2 PRI's with one D-Channel

[vanagon2tdi]

Right now we have two PRI's from the Telco with separate D-channels put into a group.

They are able to group the two and give me one D-channel on their side, but how do I set it up on my side?

Dave

[teodorgeorgiev]

Read about NFAS. However, as far as I know, not all of the ISDN protocols support NFAS. NI2 does. ETSI and QSIG - do not.

[electro22]

Hi Dave -

Doing NFAS on 2 PRIs will not gain you anything. NFAS shares a D channel among multiple PRIs but it also requires a backup D channel on another span. So since you only have two spans you will still have a D channel on each span.

Also, NFAS is not supported on every Cisco gateway. Specifically, the 6608s do not support NFAS.

-Jaret

[mparekh]

You can configure NFAS and save 1 B channel, but I would think that having a backup D channel would me more important than an extra B-channel.

Also NFAS is not supported on MGCP gateway. To configure NFAS the gateway will need to be H323.

Below is a link for more info on NFAS:

http://www.cisco.com/en/US/products/sw/iosswrel/ps5207/products_configuration_guide_chapter09186a008020ecee.html