How can two home networks interfere with one another?

StewartR said:
Good suggestion. However I cannot see any of his devices on our network at present. It is an intermittent problem. Unplugging things and seeing what has happened is not an efficient means of solving it - albeit it might be the only means if we can't come up with anything better.
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Probably quicker than the 2 1/2 hours since you started the thread, Stewart! My first thought would be to find out what the "Unknown" device is and blocking it if it's a complete mystery.
 
DemiLion said:
Did you read what I wrote above?

That's exactly what was happening in my network. Next door was BT and I'm Virgin.

I suspect that the two routers formed there own wireless connection with my router acting as a relay for the BT one.

Once again, the fix is:

Change your DHCP IP range from the default one and change your WiFi channel from auto to a fixed one, preferably at least 2 to 3 channels away from your neighbours.

And yes, we had hard wired, PoE adapters and wireless running.
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Yes, I did read it. But when you said you never bothered to look for a reason, I kind of tuned out.

Anyway ... If that might be what's happening to me, then your solution might work. I have no idea how to change the IP address range or the wifi channel, but I guess I can find out...
 
I have to go back to the office now so I'll be offline for a few hours. Thanks for all the help so far. If anybody else has any views on DemiLion's suggested fix, please post them. When I get back that's what I'll try unless somebody has a better idea.
 
Ok..so where are the Powerlines in that device list? There should be at least two and they should show up on the DHCP list.
 
StewartR said:
Yes, I did read it. But when you said you never bothered to look for a reason, I kind of tuned out.

Anyway ... If that might be what's happening to me, then your solution might work. I have no idea how to change the IP address range or the wifi channel, but I guess I can find out...
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I spent 12 years in IT. Sometimes it's better just to find the fix rather than faffing about with the exact reasons.

There's an interface panel on your router (probably under advanced) that will allow you to change the WiFi network channel very easily.

Your default DHCP range will be something like 192.168.0.1 - 192.168.0.255 : 255.255.255.0
Change the third number set, so that it reads along the lines of 192.168.30.1- 192.168.30.255 : 255.255.255.0

ONLY change the third number block.
 
Do not rely on just changing the DHCP!

Changing the DHCP range is akin to leaving a burglar in your house and changing the locks but they are already inside. It's your security of your home network, you wouldn't leave your door unlock and open to see inside so don't do it on a computer network.

Turn off the router for a start to hopefully flush all the cached entries and power off all your devices, everything. Power up the router then one at a time (starting with a device to access the router) turn your individual devices back on, refresh the router to see what its found. Do this one at at time, power up, check router if it found that one device or more. Using FING from your mobile and Softperfect Netscanner from a PC to then probe the network and ensure only that device is added after each device is powered on to confirm what the router is saying. Do this each time. Repeated until you've added all your devices and found the problem that is causing the network sharing. Then report back.
 
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You know, surprisingly I changed all of my passwords, including the WiFi code, but the routers still paired.

Changing the WiFi channel stopped that and changing the DHCP range ensured that there'd be no conflict.
 
DemiLion said:
You know, surprisingly I changed all of my passwords, including the WiFi code, but the routers still paired.

Changing the WiFi channel stopped that and changing the DHCP range ensured that there'd be no conflict.
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The solution was to change the router then not the sticking plaster look the other way fix you implemented.
 
DemiLion said:
I spent 12 years in IT. Sometimes it's better just to find the fix rather than faffing about with the exact reasons.

There's an interface panel on your router (probably under advanced) that will allow you to change the WiFi network channel very easily.

Your default DHCP range will be something like 192.168.0.1 - 192.168.0.255 : 255.255.255.0
Change the third number set, so that it reads along the lines of 192.168.30.1- 192.168.30.255 : 255.255.255.0

ONLY change the third number block.
Click to expand...

If the networks are bridged by some as yet unknown device, there is no guarantee that the neighbour's devices won't get their DHCP requests responded to by Stewart's DHCP server. Been there, scratched my head at that one in the past.
 
Use FING to see what is currently active on your network. You should see a Refresh button so you can refresh it every so often. The numbers that you see like 14-cc-eb-ef-65 etc are a Mac address and will be unique to each device. You will probably be able to match these up with those shown in your router and you can rename each device in FING. This will at least help you figure out what each device is.
Alastair said:
Ok..so where are the Powerlines in that device list? There should be at least two and they should show up on the DHCP list.
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I have 4 powerline adapters around the house and none of them show up in any list of devices in either my router or in FING.
 
onomatopoeia said:
If the networks are bridged by some as yet unknown device, there is no guarantee that the neighbour's devices won't get their DHCP requests responded to by Stewart's DHCP server. Been there, scratched my head at that one in the past.
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Yep, hence the most important point being to change the channel so that they don't bridge.

I spent over a week chasing the cause and in the end opted for a working fix.
 
Just read through this, very strange indeed. I would think that this is likely to be power line adapters as your router configured suggests the devices are Ethernet connected - is your house attached to your neighbour - eg sharing an electrical supply? Supposedly power line adapters are "secure" until the meter?

Also the loxone server might be worth investigating further?

Another option, although a bit of a sticking plaster would be to filter by MAC address, so only allow devices you allow onto your network, although I'm not sure of the functionality of the plusnet (?) router.
 
ecoleman said:
I have 4 powerline adapters around the house and none of them show up in any list of devices in either my router or in FING.
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I briefly had two, but they didn't like the ancient wiring in the house, and they both showed up when plugged in.

Identifying all active devices is the way forward.

It would also be interesting to see one of the mobile devices that's connected (iPhone,Surface Pro, etc.) from next door and see what that shows as the connection.
 
Without sharing the same Service set identifier, being on the same channel will only degrade performance, not bridge networks. As @terrific says there are not many options. You are only seeing devices with ethernet addresses / IP leases on your router. These are not found on simple power line adapters (which is why they don't show up for everyone using them). I wonder if you neighbours wifi is insecure... and its either something like your home automation connecting to it, or has been said plenty of times before (and there are lots of report in google - you share powerline). I would check your powerline adapters and see how to setup / use encryption if you can. I suspect that as powerlines run off a shared medium, it will be shared bandwidth, so when you use it, it could easily affect your neighbours traffic.
 
admirable said:
1. Are you sure he doesn't use powerline adapters? Would he know what they are?
2. Do you know how his smart TV is connected to the internet wired/wireless?
3. Could his Router be a AdHoc connection from your wireless device/router?
4. Do you have an older house that would share a ring main or earth with next door?
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1. Not 100% sure, but I described mine and he said he'd never heard of anything like that. I may have to double-check.
2. Wired definitely - he said there's a cable connecting it to the router. He said he thinks it has wireless capability but they don't use it.
3. Dunno. That's the $64 question.
4. No. They were both built in 1968 and mine has just been rewired.
 
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DemiLion said:
There's an interface panel on your router (probably under advanced) that will allow you to change the WiFi network channel very easily.

Your default DHCP range will be something like 192.168.0.1 - 192.168.0.255 : 255.255.255.0
Change the third number set, so that it reads along the lines of 192.168.30.1- 192.168.30.255 : 255.255.255.0

ONLY change the third number block.
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If only.....

The user manual for my router is here: http://help.demon.net/files/2013/03/TG582n-User-Guide.pdf
Pages ... 94
References to DHCP ... zero

I can change the WiFi network channel if necessary, but not the DHCP range, it seems...
 
I would rule out the power line adapters as the electricity supply underground is 3 phase so only every third house is on the same phase. Your neighbour should be on a different phase.
 
petersmart said:
What OSs are you both running?
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I'm sorry, but I don't see how that's relevant. The list of my devices which my neighbour could see in Windows Explorer included a router, a Windows PC, a Sonos music player, an Amazon Fire TV stick, an Epson printer, a Loxone home automation server, and a TV set top box. I'm not sure that all of them even run OSs.
 
ecoleman said:
Use FING to see what is currently active on your network. You should see a Refresh button so you can refresh it every so often. The numbers that you see like 14-cc-eb-ef-65 etc are a Mac address and will be unique to each device. You will probably be able to match these up with those shown in your router and you can rename each device in FING. This will at least help you figure out what each device is.
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That sounds like it's worth doing. I might also ask my neighbour to allow me to FING his network, and make a list of his MAC addresses.
 
For the devices that don't show a name just a MAC address go to THIS site and type the MAC address in. It should at least give you the manufacturer, eg Apple, Toshiba etc so that you can narrow down those unknown ones.

It will be bridging somewhere on your network, that is the only thing that makes any sense.
 
PeterTheJet said:
Are you using Win 10?
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Thanks for the suggestion but none of our devices is running Win 10.

My neighbour's laptop was running Win 10 but when he brought it round to show me the network visibility issue he was very reluctant to let me touch it.
 
I have that modem/router - albeit in a cupboard. I'm using it's big brother on one of my connections, the TG589vac. You most definitely can access DCHP settings but you have to click an advanced settings button once you are on the correct page.

Not sure I can help a great deal, other than to say forget about channels, powerline adaptors or OS. If the suspicion is that an ethernet device of yours is rebroadcasting an insecure signal (neighbour is accessing via wifi, right?) then unplug each device in turn. Can you confirm neighbour is accessing via wifi and without the need for a password?
 
StewartR said:
If only.....

The user manual for my router is here: http://help.demon.net/files/2013/03/TG582n-User-Guide.pdf
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Ah, the ubiquitous Thompson / Technicolor TG582n, as found in millions of homes around the country (including mine, in a box somewhere). It does do DHCP, but as others have advised, you have to dig around for the settings. For a cheap plastic bit of tat, it's actually very flexible and configurable if you're prepared to get your hands dirty in a shell. I do not advise this though.

Changing the DHCP range is not solving the problem.
 
Have you got any guest networks open on your router?
 
owenb said:
Have you got any guest networks open on your router?
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Dunno. I've never knowingly set any up. (Remember, I don't know much about networks.) I guess that means the answer is no?
 
sometimes the default of the router is to have a guest network which is unencrypted who is your isp?
 
Interesting one...
  • The two networks are clearly bridged in some way.
  • That the neighbours devices are showing up on your wired network indicated, it is a device plugged into your wired network (or connected to a device plugged into your wired network) that is the bridge.
  • The fact that the issue is intermittent would indicate that perhaps the device in question is only intermittently active, which would perhaps indicate it is not your Powerline plugs themselves.
Are any of you wired devices susceptible to malware?
It is relatively trivial for a piece of malware to mimic a wifi named wireless network, but allow open connectivity to draw you in, as your wifi rather stupidly broadcasts the name of every SSID it has ever connected to by default; just listen in for the signal, create an phantom SSID with a similar name, leave it open and band, you've suckered someone in!
I'd be tempted to disconnect the wired devices and reconnect then one at a time and see if you can replicate the issue - including, those devices that are only occasionally used.
 
StewartR said:
I'm sorry, but I don't see how that's relevant. The list of my devices which my neighbour could see in Windows Explorer included a router, a Windows PC, a Sonos music player, an Amazon Fire TV stick, an Epson printer, a Loxone home automation server, and a TV set top box. I'm not sure that all of them even run OSs.
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Many devices today are built around Linux, including 4 of the devices you mention above.

Sonos: http://hackerboards.com/sonos-debuts-low-end-linux-powered-music-player/
Loxone: http://www.remotehomecontrol.co.uk/loxone-2/
Humax: http://wiki.hummy.tv/wiki/Custom_Firmware_Overview
Amazon: http://www.cio.com/article/2896576/...tv-stick-and-turn-it-into-a-media-center.html

It's worth checking if any of these contain or are somehow connecting to a WiFi adapter.
 
OK, I've spent the last hour running around the house, switching things on and off, trying to identify all the devices that are connecting to our network. I have some data but I'm not sure what to do with it.

I've used Fing on my Android phone to list connected devices, and I've logged in to the admin console on the router to list connected devices.

I have 13 devices [UPDATE - 14 devices] which I have been able to positively identify and which show on both lists. In every case I have positively confirmed the MAC addresses.
  1. 192.168.1.10 - Loxone Miniserver
  2. 192.168.1.65 - [WiFi] Android tablet
  3. 192.168.1.66 - [WiFi] Sonos music player
  4. 192.168.1.67 - [WiFi] Android phone
  5. 192.168.1.68 - [WiFi] Amazon Fire TV stick
  6. 192.168.1.71 - [WiFi] Epson printer
  7. 192.168.1.72 - desktop PC
  8. 192.168.1.199 - Telegesis Zigbee Communications Gateway - not sure what this is, but it's sitting there conencted to our router and I think it talks to our smart electricity and gas meters
  9. 192.168.1.200 - [WiFi] Android phone
  10. 192.168.1.201 - [WiFi] Sonos music player
  11. 192.168.1.202 - [WiFi] Amazon Kindle
  12. 192.168.1.203 - Humax TV set top box
  13. 192.168.1.204 - [WiFi] Amazon Kindle
  14. 192.168.1.254 - Technicolor TG582n router
So far so good.

However, Fing also lists 4 devices [UPDATE - 3 devices] which I can't identify:
  1. 192.168.1.1 - something manufactured by D-Link - not currently connected, but obviously must have connected since I installed FING this afternoon
  2. 192.168.1.64 - [WiFi] something manufactured by Digiboard Inc
  3. 192.168.1.99 - something manufactured by TP-Link - not currently connected, but obviously must have connected since I installed FING this afternoon - I've checked the MAC address and it's definitely *not* any of the three TP-Link powerline adapters which I'm using
And the Technicolor router lists 9 devices [UPDATE - 8 devices] which I can't positively identify
  1. 192.168.1.1 - 'Unknown-c0-a0-bb-1c-6b-38' - the MAC address confirms this is the D-Link device which Fing saw connected to this IP address (but doesn't think is currently connected)
  2. 192.168.1.1 - 'Unknown-14-cc-20-bc-9e-02' - the MAC address confirms that this is the TP-Link device which Fing saw connected at 192.168.1.99 earlier
  3. 192.168.1.2 - 'Bradfield-SonyB' - our neighbours' surname is Bradfield and his laptop is a Viao - I think this is his laptop
  4. 192.168.1.4 - 'Unknown-bc-30-7e-05-5a-08' - but the MAC address says it was made by Wistron Neweb Corp
  5. 192.168.1.5 - 'Bradfield-SonyB' - our neighbours' surname is Bradfield and his laptop is a Viao - I think this is his laptop
  6. 192.168.1.7 - 'Unknown-00-1f-16-f3-20-1d' - no idea what this is, but the MAC address says it was made by Wistron Neweb Corp
  7. 192.168.1.64 - 'Unknown-00-40-9d-62-28-9e' - the MAC address confirms this is the Digiboard device listed by Fing
  8. 192.168.1.179 - 'huaweistb' - I'm guessing this our neighbours' TalkTalk set top box
So - 22 devices in total.
14 which I can positively identify, and which are listed by both Fing and the router
3 which I think are our neighbours', and which were listed by the router but NOT by Fing
3 which I can't identify but which could well be our neighbours', and were listed by both Fing and the router
2 which I can't identify but which could well be our neighbours', and were listed by the router but NOT by Fing

I'm a bit confused by the fact that the router thinks more devices are connected than Fing can find. Any ideas what might be happening here?

And both methods have been able to find devices which I can't identify. Some of those listed by the router are definitely my neighbours'; the others probably are.

Have we learned anything from this?
 
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no wifi boosters or anything ( not sure if plusnet fit these)
 
Sejanus Aelianus said:
Many devices today are built around Linux, including 4 of the devices you mention above.

Sonos: http://hackerboards.com/sonos-debuts-low-end-linux-powered-music-player/
Loxone: http://www.remotehomecontrol.co.uk/loxone-2/
Humax: http://wiki.hummy.tv/wiki/Custom_Firmware_Overview
Amazon: http://www.cio.com/article/2896576/...tv-stick-and-turn-it-into-a-media-center.html

It's worth checking if any of these contain or are somehow connecting to a WiFi adapter.
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All of them apart from the Humax box communicate via WiFi. What does that tell us?
 
There is a thingy in some routers which sets wireless devices to being discoverable. There is also the wireles setup and DNLA type gubbins that would allow a device to connect too easily. If could be another near neighbour that has connected. I always change my router names so they aren't the default gibberish so it's obvious to anyone else it's not theirs.

If you want to stop it then you set your router to only allow your Mac addresses of your known devices to connect. I would also contact plusnet support and ask them whether other customers have the same issue as it could be a total foul up with the firmware on the router.
 
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