Cisco 678 and NT4 server config

[BILL62]

Appreciate all tips and help on following. Currently have a client running a small NT 4.0 LAN. We have provided them
with a ADSL connection to the Internet using a Cisco 678 router/modem. We've configured this router to use
NAT (network address translation) to map his private LAN IP subnet to one of our global Internet IP address. In other words
all their PC's when accessing the Internet, will have their IP addresses translated in this router to our globally valid
IP address. This scenario works well except that now, the client wants to run a FTP server program on top of his NT 4.0
server that can be accessed from the Internet, and can also be viewed in "Network Neighborhood" of all their PCs on the LAN
at the same time to store files, etc. The LAN has only one segment and no other routers except this Cisco 678 that has a
primary purpose of routing traffic from the LAN to the Internet via ADSL connection. Setting up the NT 4.0 server
with one of our Internet valid IP addresses effectively takes this server out of the LAN segment and client advises that
he can no longer see this server in Network Neighborhood from any machines on the LAN.

From TCP/IP perpective, how do I continue to use NAT for all PCs on the LAN for Internet access, and at the same time, assign a static address translation of a fixed private address assigned to the server that is on the same same subnet as the rest of the PCs on the LAN to make it visible for the LAN PCs, and also use NAT to statically assign this server's private IP to one that is Internet valid for Internet visibility??

Thanks in advance.
Sam

 

[wybnormal]

This is not much different then a web site ai set up. You still use the private IPs and NAT. You set up a static NAT route that takes the public IP and maps the FTP ports through NAT to the IP of the FTP server. It does not matter that everyone in the LAN is on the same segment.

If you give the FTP server one of your addresses, then use IP HELPER-ADDRESS to move the ports for Trivial File Transfer Protocol, Domain Name System, Time service, NetBIOS Name Server, NetBIOS Datagram Server, Boot Protocol, and Terminal Access Controller Access Control System across the router, You can also use UDP FORWARD to move just the ports needed for the PDC and browser.

More about MS and Cisco routers are found at:

http://www.cisco.com/warp/public/473/winnt_dg.htm

Here is a link for everything you wanted to know about NAT but was afraid to ask

http://www.cisco.com/pcgi-bin/Support/PSP/psp_view.pl?p=Internetworking:NAT

Mike S

"Diplomacy; the art of saying 'nice doggie' till you can find a rock" Wynn Catlin