T1 line to Communcation Manager Express

[valides007]

I have a Communcation Manager Express running on 2 routers (cisco 2951): one active and another standby for redundancy.

I contacted AT&T to get the T1 line for the WIC card and they get back to me with a form to be filled. I'm having some hard time to understand two of the questions they need answers for:

• ISSDN Version: National 1 or National 2

In CME i have ISDN switch configured as primary-ni. Is this national 1 or national 2?

• D-Channel Configuration: D Channel Per T, Shared D Channel for T1's or Shared D Channel + B/U.

Which one of the 3 should I pick? I need both routers to be on the T1 line. When the active router goes offline, the second will become active and all calls will be routed through the same T1.

[Brandon Svec]

Hi, you want ni2 and d channel per T1 otherwise known as package 1 or PRAS1 in att vernacular.

[paolo bevilacqua]

Brandon's da man, he even speaks telco lingo!

I can add the share D chans are know are NFAS. you do not want them with CME. Also having a T1 just redudncacy is largely usels. In the very unlikely event the router fails, just manually switch the circuit to the backup CME.