Hi all,
as a WISP, I've several customers that ask me for ISDN backup to wireless connection. To achieve this an ethernet router with and ISDN interface is needed in addiction to the normal wireless CPE. The router simply check if the wireless connection is ok (watchdog on PPPoE access concentrator) and if this goes down, ISDN dial-up starts. This can be done with Cisco (e.g. 1841, 1721 with eth WIC set as WAN and ISDN as backup) or with MK (http://www.mikrotik.com/testdocs/ros/2. ... e/isdn.php). Due to the fact that only PCI ISDN card support is provided, MK solution must be done with a normal PC and routerboard cannot be used. Obviously RB based solution will be better (smaller, fanless, easly customizable, ...) but no miniPCI ISDN support is provided...

I have done this with ISDN routers behind a ethernet port. Unfortunally, MT thinks ISDN is going by the wayside, so there is not really going to be much more support for ISDN in the future.

Dennis Burgess
St. Louis Network Engineering Services
http://www.mikrotikconsulting.com
dmburgess@mikrotikconsulting.com
Certified Mikrotik Engineer

Thank you gmsmstr,
of course ISDN is not a technology "future proof", but as backup is has a reason to "survive".
Could you please address me to some commercial product that can solve the problem? I think that Cisco 1840 series should solve it, with an eth and an ISDN WIC, but customers look for a cheaper solution.
MK is a good solution, but it is not so "elegant" to place a PC performing as router at customer's site...
Rgds

I use 532s all the time in indoor boxes, love them, cheap, 200 bucks.

As far as your ISDN solution, you are right, for backup, it would be great, but limited support really stinks. I could see where it is useful. I would look for some sort of REALLY CHEAP, ISDN interface, maybe a router, but really cheap, then back it up with the 532

Dennis