I am very interested in the DACs capabilities of Digium cards, there is no information anywhere on this. I could always do pri bridging via libpri like you suggest however. But having hardware handle the bridging onboard a single PCI card would help reduce my server requirements for a final product, as long as I can spy on active channels somehow. I don't think its going to work that way, I wil test out libpri for a bit.
Shane+ On 1/28/07, Leo Ann Boon <[EMAIL PROTECTED]> wrote:
Shane Spencer wrote: > I am trying to do a wire level tap on T1 equipment using digum > equipment. So far most call monitoring hardware for call centers try > to stay on the analog side requiring a lot of rewiring. I have > already posted to the list about T1 "bridging" using DAC's support in > the zaptel drivers. I still don't know if I can spy on channel > information since I don't have any digium hardware on me until the > project begins. > There are a number of systems using ISDN digital taps. The proper way requires a high impedance bridge - you don't want to load the line that you're tapping. > Anybody found a method of spying on a D-Channel and all voice channels > using standard T1 equipment? I am making a rough assumption that if I > can trick the zaptel drivers into operating without anything > responding to a TX signal then I can do the following: You can directly bridge the 2 ports and extract what you need as you bridge - see pridump.c in libpri. You don't even need asterisk, just the zaptel and libpri. The only problem with this approach, is that the bridge becomes a point of failure. Your box down, your PRI goes down as well. > > S-T1 = T1 to Spy On > T1-1 = Digium T1 card #1 > T1-2 = Digium T1 card #2 > > Map S-T1(RX) to T1-1(RX) and S-T1(TX) to T1-2(RX) and decode the > D-Channel where appropriate, should I be able to spy on the RX/TX > channels enough to make a recording including CID information? This > would help in situations where the monitoring system needs to be > replaced or taken down without bothering in-progress calls. This is technically correct, but I don't know how well it works. Eicon recommends a similar technique to do monitoring with their Eicon Server cards. For the BRI, it's done this way. But for the PRI card, they actually suggest using a custom cable. Eicon cards have a special Hi-Z monitoring mode to support this application. http://www.eicon.com/worldwide/solutions/How_To_Call_Tapping_and_Monitoring_with_Diva_Server FYI, Voicetronix has a Hi-Z version of their OpenPRI card that work with an open-sourced voice logging application available from their site. Leo _______________________________________________ --Bandwidth and Colocation provided by Easynews.com -- asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
_______________________________________________ --Bandwidth and Colocation provided by Easynews.com -- asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
