Would using VPN with IP pooling help here?  I don't know anything about
Cisco or PIX but my understanding is that the VPN client and PIX or VPN 3000
concentrator can have a VPN connection where the PIX or Concentrator assigns
an IP address to the client.  The aps on client then think they are at that
address and the decrypted packet on the inside has that "app address" as a
source address. Internal servers reply to the application address and
internal routing carries the packets to the PIX or VPN 3000 concentrator as
if it were just another internal router.

I'm going to call the IP address visible to the application the "App
Address" or AA and the externally visible network address the "Net Address"
or NA.  The PIX or VPN 3000 is the "Gateway".   What you have flow logic
wise is

Client OS/App sees AA as it's address
Packet encapsulated in Client NA
Gateway external NA receives packet and decrypts
Gateway Internal Address  sends decrypted packet with AA as source
Internal Server sees source as AA
Internal Server replies to AA
Packet gets routed to Gateway Internal Address
Gateway encrypts and encapsulates in external NA
Client receives on NA and unpacks the internal packet
The decrypted packet with AA as the destination address is passed up the IP
stack.

I think Check Point calls this Office Mode.

BTW, the reference to CA is for configuring a certificate authority and PKI.
I would suggest sticking with simple password authentication for testing the
encapsulation.

Adam

----- Original Message -----
From: "Fei Yang" <[EMAIL PROTECTED]>
To: "Jon Miles" <[EMAIL PROTECTED]>; <[EMAIL PROTECTED]>
Sent: Friday, April 26, 2002 10:05 AM
Subject: Windows domain login through PIX


Hello Jon,

I did some research on this issue, but unfortunately the answer is negative,
we can not have Win2k in DMZ to join into domains in the inside network.

To make it clear, here's the circumstance:
- Win2K server is in the inside network with the inside IP address of
x.x.x.x, and mapped to y.y.y.y in the DMZ side.
- Win2K client is in the DMZ side and trying to log in to the windows
domain. y.y.y.y is configured as the PDC.
- All IP ports are opened on PIX to allow traffic from DMZ go through to the
Inside network.

I make the conclusion by two ways.

Firstly, I used sniffer to monitor all traffics sent between the Win2K
client and Win2k server. The problem occurs on the third packet that the
client sent to the server. The destination address (server's address) of the
first two packets sent by the client was y.y.y.y, which is the server's
mapped address in DMZ. PIX translated y.y.y.y to x.x.x.x and sent the
packets to the server in the inside network. Win2K server also replied to
the client. However, the destination address of the third packet sent by the
client became x.x.x.x, which is the server's inside IP address. PIX won't
change this IP address and let the packet go through since there's no static
mapping for x.x.x.x in the DMZ side. As the result, the login process
failed.

I assume Win2k server sent back its inside IP address and host name to the
Win2k client, and then Win2K client began to use that inside IP address to
contact Win2k server. I tried to configure DNS doctoring and alias on PIX to
do translation, and tried to configure LMHOST and HOSTs file in Win2k client
directly to solve this problem, but none of them were useful. Win2k client
always uses x.x.x.x as the destination address of its third packet for the
domain login.

The second resource I got the conclusion is from a Microsoft security book,
I think it proves this login issue. There's one sentence in the book:

"You require a CA to run in the Demilitarized Zone (DMZ) where it can't
contact Active Directory. If the CA isn't able to connect to Active
Directory, then the CA must be configured as a Standalone CA."

Sorry for my poor English if I'm wrong and please correct me. My
understanding is that part of the sentence meaning is "Computers in DMZ
can't contact Active Directory, (which is not in the DMZ)".

Hope this helps.
Fei.


-----Original Message-----
From: Jon Miles [mailto:[EMAIL PROTECTED]]
Sent: Thursday, April 25, 2002 5:06 PM
To: Fei Yang
Subject: PIX logon


Fei,

Hi. I saw your question in a firewall mailing list regarding logging
onto a PDC from the DMZ - this is EXACTLY what I am trying to do. I see
the reply to your question is to use a syslog server, but frankly I
would prefer if you could just make it easy for me and tell me how you
solved this problem :)

Basically, I have a WIN2k workstation that cannot see the domain on the
other side. I have opened up all of IP for the meantime, and am using
NAT and static mappings. I can ping the global address of the PDC, so I
know the connectivity works. My guess is that you have to tell the
machine the IP address of the PDC, without it doing all the broadcasts.
I also, know you cannot pass these broadcasts across the PIX with a
helper address...
Any help would be appreciated.
Thanks.

Jon Miles
//Network Consultant

'delivering quality networking services'

web:       www.qosconsulting.net
mail:      [EMAIL PROTECTED]
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