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T1 - Trunk Groups


Hi Group,

I'm involved in a scenario where I have a partial T1 dropping in 10 DS0 voice channels and my requirement is for me to be accepting incoming calls from the bottom and placing outgoing calls from the top.

How would I go about doing this? I'm looking at some documentation and the concept of using Trunk Groups appears to possibly be it...


paolo bevilacqua
Hall of Fame Master Hall of Fame Master
Hall of Fame Master

Is that PRI, or CAS that you have ?


The connection is a PRI.

PRI defaults to the anti-glare hunt scheme you described, so nothing needs to be done about.

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What about if it was a T1 CAS?

Same IIRC. But in that case, you would be able to use alternative using trunk-group.

So I shouldn't have to put in any additional configuration?

Do you know of any Cisco doc's that explain this?

No additional config. You can refer to "isdn bchan-number-order" command.

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So would this configuration be along the right track?

controller T1 0/3/0

clock source internal

pri-group timeslots 1-10

framing esf

linecode b8zs

It mentions having to set the 'isdn switch-type'. Im guessing this is a question I'd have to ask my TSP?

Any issues with the above configuration?

Clock source should be "line" (default).

All other commands except pri-group are default so do not need to be entered.

You will also need network-clock-participate and network-clock-select 1 T1 0/3/0

Beside switch-type, there are other fine tunings needed that you may or may not need.

Seem to me you have no intention of rating useful posts so I can only add "good luck" after this.

Sorry about that, I do apologize.

For isdn-switch type, is their a common type seen in the US? Or is this usually service provider dependent?

Nowadays is just an emulation setting by telco on their platform. Whatever you set makes no difference and will work even if mismatched.

Note: sorry too see that you cannot use the rating system in a fair manner, as you received a series of 100% complete and correct answers in the shortest timeframe possible, yet only average ratings have been left.

Whatever your expectations are, I'm clearly unable to meet them and will refrain to further answer questions from you in the future.

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