ISDN backup line

Hey guys, here is my problem.
At work we have a crappy ADSL line (384Kbps) and I would like to implement a backup ISDN line, the router that we use is a Zyxel Prestige ADSL Modem/router which doesn't support this feature. Do you have any solutions to suggest? I was thinking maybe of a linux/unix router with an isdn modem on it, is this possible? If not suggest any mid-range (not to expensive) routers that support an ISDN backup line.
Thanx...

To Me It Be Easyer To Just Get A Router But Im Selling 2 Of Them But There Is Places You Can Go To Get Them Like UsedRouters.com Thast Used Though Or You Can Go Buy Brand New Ones. Like I Said I am selling 2 routers! They supposrt a ISDN Backup Line, And There Brand New. I Got Them And I Never Decided To Use Them.

1)3Com OfficeConnect Remote 521 High Speed ISDN Connectivity for Data and Voice $995.00

2)Pipeline® 50 Ethernet-to-ISDN Router $500

If interested get back but go to UsedRouters.com There kinda average price but really good.

Good Luck!

You can buy a router as lilmisscompgenius has suggested or use IPCOP. IPCOP is a free linux firewall distribution that can be installed on any old Pentium with about 32MB RAM and a 1GB HD. The easiest way would be to setup two IPCOPs. One connected to ADSL with the connected to your ISDN line. Set up the ADSL IPCOP as the default gateway, with the other IPCOP as a secondary, and you've got an automatic backup system for the cost of two old PCs and setup time.

If you've got the cash though, go for the router. I love my IPCOP though.

Thanx for the reply guys, as i said i would like to avoid buying a new router and especially a bit expensive one. I have an ipcop box setup and i was thinking about setting it up to dial-on-demand when the adsl line is down. Has anyone tried this with an ISDN modem?

There are quite a few ways you can get a ISDN backup to work and this could be done without IPCOP or in conjunction with it.

Using simple routing protocols such as RIP or IGRP (or even OSPF), you'll be able to have two different gateways (one being your ADSL connection and the other being the ISDN router/dialup) with different metrics.

When the ADSL router goes down and the routing protocol updates your Linux server, you would then have the ISDN connection come up automatically without causing much problems.

Again, requirement for the above to work would be a common routing protocol on your ADSL router, Linux box and whatever device would be in charge of the IDSN backup line (possibly the Linux box itself).

Hope this helps.

Cheers,

I have an ipcop box setup and i was thinking about setting it up to dial-on-demand when the adsl line is down. Has anyone tried this with an ISDN modem?

You can't actually setup an IPCOP box to automatically switch over from ADSL to dial-on-demand ISDN on the same box, as you can only have one "red" interface. You can do it manually i.e. bring the network down, swap over to ISDN and bring it up again, but you I assume you want an automatic changeover.

For that you will need a second IPCOP with the ISDN "red" interface.