arp

1.70 is my PC at the moment. I've tried to find the 1.79 device, but :iiam:  Here's how it comes up in the Home Hub...

post-151617-0-38548000-1426351740.png

 

There's four Android devices running in the house: my Nexus 5, my dad's Moto G, his Nexus 7, and some TV box thing that he bought off eBay recently, but neither of those have the MAC address listed on there. Is there a chance someone's snuck in on the network?

 

1.89 is my brother's PC, and there's absolutely nothing on the network here on 1.91.

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OK, today, my Nexus 5 took the elusive 1.79 address on the network - everything's now labeled on the network, by the way; no unknown devices - and through a bit more trial and error, it seems that is the actual source of the problem; perfectly fine when the wi-fi's off, but when it's on and connected to the home network, hello, lag spikes.  :s I don't know if there's an Android equivalent to Wireshark, so I'll happily welcome app suggestions there; meanwhile, I'll grab a decent free antivirus app and see if it turns up anything.

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What are you running as your router or switches. Its possible to sniff all the traffic on your network. Your machine will only see broadcast traffic. Your router would see all broadcast traffic and anything headed outbound. IF you want to watch all inter client talk you would need to do a span port on your switch, etc. Do you have a smart/managed switch?

One thing I will say from the 2 sample sniffs you sent is there quite a bit of noise, nothing that should really kill a network. But could really hinder wifi if going out on the wifi. Wifi is shared, noise can kill what bandwidth that others could be using for legit traffic, etc.

One thing you can do is isolate your wifi segment from your wired segment, depending on your AP/Wifi router is you can disable broadcast traffic, you could do igmp snooping on switch to help remove unwanted multicast/broadcast from using up wifi bandwidth, etc.

I would make sure you disable all your ipv6 on all devices you can, or spend the time to actually set it up if you want to use it. Make sure if your running plex that its setup correctly and not drowning your network with broadcast. The thing that I also found weird was all the udp traffic you had going to outside IPs form your .70 box when you were not really doing anything you said, etc..

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Kaspersky Internet Security and Avast Mobile Security both turned up nothing, but I think I've fixed it now; I went in the security settings and cleared all the stored credentials from my phone (one of which recently forced me to have a secure screen lock of some kind; the None and Swipe options were greyed out), and it's all been playing fine online since for a couple of hours, now.

 

Thanks for all of your help, everyone; especially BudMan for sifting through the traffic. :) Sorry it didn't turn out to be that at fault. Never encountered such a weird issue before.

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What are you running as your router or switches. Its possible to sniff all the traffic on your network. Your machine will only see broadcast traffic. Your router would see all broadcast traffic and anything headed outbound. IF you want to watch all inter client talk you would need to do a span port on your switch, etc. Do you have a smart/managed switch?

One thing I will say from the 2 sample sniffs you sent is there quite a bit of noise, nothing that should really kill a network. But could really hinder wifi if going out on the wifi. Wifi is shared, noise can kill what bandwidth that others could be using for legit traffic, etc.

One thing you can do is isolate your wifi segment from your wired segment, depending on your AP/Wifi router is you can disable broadcast traffic, you could do igmp snooping on switch to help remove unwanted multicast/broadcast from using up wifi bandwidth, etc.

I would make sure you disable all your ipv6 on all devices you can, or spend the time to actually set it up if you want to use it. Make sure if your running plex that its setup correctly and not drowning your network with broadcast. The thing that I also found weird was all the udp traffic you had going to outside IPs form your .70 box when you were not really doing anything you said, etc..

It's a BT Home Hub 4; standard issue device for anyone on BT Infinity and it's fairly locked down compared to previous routers I've used before (the D-Link DIR-615 that Virgin Media gave us before was even worse, mind; ended up buying a Netgear WNR3500Lv2 to use instead). No switches on the network, either; all that's running is the BT modem, the Home Hub, the powerline adapters and a Netgear WN3000RP range extender.

 

My PC's thankfully wired through the powerline adapters. Wi-fi's been good so far for everyone; had this setup for nearly two years.

 

I'll make sure to disable IPv6 on all the other computers later on; I did look it up earlier on, and it seems BT still doesn't support it for residential customers. There were murmurs of them implementing it back in 2013 after trialing Carrier Grade NAT, but haven't heard anything since that besides for business customers. Seeing this in the Home Hub settings though...

 

post-151617-0-69452000-1426463609.png

 

...they probably aren't in a hurry to implement it.

 

Found out earlier Plex was still on my dad's laptop, too, so I uninstalled it to be on the safe side (only used it for Chromecasting local videos, which Videostream does just as well).

 

 

Thanks again for your help!

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