Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. And see here for current known issues.

New Member

Trunk lines

Hi All ,

Just a quick one, i need to connect 32 Analog trunk lines to a PABX and 4 PRI's to the PSTN. any Suggestions on which Cards i could use on the ISR to achieve this

Thanks in Advance

Hall of Fame Super Gold

Re: Trunk lines


from the PBX point of view, trunk lines are FXO, that is, analog lines that normally go to the pstn. This means the voice gateway will need FXS ports.

If this is your requirement, be aware that the integration may suffer of problems, for example you will not be able to give DID to the PBX.

Anyway, considering the density, the minimum you can use is a 2821 with EVM-HD-8FXS/DID + 2 x EM-HDA-8FXS, 2 x VIC-4FXS, 2 x VWIC2-2T1E1, 1 x PVDM2-32.

Hope this helps, please rate post if it does!

Hall of Fame Super Gold

Re: Trunk lines

Woops a small (but expensive) correction. You will actually need 2 x PVDM2-64 for the above, because even if is is an hairpinned configuration, IOS will not let create the voice port if there is not at least 1 DSP resource for each. 23 x 4 + 32 = 124.

This can turn out to be quite an expensive solution for an (apparently) simple task.

Hall of Fame Super Red

Re: Trunk lines

Hi Paolo,

Nice catch on this one! This really goes to show that you think these scenarios through (I always knew you did) 5 points for your continued great work :)