Your experiences on PRI ISDN interface


#1

Well, alongside my other set of posts, i’ve found out T1 isn’t even available, and my project for the hotel will have to rely on Primary Rate ISDN.
And what Telecom New Zealand have told me is that the Primary Rate ISDN is roughly 2Mbps, and can support upto 30 64kbps channels, so 4 PRI ISDN will be sufficient for the mean time.
So my question is:
With the Wildcard TE410P/Wildcard TE411P, will i be able to connect all 4 PRI ISDN lines into this card, and have asterisk be able to recognise and use all 120 channels?
or is it a little more complex than that?(Newbie but learning)


#2

At my company’s testbed we’re using these cards and yes, it can handle 120 calls. We have one machine which contains 2 of this card and therefore has 240 lines, and it’s working too. For the 240 lines at the same time it was enough one Intel Xeon at 3000MHz and the CPU load was around 60%. (Just for reference on the CPU utilization.) Anyway, if you have more questions about this, just post it in this topic, because I’m monitoring it. Have fun! :wink:


#3

Could you please tell a litle bit more about those 240 phonecalls. Did you have hardware or software echo cancelation? Did you have codec translation? Did you record any call? And how much established phone calls did you have in one min? Did you use “reinvite=yes”?


#4

Actually I don’t know if our cards support hw. echo cancellation, but in zapata.conf we have both ‘echocancel’ and ‘echocancelwhenbridged’ set to ‘yes’. Yes, we’re using codec translation because our Asterisks connect SIP network to PSTN. We don’t use call recording. We tested on a dual-processor Xeon-3000MHz with SMP kernel, and with all the 240 calls running at the same time and in this case we have a CPU load of 30%. That’s why I’ve written about 60% with one CPU in my last post. In sip.conf we use ‘canreinvite=yes’. Please note that ‘reinvite=…’ is not correct! (voip-info.org/wiki/index.php … anreinvite)


#5

also not that reinvite is never used when you terminate to zaptel anyway. It is only used when doing sip to sip


#6

Nice, that answers my question nicely!

Then for another,
How easy was it to configure the channels?
As simple as auto-config?(Did i get the name right?)


#7

[quote=“mr_grr”]How easy was it to configure the channels?
As simple as auto-config?(Did i get the name right?)[/quote]

Well, If your telco provider gives you the proper settings for your PRI circuits, it’s a snap to setup 120 channels.


#8

Hi, just thought I’d ask how you got on with your Hotel install?
Did you end up using Telecom NZ or TelstraClear E1 - ISDN PRI circuits?
(If TelstraClear circuits are available, they are normally a little cheaper than Telecom NZ ones.)
From my reading of your posts, it seems that you didn’t need any channel banks - is that how it worked out for you?