Phase 1 parameters:

Pre Shared Key
Triple DES
SHA-1
300 sec
Diffie-Hellman Group 2
i.e. same as you

Both Win98se and Win NT4 clients are set up the same way.
I am about to upgrade the Win98SE client to Windows 2000 - will let you know
in a couple of days whether that has the big "hiccup" or not.

The firewalls we talk to are GB-1000, currently V3.2.1 and V3.2.2 - but the
"hiccup" performance appears to be the same for both.

I'm pinging a V3.2.2 site from my w98se client as I write this.  The usual
ping time is 57mS - but perhaps 20% of the time is is longer - several
hundred mS, and occasionally it times out (over 1 sec) - probably because
the site is fairly busy.  However it is clear watching the VPN log viewer
that the excessive ping times do not occur at either Phase 1 or Phase 2
renegotiation points.  It's not evident that the key renegotiations incur
any delay - at least, not on the basis of the current 15 minute snapshot of
traffic.

My colleague Andy will no doubt confirm that the significant "hiccups" seen
on a NT4 client do occur at the same time as the key renegotiation - if he's
listening ...

Regards,
�
-- Graham Jones
Linnet Solutions Ltd.
[EMAIL PROTECTED] <mailto:[EMAIL PROTECTED]>
01953 717605 or
077 74 894200
�



> -----Original Message-----
> From: Brian Fort (Mushkin) [mailto:[EMAIL PROTECTED]]
> Sent: 16 January 2002 07:19
> To: [EMAIL PROTECTED]; [EMAIL PROTECTED]; [EMAIL PROTECTED]
> Subject: RE: [gb-users] SA renewal causes Win2K Terminal Client
> disconnection
>
>
> I set the SA life parameter under "Authentication (Phase 1) >
> Proposal 1" to
> 537 seconds, and the SA life parameter under "Key Exchange (Phase II) >
> Proposal 1" to 600 seconds and I'm still encountering the same problem.
> However, I can at least now tell that the SA renewal for the
> Authentication
> Phase is taking 19-24 seconds.  The Key Exchange Phase took one second at
> most but usually wasn't noticeable.
>
> So this problem apparently has to do with the Authentication Phase.  I'm
> using 3DES encryption, Diffie-Hellman Group 2, and hmac-sha1.  Would
> changing any of these parameters possibly help?  Graham, what Phase I
> parameters do you have for that Win98 computer that only has 3-4 second
> "hiccups"?
>
> Also, I'm using GNATBox Flash 3.2.2 and I'm having this problem on both
> Windows 98 and Win2K Pro (Only OS's I've tried the client on).
>
> Thanks,
> Brian
>
>
> -----Original Message-----
> From: Graham Jones [mailto:[EMAIL PROTECTED]]
> Sent: Monday, January 14, 2002 9:09 AM
> To: [EMAIL PROTECTED]
> Subject: RE: [gb-users] SA renewal causes Win2K Terminal Client
> disconnection
>
> What platform are you running the mobile VPN client on?
>
> With the firewall running version 3.2.1 and a Windows 98SE running the
> client, we found that the VPN connection "hiccups" for two or
> three seconds
> every ten minutes or so, but with a Windows NT4 machine running the client
> the "hiccup" lasts a minute or more - again occurring every 10 minutes or
> so.  In the latter case a terminal services session will die and
> have to be
> restarted.
>
> With Firewall version 3.2.0 both client platforms suffered the more
> extensive hiccup.
>
> There is a recommendation to have different values for the SA
> life parameter
> in the authentication and key exchange proposals - e.g. 123 and
> 300 seconds.
>
> If you ping -t <target ip behind firewall> from a DOS window you
> can see the
> delays.
>
> Regards,
> �
> -- Graham Jones
> Linnet Solutions Ltd.
> [EMAIL PROTECTED] <mailto:[EMAIL PROTECTED]>
> 01953 717605 or
> 077 74 894200
>
>
>

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