Problem: High WLAN activity

Our network consists of one accesspoint (802.11b), and about 25 connected
clients. About half of the clients uses a Linksys WET11, the other half uses
the Senao 2511.
From time to time all clients see high WLAN activity (blinking led), even if
the LAN side of the client is not connected. Using another AP (Senao SL-2511
AP PRO plus) doesn't solve the problem:-(
At the the high WLAN activity latency time increases so much, that it is
almost impossible to browse the internet. As a possible solution, all
clients are set to a maximum of 2 MB/s. This didnt solve the problem either.

Anyone an idea?


Kind reagrds,

Marcel


--
Posted by news://news.nb.nu

Is the network secured with encryption either WPA or WEP. If you are using
WEP make sure it is not Open System or AUTO, it should be Closed System.
Then you could also use MAC address filtering.

If it isn't a security issue then I am not sure. I was just thinking you may
have a freeloader who is downloading.

Nite Rider
"Marcel Joustra" <(E-Mail Removed)> wrote in message
news:412ecf64$(E-Mail Removed)...
> Our network consists of one accesspoint (802.11b), and about 25 connected
> clients. About half of the clients uses a Linksys WET11, the other half
uses
> the Senao 2511.
> From time to time all clients see high WLAN activity (blinking led), even
if
> the LAN side of the client is not connected. Using another AP (Senao
SL-2511
> AP PRO plus) doesn't solve the problem:-(
> At the the high WLAN activity latency time increases so much, that it is
> almost impossible to browse the internet. As a possible solution, all
> clients are set to a maximum of 2 MB/s. This didnt solve the problem
either.
>
> Anyone an idea?
>
>
> Kind reagrds,
>
> Marcel
>
>
> --
> Posted by news://news.nb.nu

On Fri, 27 Aug 2004 07:58:38 GMT, Nite Rider spoketh

>Is the network secured with encryption either WPA or WEP. If you are using
>WEP make sure it is not Open System or AUTO, it should be Closed System.
>Then you could also use MAC address filtering.
>
>If it isn't a security issue then I am not sure. I was just thinking you may
>have a freeloader who is downloading.
>

Actually, if you are using WEP, you should use Open System because
Closed System exposes your WEP keys...

If you're using WPA, it doesn't matter, as the keys are not used for
authentication.

Since it sounds like a business, I'd suggest looking into using a Radius
server to authenticate all the connections to the wireless network.

Lars M. Hansen
http://www.hansenonline.net
(replace 'badnews' with 'news' in e-mail address)

"Marcel Joustra" <(E-Mail Removed)> wrote:
>clients are set to a maximum of 2 MB/s. This didnt solve the problem either.

What's your broadband speed? At 25x2, you are requiring 50 megabits
of bandwidth....

Maybe a machine or a number of machines are all hitting the net at
once silently for vrus updates or WinUp or something...

"Nite Rider" <(E-Mail Removed)> schreef in bericht
news:OQBXc.52987$9d6.14072@attbi_s54...
> Is the network secured with encryption either WPA or WEP. If you are using
> WEP make sure it is not Open System or AUTO, it should be Closed System.

No it is not secured by WEP or WPA. All connections through the air are VPN
encrypted tunnels.....

> Then you could also use MAC address filtering.
>

We know, but discovered that intruders begin to fake MAC addresses of
regular clients.



> If it isn't a security issue then I am not sure. I was just thinking you
may
> have a freeloader who is downloading.
>


That's what i was thinking of. But if there is a free downloader, why should
the WLAN led on all the other customers blink heavily? If there is traffic
from the AP to one of the clients, other clients should not have blinking
wlan leds.....? Or could this be the case if they use other protocols then
tcp/ip (like netbios?)


Marcel


--
Posted by news://news.nb.nu

"Lars M. Hansen" <(E-Mail Removed)> schreef in bericht
>
> Actually, if you are using WEP, you should use Open System because
> Closed System exposes your WEP keys...
>

> If you're using WPA, it doesn't matter, as the keys are not used for
> authentication.
>

we don't use both.

> Since it sounds like a business, I'd suggest looking into using a Radius
> server to authenticate all the connections to the wireless network.
>


We have a radius server to allow encrypted tunnels from the AP to the
internet. But the way is clear for clients to generate traffic from or to
the AP...(to other clients)


Marcel


--
Posted by news://news.nb.nu

<William P.N. Smith> schreef in bericht
news:(E-Mail Removed)...



>
> What's your broadband speed? At 25x2, you are requiring 50 megabits
> of bandwidth....
>
> Maybe a machine or a number of machines are all hitting the net at
> once silently for vrus updates or WinUp or something...
>

Maximum for this AP is 5 mbit/s But we can monitor on the DSL interface that
this speed (at the moment the problem occurs) is only 1-2 mbit/s (and
dropping down because no clients are able to communicate on a normal way to
the accesspoint)


Marcel


--
Posted by news://news.nb.nu

On Fri, 27 Aug 2004 22:51:22 +0200, Marcel Joustra spoketh

>
>"Lars M. Hansen" <(E-Mail Removed)> schreef in bericht
>>
>> Actually, if you are using WEP, you should use Open System because
>> Closed System exposes your WEP keys...
>>
>
>> If you're using WPA, it doesn't matter, as the keys are not used for
>> authentication.
>>
>
>we don't use both.
>
>> Since it sounds like a business, I'd suggest looking into using a Radius
>> server to authenticate all the connections to the wireless network.
>>
>
>
>We have a radius server to allow encrypted tunnels from the AP to the
>internet. But the way is clear for clients to generate traffic from or to
>the AP...(to other clients)
>
>
>Marcel

If you have a radius server, then I strongly suggest that you consider
using either WEP with Radius authentication or WPA with Radius
authentication. It will definitely keep the intruders out, assuming you
have a strong password policy in place.


Lars M. Hansen
http://www.hansenonline.net
(replace 'badnews' with 'news' in e-mail address)

"Lars M. Hansen" <(E-Mail Removed)> schreef in bericht

Hi Lars (<g> name of my son:-)

> If you have a radius server, then I strongly suggest that you consider
> using either WEP with Radius authentication or WPA with Radius
> authentication. It will definitely keep the intruders out, assuming you
> have a strong password policy in place.
>

Ok, but if the problem is not an intruder, but one of my clients? I have to
determine the problem first, before i have the solution.

What do you (or anyone else) think of the fact that all WLAN leds on all
clients are blinking heavily? (not all the time, just for 1-60 minutes, like
some big transferring is going on). On normal tcp/ip only the wlan led of
the client receiving or sending is blinking, not on a client who doesn't
have traffic. What causes this blinking on other clients? Netbios? Other
protocols?


Marcel.


--
Posted by news://news.nb.nu

On Fri, 27 Aug 2004 23:38:52 +0200, Marcel Joustra spoketh

>
>"Lars M. Hansen" <(E-Mail Removed)> schreef in bericht
>
>Hi Lars (<g> name of my son:-)
>
>> If you have a radius server, then I strongly suggest that you consider
>> using either WEP with Radius authentication or WPA with Radius
>> authentication. It will definitely keep the intruders out, assuming you
>> have a strong password policy in place.
>>
>
>Ok, but if the problem is not an intruder, but one of my clients? I have to
>determine the problem first, before i have the solution.
>
>What do you (or anyone else) think of the fact that all WLAN leds on all
>clients are blinking heavily? (not all the time, just for 1-60 minutes, like
>some big transferring is going on). On normal tcp/ip only the wlan led of
>the client receiving or sending is blinking, not on a client who doesn't
>have traffic. What causes this blinking on other clients? Netbios? Other
>protocols?
>
>
>Marcel.

Wireless traffic is "broadcast", so all wireless clients will see
everything, but only accept the traffic which has a destination address
matching their MAC address. That's why all clients will flash even if
only one of them are actually actively moving data across the wireless
network.

Lars M. Hansen
http://www.hansenonline.net
(replace 'badnews' with 'news' in e-mail address)