[Asterisk-Users] Cisco, Sip, Linux, ISDN

[Mike Taht]

I am one of the few people left in the US with a ISDN connection to the 
internet. (Internet cable has been promised "Real Soon Now" for a couple 
years). Worse, my home network runs on a decrepit Cisco 2500 series 
router, and is double-natted via a firewall, which is why I currently 
use iax to call anywhere.

I have been making ever-increasing use of my asterisk PBX, and I'm ready 
to switch over to using it as my sole phone management system - but I'm 
faced today with trying to reduce complexity and/or improve reliability 
today, and add direct dialed SIP support....

1) I could add one or two isdn cards to a cisco 2600 I have in a box. 
I've looked over the sip support in the 12.3 release of IOS and it 
appears quite complete - and also quite complex.

http://www.cisco.com/en/US/products/sw/iosswrel/ps5187/products_configuration_guide_chapter09186a00801fa1d9.html

It's unclear to me how to configure dialout for local calls via 
asterisk, etc, etc, or whether the common ISDN module WIC-1B-U or ST or 
whatever is the "right thing" if I want to do both voice and data...

+s are the cisco is gonna stay up, and
-s are less control over the packet prioritization than I can get 
cleanly... and tons of IOS commands to figure out.

I keep thinking about adding additional isdn lines so I can get a touch 
more bandwidth and phone lines, and there are multiple 4-bri cards 
available for the 2600 on ebay - but that's not my first priority

2) I could add an isdn card to the Linux box. This seems to me to be the 
cleanest solution, I'd make my firewall also be the asterisk server, and 
hopefully gain some control of tcp flows that way to more highly 
prioritize voice traffic

+apparent simplicity, maybe fax support
-s it seems most of the ISDN cards in isdn4linux are not sold in the US, 
the technology is stagnant, and I'm less than enthused about statements 
like "Any CAPI based ISDN card will work" when I'd prefer something like 
ISDN card XXX tested on an opteron running kernel X.Y.Z, using 
multi-link ppp and and asterisk, no problems....

Any thoughts, sample configurations, other ideas?