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ISDN Switch Simulator on the Cheap?
smartmux wonders: "I've starting working on earning a CCNA certification, and part of the requirement for this cert and the 'professional' level cert is to know and understand how to install ISDN BRI circuits. Getting the Cisco router equipment to configure is easy and relatively cheap, but real ISDN lines or an off-the-shelf ISDN simulator is way too expensive. I'm not a *nix guy, so I thought I'd ask here -- is it possible to take an old PC, a couple of ISDN network cards, and an open-source PBX (like Asterick maybe) and make a simple ISDN switch to let my two routers talk?"
There are companies who rent time on systems that have all of the elements you might see on the test available. Here is only one of many examples http://www.thebryantadvantage.com/Rack%20Rentals.h tm/. Just do a google search for "rent time cisco ccna" and you'll have plenty of options appear. Probably a better use of time than setting up systems just for testing...but that's just my opinion.
Well, you guessed right, Linux can do this!
A few links:
Linux 2.6 and mISDN HowTo
PBX4Linux
Have fun!
RFC1925
Who uses ISDN in a new installation anyway?
Me, for one. Not exactly a new installation, but I just converted a bunch of E1 lines from R2 signalling to ISDN. It took about 4 hours, 3 of which were experimenting and testing to make sure the signalling was correct, then about 10 minutes to switch over each E1 and monitor call reliability. Next week I have to bring a whole system over to SS7, and start to convert the far end from R2 to ISDN. It's a standard Cisco job.
I'm not a big fan of the Cisco certs, but Cisco does know what is out there in the market. If you are naive enough to think the world is only DSL lines then I don't want you anywhere near my kit. When I see someone has earned their certs coupled with some equivalent work experience, I know they aren't going to break a network when I show them something new (meaning old and well established). The world is full of X.25 circuits, SNA, appletalk, ISDN, SS7, IpSec tunnels, but you will never have a real job working on Cisco with a bad attitude and obvious bias not to learn what's needed.
the AC
Hemos is like...sci-fi fans;he thinks technology is cool, but he hasn't bothered to understand the science it's based on
I studied for my CCNA by taking a CCNA prep course at the community college. For the price, I got tons of hands on time with the hardware. What they also supplied was a program called Boson NetSim from http://www.boson.com/. Think of it as a entire network simulator. Drag and drop routers, terminals, switches, and connections, then click to log in to any of them. The simulated hardware behaved the same as the real hardware we had, the downside being that we didn't have to troubleshoot bad cables, or someone using a cross or roll-over cable when we needed a straight-through.
Other then that, I over studied for the CCNA. I made sure I knew ISDN inside and out, and didn't get a single question on it. Tons on EIGRP, though. Just remember that the test is pretty random, and bad luck says you will get questions on what ever part it was you don't study for.