Networks

install the shared modem service that comes with SBS 2003.

see if you have the means (password) to get into the router. you shouldn't have to but just see if you do. call your isp for help if you don't.
also, do you know the ip address of the router? if not you can find that out via the interface of the router so good excuse to call the isp anyhow. if they say 'no support' don't worry write down model number of router and go to mfg website.
So you are saying this works for one computer only now yes?
you can share this one like a broadband connectioon. plug everybody into a common switch and you should have the internet everywhere.
if not you probably have a dhcp problem or you need to lock nics down to 10mb half duplex for that older router maybe. start by trying to ping the isdn router. if you can ping it but no internet, do ipconfig /release /renew also. you may have firewalls on your xp clients that need to allow the internet also...

Try Using Internet Connection Sharing. This is built into SBS. You can chose to have the connection always on or dial as need. Make sure that the ISDN line is under an unlimited dialing plan from your provider.

Techknow Dude

for a hardware solution you have to "look" into the isdn modem/router . otherwise don't you have the RRAS interface to use . first use the wizard then go in and configure manually .

in other words, treat it link broadband.
is this set up now? or are you setting it up.
get help from your isp's techsupport to set it up. get a router that you can find the manual for.

I havent come right with this because there is no way of controlling the dial up.
i installed Lansuit602 and used it as a proxy server, this has done the job,.

You have few options.

SMC Barricade? SMC7004BR
4-port 10/100 Mbps Broadband Router

This is a router that has a serial port on it that will control a ISDN modem.

You could also use a combination modem/router like the Cisco 813.

Lee