Every 60th ping is slow

I have a Windows Vista Ultimate desktop PC networked wirelessly to a router.
I sometimes connect to this PC from an XP Home laptop via RDP (which connects
wirelessly to the same router ). I found that these RDP sessions frequently
hang for several seconds, or simply time out.

In investigating this, I tried doing a "ping -t" from the Vista desktop to
the router. Most pings took 1-3 mS, but EVERY 60th ping took >1000 mS!

I've done the same test from the XP laptop, and all pings are reliably short.

So, something happens on my desktop each minute that slows the network down.
This would also explain the RDP hangs and timeouts.

The NIC has the latest drivers, and Windows Update says I am fully up to
date. And I can discount the router as the laptop does not have the same
problem.

What might the Vista PC be doing to slow the network down like this each
minute? What can be done to fix this?

On Mon, 19 Nov 2007 11:47:02 -0800, Fishyweb
<my.stephen.r.gunn.nose@remove.my.nose.googlemail. com> wrote:

>I have a Windows Vista Ultimate desktop PC networked wirelessly to a router.
>I sometimes connect to this PC from an XP Home laptop via RDP (which connects
>wirelessly to the same router ). I found that these RDP sessions frequently
>hang for several seconds, or simply time out.
>
>In investigating this, I tried doing a "ping -t" from the Vista desktop to
>the router. Most pings took 1-3 mS, but EVERY 60th ping took >1000 mS!
>
>I've done the same test from the XP laptop, and all pings are reliably short.
>
>So, something happens on my desktop each minute that slows the network down.
>This would also explain the RDP hangs and timeouts.
>
>The NIC has the latest drivers, and Windows Update says I am fully up to
>date. And I can discount the router as the laptop does not have the same
>problem.
>
>What might the Vista PC be doing to slow the network down like this each
>minute? What can be done to fix this?

The regularity of the symptoms suggests a router slowdown caused by selecting
802.1x authentication, when you don't have a RADIUS server.
<http://nitecruzr.blogspot.com/2006/10/wifi-authentication.html>
http://nitecruzr.blogspot.com/2006/1...ntication.html

If that's not it, I'd run Process Explorer, and NetStumbler. Watch to see if
any graphs show peaks when this slowdown is seen.
<http://nitecruzr.blogspot.com/2006/04/watching-what-your-computer-is-doing.html>
http://nitecruzr.blogspot.com/2006/0...-is-doing.html

--
Cheers,
Chuck, MS-MVP 2005-2007 [Windows - Networking]
http://nitecruzr.blogspot.com/
Paranoia is not a problem, when it's a normal response from experience.
My email is AT DOT
actual address pchuck mvps org.

I can confirm that 802.1x authentication is not set (the wireless NIC is
using WPA-Personal).

I'm not in a position to try Process Explorer right now, but will try to do
so in the next few days. Thanks very much for now.

"Chuck [MVP]" wrote:

> On Mon, 19 Nov 2007 11:47:02 -0800, Fishyweb
> <my.stephen.r.gunn.nose@remove.my.nose.googlemail. com> wrote:
>

>
> The regularity of the symptoms suggests a router slowdown caused by selecting
> 802.1x authentication, when you don't have a RADIUS server.
> <http://nitecruzr.blogspot.com/2006/10/wifi-authentication.html>
> http://nitecruzr.blogspot.com/2006/1...ntication.html
>
> If that's not it, I'd run Process Explorer, and NetStumbler. Watch to see if
> any graphs show peaks when this slowdown is seen.
> <http://nitecruzr.blogspot.com/2006/04/watching-what-your-computer-is-doing.html>
> http://nitecruzr.blogspot.com/2006/0...-is-doing.html
>
> --
> Cheers,
> Chuck, MS-MVP 2005-2007 [Windows - Networking]
> http://nitecruzr.blogspot.com/
> Paranoia is not a problem, when it's a normal response from experience.
> My email is AT DOT
> actual address pchuck mvps org.
>

I have now had the opportunity to try NetStumbler and Process Explorer (great
applications, BTW!) but unfortunately neither of them revealed any clue as to
what might be causing these network hangs. And I am not using 802.1x
authentication.

I'd certainly appreciate any further ideas you may have on tracing this
problem, as the problem is very frustrating!

"Chuck [MVP]" wrote:

> On Mon, 19 Nov 2007 11:47:02 -0800, Fishyweb
> <my.stephen.r.gunn.nose@remove.my.nose.googlemail. com> wrote:
>

>
> The regularity of the symptoms suggests a router slowdown caused by selecting
> 802.1x authentication, when you don't have a RADIUS server.
> <http://nitecruzr.blogspot.com/2006/10/wifi-authentication.html>
> http://nitecruzr.blogspot.com/2006/1...ntication.html
>
> If that's not it, I'd run Process Explorer, and NetStumbler. Watch to see if
> any graphs show peaks when this slowdown is seen.
> <http://nitecruzr.blogspot.com/2006/04/watching-what-your-computer-is-doing.html>
> http://nitecruzr.blogspot.com/2006/0...-is-doing.html
>
> --
> Cheers,
> Chuck, MS-MVP 2005-2007 [Windows - Networking]
> http://nitecruzr.blogspot.com/
> Paranoia is not a problem, when it's a normal response from experience.
> My email is AT DOT
> actual address pchuck mvps org.
>

On Tue, 20 Nov 2007 14:02:03 -0800, Fishyweb
<my.stephen.r.gunn.nose@remove.my.nose.googlemail. com> wrote:

>"Chuck [MVP]" wrote:
>

>I have now had the opportunity to try NetStumbler and Process Explorer (great
>applications, BTW!) but unfortunately neither of them revealed any clue as to
>what might be causing these network hangs. And I am not using 802.1x
>authentication.
>
>I'd certainly appreciate any further ideas you may have on tracing this
>problem, as the problem is very frustrating!

Process Explorer is a very configurable tool, you have to add additional metrics
(View - Select Columns) to really take advantage of its power. What metrics did
you look at?

--
Cheers,
Chuck, MS-MVP 2005-2007 [Windows - Networking]
http://nitecruzr.blogspot.com/
Paranoia is not a problem, when it's a normal response from experience.
My email is AT DOT
actual address pchuck mvps org.

Thanks for your continued interest in this, Chuck. To answer your question -
I was mainly looking at the CPU usage of the various processes, ordering the
processes with highest CPU consumers at the top. I was looking for a pattern
of a process leaping to the top each minute, co-inciding with the long ping
time. But I didn't spot a pattern of this type.

If you are able to offer some advice on how best to utilise Process Explorer
to investigate this, I'll be very happy...

"Chuck [MVP]" wrote:

> On Tue, 20 Nov 2007 14:02:03 -0800, Fishyweb
> <my.stephen.r.gunn.nose@remove.my.nose.googlemail. com> wrote:
>

>

>
> Process Explorer is a very configurable tool, you have to add additional metrics
> (View - Select Columns) to really take advantage of its power. What metrics did
> you look at?
>
> --
> Cheers,
> Chuck, MS-MVP 2005-2007 [Windows - Networking]
> http://nitecruzr.blogspot.com/
> Paranoia is not a problem, when it's a normal response from experience.
> My email is AT DOT
> actual address pchuck mvps org.
>

On Wed, 21 Nov 2007 12:04:01 -0800, Fishyweb
<my.stephen.r.gunn.nose@remove.my.nose.googlemail. com> wrote:

>"Chuck [MVP]" wrote:
>

>Thanks for your continued interest in this, Chuck. To answer your question -
>I was mainly looking at the CPU usage of the various processes, ordering the
>processes with highest CPU consumers at the top. I was looking for a pattern
>of a process leaping to the top each minute, co-inciding with the long ping
>time. But I didn't spot a pattern of this type.
>
>If you are able to offer some advice on how best to utilise Process Explorer
>to investigate this, I'll be very happy...

Start by looking at System Information, which you can see from the View menu.
See if there are any spikes visible there, corresponding with your problem.
Next, look at Context Switches, and Context Switch Delta, which is a more
granular version of CPU %. Also, the CPU History column will show you a
miniature graph of CPU use for each process.

--
Cheers,
Chuck, MS-MVP 2005-2007 [Windows - Networking]
http://nitecruzr.blogspot.com/
Paranoia is not a problem, when it's a normal response from experience.
My email is AT DOT
actual address pchuck mvps org.

Hi Chuck. I will try your suggestions in Process Explorer when I get home
later. However, I have been doing some Googling, and have found the following
2 links:

http://forums.whirlpool.net.au/forum...fm/677463.html
http://www.geekstogo.com/forum/Wirel...s-t101910.html

These both discuss the precise symptoms that I am suffering from, and imply
that the Wireless Zero Configuration service is the cause of the problem.
There are a number of suggestions in those links suggesting possible remedies
which I will try out. However, are you aware of this potential cause of
problems. And can you suggest a way of working without WZC in order to avoid
the problem?

"Chuck [MVP]" wrote:

> On Wed, 21 Nov 2007 12:04:01 -0800, Fishyweb
> <my.stephen.r.gunn.nose@remove.my.nose.googlemail. com> wrote:
>

>

>
> Start by looking at System Information, which you can see from the View menu.
> See if there are any spikes visible there, corresponding with your problem.
> Next, look at Context Switches, and Context Switch Delta, which is a more
> granular version of CPU %. Also, the CPU History column will show you a
> miniature graph of CPU use for each process.
>
> --
> Cheers,
> Chuck, MS-MVP 2005-2007 [Windows - Networking]
> http://nitecruzr.blogspot.com/
> Paranoia is not a problem, when it's a normal response from experience.
> My email is AT DOT
> actual address pchuck mvps org.
>

On Thu, 22 Nov 2007 04:41:01 -0800, Fishyweb
<my.stephen.r.gunn.nose@remove.my.nose.googlemail. com> wrote:

>"Chuck [MVP]" wrote:
>

>Hi Chuck. I will try your suggestions in Process Explorer when I get home
>later. However, I have been doing some Googling, and have found the following
>2 links:
>
>http://forums.whirlpool.net.au/forum...fm/677463.html
>http://www.geekstogo.com/forum/Wirel...s-t101910.html
>
>These both discuss the precise symptoms that I am suffering from, and imply
>that the Wireless Zero Configuration service is the cause of the problem.
>There are a number of suggestions in those links suggesting possible remedies
>which I will try out. However, are you aware of this potential cause of
>problems. And can you suggest a way of working without WZC in order to avoid
>the problem?

One of the discussions about the problem suggests that the vendor of the WiFi
adapter has to release a WiFi client manager to replace WZC, similar to what
they have for Windows XP. I don't use WZC on my Windows XP laptop, I use the
Intel client, and it does fine.

It should be easy enough to test. Just establish a connection with the router
(keep pinging a server on the Internet for instance), then disable WZC. Short
of disabling WZC itself, you could try to disable its need to retry for a more
preferred connection so often. So say the folks in the various discussions,
though I don't see so many folks actually saying that their changes accomplished
what they need.

There was a Vista update, which supposedly included WiFi improvements. If you
haven't applied this update, you might want to do so.
<http://nitecruzr.blogspot.com/2007/10/windows-vista-is-maturing.html>
http://nitecruzr.blogspot.com/2007/1...-maturing.html

--
Cheers,
Chuck, MS-MVP 2005-2007 [Windows - Networking]
http://nitecruzr.blogspot.com/
Paranoia is not a problem, when it's a normal response from experience.
My email is AT DOT
actual address pchuck mvps org.

I eventually found the solution. I found a more recent driver for my WLAN
card at the Ralink web site. This by itself did not fix the problem. But
using the WLAN Optimizer program and this driver together solved it! I'm very
relieved and happy to have finally gotten on top of this. I hope this info is
of use to others.

"Chuck [MVP]" wrote:

> On Thu, 22 Nov 2007 04:41:01 -0800, Fishyweb
> <my.stephen.r.gunn.nose@remove.my.nose.googlemail. com> wrote:
>

>

>
> One of the discussions about the problem suggests that the vendor of the WiFi
> adapter has to release a WiFi client manager to replace WZC, similar to what
> they have for Windows XP. I don't use WZC on my Windows XP laptop, I use the
> Intel client, and it does fine.
>
> It should be easy enough to test. Just establish a connection with the router
> (keep pinging a server on the Internet for instance), then disable WZC. Short
> of disabling WZC itself, you could try to disable its need to retry for a more
> preferred connection so often. So say the folks in the various discussions,
> though I don't see so many folks actually saying that their changes accomplished
> what they need.
>
> There was a Vista update, which supposedly included WiFi improvements. If you
> haven't applied this update, you might want to do so.
> <http://nitecruzr.blogspot.com/2007/10/windows-vista-is-maturing.html>
> http://nitecruzr.blogspot.com/2007/1...-maturing.html
>
> --
> Cheers,
> Chuck, MS-MVP 2005-2007 [Windows - Networking]
> http://nitecruzr.blogspot.com/
> Paranoia is not a problem, when it's a normal response from experience.
> My email is AT DOT
> actual address pchuck mvps org.
>