sjb - try resetting the mtu to a lower value on your netgear first, as that may cure it.
instructions here:
ask-leo.com/i_cant_access_some_websites_why.html
and alsomidway down the page, in the section headed "dr. tcp" at this tiscali link:
tinyurl.com/nd77y
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Thanks, Dalglish.
My MTU was set to 1300. Given that this is already lower than the 1492 example used as a starting point I have set the second choice of 576 and rebooted.
Will be amazed if this is the reason (Advertised ADSL performance has been pretty well spot on whenever checked and Cisco VPN never drops out), but I have nothing to lose, so stay tuned!
Cheers,
SjB
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Thanks for the suggestion, but within ten minutes of changing the MTU and rebooting I've had the problem twice; page unavailable, MSN drops out, but Cisco VPN still works fine.
Will set reset MTU (to 1492 as 1300 seems to be an oddball number).
Am open to trying other reasonable settings changes or calling BT if equipped with the info to hold my own in the conversation.
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but within ten minutes of changing the MTU and rebooting I've had the problem twice
>>
i used to get a similar loss of internet traffic when my "agnitum outpost" firewall was selected to block intruders ip on repeated attack scans. outpost then used to block all netgear traffic via 192.168.x.x for the set duration.
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Try DrTCP. See:
www.the-scream.co.uk/html/resources/adsl_tweaks.ht...l
Useful website re broadband tweaking:
www.speedguide.net/
- - - - - - - - - - - - - - - - - - - - -
What\'s for you won\'t pass you by
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SjB I am 99% sure this is caused by your physical connection. You are loosing synch momentarily and loosing the path, The VPN hangs on in there as its designed to do.
Its caused by high noise levels or low signal strength on the link. Does your netgear provide you with your DB signal strength levels?
------------------------------
TourVanMan TM < Ex RF >
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TVM is probably right, but there is also a possibility of interference in the wireless signal.
any other networks near you ? try changing the channel you use. Does it happen at specific times of day or coincide with anything else or does it seem random. Are you on a fixed rate connection or on dslmax ? is the phone wiring good or could there be a problem with socket or filters ?
lots of people report dropouts on dslmax esp while trsaining - its possible its trying to reset its max speed.
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Does your netgear provide you with your DB signal strength levels? ------------------------------ TourVanMan TM < Ex RF >
Yes it does:
in your web browser type
192.168.0.1
press entrer, then user name ADMIN, and your password.
Down the lefthand side of the screen under maintenance, click router status, then
at the bottom of the centre pane click show statistics.
My DG834G figures are upstream at 58dB line attenuation and 11 dB noise margin,
due to distance from the exchange, which is a bit on the thin side.
But it doesn't freeze as you describe.
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Try diasbling the Windows wireless zero configuration service, it cured that exact problem for me on my DG834G.. Go to control panel > Administrative tools > Services and find the above mentioned service. Right click it and stop it. Then from the drop down disable it. Wireless and internet access should be fine from then on. :-)
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Many thanks All for the kind suggestions.
Network strength:
For aesthetic reasons, the DG834G is hidden in an office cupboard (with a false back so it remains as cool as if worktop mounted). The T42 laptop is located 2 metres from it and the signal strength is always "Excellent".
Other networks:
I can "see" three other networks (and connect to two of them as I did in the week it took BT to hook mine up!). If other methods don't work, I will switch channels.
Line quality stats:
Connection speed: Downstream 2272kbps Upstream 288kbps
Line attenuation: Downstream 11db Upstream 2db
Noise margin: Downstream 17db Upstream 25db
Is this good, bad, or average please?
Windows wireless zero configuration service:
Now switched off.
I won't touch anything else until I learn that the problem still happens.
If it doesn't, I'll leave everything else alone and this switched off.
Thanks again and stay tuned; whatever the outcome I will report back.
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You'll have to actually disable the service by double clicking on it (Sorry if I didnt make that clear) and diasbling it from the pull down as well as stopping it, otherwise it will restart and cause problems. (Thats if it does cure your problem!!)
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If you disable the service permanently, the computer will not connect to the router when you turn it on. You would also have to turn off the DHCP service on your router, and allocate a fixed IP address on every device that attaches to it. Hassle.
Less hassle, should this turn out to solve your problem, would be to do the following:
Create a shortcut (right click and drag, select make shortcut) on your desktop or start menu to
C:\WINDOWS\system32\net.exe
then right click on it and change the target to read:
C:\WINDOWS\system32\net.exe stop wzcsvc
Now, when you run the shortcut, it will stop the service. Should you also want to be able to start the service again easily, make another shortcut and replace the word stop with start in the above target.
HTH
Gord.
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To my surprise, your suggestion appears to have solved the problem, Ross D; 24 hours later the problem hasn't manifested once whereas it was previously happening up to several times an hour. For the record as I tried changing it from the original value of 1300 down to 576, MTU is now set to 1500, this being the recommended value from the line test site that Stuartli kindly recommended (and which I have bookmarked).
As it happens, Gordon, I have already allocated fixed IP addresses to the five devices on the wireless home network (the router, three laptops, and a Canon WiFi printer) as it makes things like file transfer between devices very easy; simple shortcuts saved as IE Favourites suffice as a means of opening the destination folder). When troubleshooting or setting up guests (colleagues sometimes work from my home) it's also easier to know who's-who.
I have however created the shortcut you mention as an easy way of stopping the required service after startup when I'm working at the home office (the problem never occurs when I'm at any of our "office offices" worldwide and connected to our Corpnet)
Many thanks for all the help from all who offered it.
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Uh oh. :-(
I was too hasty; the problem has resurrected countless times today despite a check that the wireless configuration service is switched off.
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For comparison - 'my DG834G is a long way from the exchange and my figures are
ADSL Link Downstream Upstream
Connection Speed 3968 kbps 448 kbps
Line Attenuation 50 db 14 db
Noise Margin 13 db 23 db
I'm on dslmax.
Firmware V2.10.22
ADSL Firmware Version 3.02.06.00
uPnP off.
the diagnostics section of the router will do dns lookus / pings.
or try nslookup www.whatever.com from cmd on the laptop. tracert/ping dont neccesarily show useful stuff.
make a note of the ip address of a reliable site and try accessing it by ip address when the problem occurs, or put a suitable entry in the hosts file.
there was an xp issue with dns cache polution - cant remember the details but it did affect firefox. solved with ipconfig/flushdns
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oh yes - I get a static IP from my isp, I run nat and dhcp from the router but reserve addresses for some machines - its all in the options - means that the laptop allways gets the same ip at home but I dont have to fiddle with settings when I go elsewher e because its still done through dhcp.
are you seeing the router disconnect ? how long does it say its been connected ?
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Thanks, Mark.
My router is on later firmwhere releases than yours (V3.01.25 / ADSL 4.01.02.00) but I haven't found anything in later release notes about this version having troubles such as I experience.
UPnP is "on" but if worth a shot I will turn it off.
Will try your nslookup suggestion next time the problem happens.
I can't get a static externall IP address from BT as a home user, but as written above I do use fixed IP addresses for all internal connections on my network. Like you, however, I do also use DHCP.
Something I just found; looking through the DG's log files, I can see entries that appear to tally with when I have experienced the described problem. Using the timestamps to link related messages together, here are the last two occurences:
Tue, 2006-09-12 13:44:45 - LCP down.
Tue, 2006-09-12 13:44:46 - Initialize LCP.
Tue, 2006-09-12 13:44:47 - LCP is allowed to come up.
Tue, 2006-09-12 13:44:53 - CHAP authentication success
Tue, 2006-09-12 13:44:55 - Loss of synchronization :74
Tue, 2006-09-12 13:47:23 - LCP down.
Tue, 2006-09-12 13:47:24 - Initialize LCP.
Tue, 2006-09-12 13:47:24 - LCP is allowed to come up.
Tue, 2006-09-12 13:47:25 - Loss of synchronization :75
The "74" and "75" is a counter (I can trace sequentially back to 1) but what is this telling me, please?
I see there is no CHAP (Challenge-Handshake Authentication Protocol from a quick Google) entry for the second example above but don't know how relevant this is.
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SjB
thats your link going down.
LCP is the protocol that handles the connection.
Looks like you keep dropping out. could be a fault on the line, filters, house wiring etc,etc. Might be worth asking for a line test. - you could check the connection info again when it hapens though - see if the noise or attenuation are getting worse.
It could just be dslMAx playing its games. does it happen under particular circumstances - like pouring rain eg?
I would check your phone wires and filters, then ask for a line test and ask if interleaving is on or off on your line. (on makes it more reliable but slows your ping - prob only bother you for online games)
There is a 'fix' for noise problems that involves cutting one of the bt wires - the one that handles the ring signal - not needed with filters.
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www.kitz.co.uk/adsl/linestats.htm
exlains attenuation and has some sample figures.
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>>>exlains attenuation and has some sample figures.
Most interesting, ta, and bookmarked
For info I am now working through a set of questions with BT. Despite a concise description and the log file details I sent, I got what I believe to be a "standard" reply back; a majority were clearly answered by the original mail and it looks like the questions I have been asked are based on a simple keyword search without an ounce of thought being applied. Somewhat frustrating having taken the trouble to ask an intelligently crafted question to be treated like an oik who fired from the hip.
Anyway, I will go through the hoops for the questions that weren't answered in my original mail to BT, all to do with physical connection aspects; try another filter, try connecting without a filter, etc, etc.
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Ahh, the joy of customer service.
.*******
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Its gonna be your line. The fact its happened since you moved into a new place is a biggish clue.
------------------------------
TourVanMan TM < Ex RF >
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Indeed so, TVM, as shown by the LCP info in the log file, but what is odd is that my Cisco VPN client - which appears devoid of any keep-alive techniques - doesn't drop out, even though web browsing and MSN Messenger do.
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