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jgrove
17-06-2011, 22:59
My wife arrived home to find a VM man outside out house (not on our property) with an aerial and meter in his hand claiming we had a leakage effecting wireless networks in the area? Claiming we had to much power causing problems to other users. Not sure why as we have a standard protected wireless network in our house provided by a netgear srxn3205 router. Our reading was 215? however my wife pointed out that the man who lives next door is a techno geek and we knew he had cable and he spends most of his life in his room plugged into the net, the man then moved towards there house where the reading was over 500?

Can anyone shed some light on what this all means and how the ended up outside my house?

Cheers

Milambar
17-06-2011, 23:02
Also, your wireless is none of VM's business. You could crank up the power on the wifi (if that were actually possible) to crystal palace standards, and it'd still not be VM's business. Though you might get a visit from some other authorities.

Kymmy
17-06-2011, 23:06
RF is very notorious to track down, without really decent tracking equipment you can believe you have the source then it'll turn out to be bouncing off buildings and will be elsewhere..

Your neighbour probably has an imported 2.4ghz device that exceeds UK power limits ( I have a few devices like that but only use them at events for video transmission over a few hundred meters;) ) The overpowered and a lot of times unfiltered devices can interfere with other users to a point where the signal of some cheaper routers can be swamped making them totally unusable...

It's not though normally upto VM to track these down and legally they can't do sod all apart from reporting the offender to OFCOM

TJS
17-06-2011, 23:07
Also, your wireless is none of VM's business. You could crank up the power on the wifi (if that were actually possible) to crystal palace standards, and it'd still not be VM's business. Though you might get a visit from some other authorities.

Nah; you need a license to cover long distance

Graham M
17-06-2011, 23:07
Correct, that doesn't stop anyone from doing it

Kymmy
17-06-2011, 23:11
I do have a 50w amp that will cover that frequency sat on the shelve :D Never used it on 2.4Ghz but works well on 2.3Ghz

Graham M
17-06-2011, 23:13
You could resell Wireless Broadband :p: , 50W that would cover... 10 miles of reasonably hilly ground?

Kymmy
17-06-2011, 23:16
If I sit on top of the local hill with a small yagi I can get about 80 miles with speech :D

jgrove
17-06-2011, 23:16
So it would seem that my neibough is using an overpowered wireless system for use in the uk? hence why my network often stops working? I am unsure what happended next as he said he needed to see what services they had and then get permsion from them to go on there property?

All seems a bit odd unless someone has complained to VM?

Graham M
17-06-2011, 23:18
Probably nothing as it is nothing to do with Virgin

Kymmy
17-06-2011, 23:24
Still doesn't matter, might not even be a router, could be phone, video sender, baby monitor or even a microwave..

He's got no reason to talk to the VM person even if he's a VM customer..

ONLY way to deal with it is to report the interference to ofcom who will send someone to investigate

jgrove
17-06-2011, 23:29
Seems weird that VM even cam out then?

Milambar
17-06-2011, 23:32
Very weird indeed.

Kymmy
17-06-2011, 23:34
Probably doing a local install and wondered why the customer couldn't get wifi on their hub

qasdfdsaq
17-06-2011, 23:34
Interference from wireless should have no effect on VM's network. More likely they're talking about cable interference, i.e. on the coax line. Engineers going out to track these down is a common thing to improve everybody's service.

Milambar
17-06-2011, 23:44
That would make more sense indeed.

jgrove
17-06-2011, 23:49
So it would appear that one of us or both have a break in the cable that runs from the street cab to the house?

Cheers

Graham M
18-06-2011, 00:22
Not necessarily, it could just be some equipment putting interference back down the line

Sephiroth
18-06-2011, 01:00
Graham_M has got it right. The man isn't looking for wifi, he's looking for the source of obvious noise injection to the cable system. I'd say that a lot of people's upstream is running at QPSK and having further difficulties.

VM are monitoring each CM in real time AFAIK and can be reactive to an area or locality issue that's thrown up.

jgrove
18-06-2011, 09:58
Graham_M has got it right. The man isn't looking for wifi, he's looking for the source of obvious noise injection to the cable system. I'd say that a lot of people's upstream is running at QPSK and having further difficulties.

VM are monitoring each CM in real time AFAIK and can be reactive to an area or locality issue that's thrown up.

Not sure what QPSK means? Is it an error correction system?


Does it mean i have a break in the cable?

Cheers

Graham M
18-06-2011, 10:33
QPSK (Quadrature Phase Shift Keying) and QAM (Quadrature Amplitude Modulation) are Modulation methods, IE ways of sending digital signals down the wires over distance whithout the signal degrading too much, IE that it is still recognisable for what it started out as when it reaches the other end of the cable.

on in an hour!
18-06-2011, 12:34
heres the reason (simply put) that the VM network engineer was in your garden:
VM's system (nothing to do with wireleess transmissions) can leak RF into other systems using the same transmission freqs,which can degrade their service,a particular worry is leakage (egress) into (ingress) a close-by emergency services system.
they are legally bound and monitored by OFCOM to keep the leakage under certain criteria.each principal technician from the service side of VM has a monitor (manufactured by TRILITHIC for these purposes) in his van which picks up 'hotspots' of leakage from VM's network.

these guys then park up at the office or stores where it downloads its info.this info is then transferred onto a map with its measurements,the high leakage points then have a fault ticket raised which goes to a network engineer to investigate.
they have small handheld RF 'sniffers' which generally locate the leakage,but for awkward jobs theres a bigger aerial type device they use.

typically its unterminated connections on the network that are egressing but it can be an open-ended cable in a customers house or an output on a splitter or an open box on the front of a house with an unterminated cable in.

these cases of course are reliant on the 'drop' cable still being connected to the network.
hope this helps ;)

Sephiroth
18-06-2011, 14:21
Or noisy fridges, electric drills, stair lifts .......

jgrove
18-06-2011, 17:17
Thanks for the replies, having looked at my VM connections, none are unterminated and all are done up, one to the tv box and one to the cable modem.

Kymmy
18-06-2011, 17:23
heres the reason (simply put) that the VM network engineer was in your garden:
VM's system (nothing to do with wireleess transmissions) can leak RF into other systems using the same transmission freqs,which can degrade their service,a particular worry is leakage (egress) into (ingress) a close-by emergency services system.
they are legally bound and monitored by OFCOM to keep the leakage under certain criteria.each principal technician from the service side of VM has a monitor (manufactured by TRILITHIC for these purposes) in his van which picks up 'hotspots' of leakage from VM's network.

these guys then park up at the office or stores where it downloads its info.this info is then transferred onto a map with its measurements,the high leakage points then have a fault ticket raised which goes to a network engineer to investigate.
they have small handheld RF 'sniffers' which generally locate the leakage,but for awkward jobs theres a bigger aerial type device they use.

typically its unterminated connections on the network that are egressing but it can be an open-ended cable in a customers house or an output on a splitter or an open box on the front of a house with an unterminated cable in.

these cases of course are reliant on the 'drop' cable still being connected to the network.
hope this helps ;)

Weird then that the OP stated that the techs words were to the effect that the leakage was interferring with wifi and caused by too much power..

Unterminated transmission lines wouldn't effect a band over 1.5Ghz up (even it's harmonics would be limited)

So would this be the tech trying to dumb it down??

qasdfdsaq
20-06-2011, 04:29
Could be, yes. Too many people associate "wifi network" with "the internet" without any understanding of whats on the other end of the wifi link and a lot of IT professionals are trained to dumb it down to the level of common folk.

Kymmy
20-06-2011, 11:14
I know I used to dumb it down when doing 3rd and 4th line but I've never given them an excuse which is nothing to do with the problem even when I needed to dumb it totally down..

Perhaps it's a dumb down that doesn't put the fault on the cable ;) :D

qasdfdsaq
20-06-2011, 17:38
Like I say, you'd be surprised how dumb the average consumer has got over the last few years... What with technology being so much more accessible, cheap, and easy to use nowadays.

I remember the days when I had to use telnet to get my wireless network set up correctly, now it's plug in superhub and expect everything to just work. Or don't even do that, since engineer plugs in superhub for you on some installs...