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PRI to PRI connectivity

Hi Guys,

I am looking for a solution wherein I want only two of my channels in the PRI link to connect to another PRI. At any time when a connection is made from RtrA to RtrB only two of the channels in the PRI line should be activated for this purpose. Any ideas.

Thanx in advance.



Re: PRI to PRI connectivity

Hi Hoogen ,

Configuring Channelized E1 ISDN PRI for two channels :

1. configure switch type using isdn switch-type switch-type

2.configure controller using controller e1 slot/port.

3.configure framing and linecode using framing crc4 & linecode hdb3

4.configure Pri group using pri-group [timeslots range] .

Note : If you do not specify the time slots, the specified controller is configured for 30 B channels and 1 D channel. The B channel numbers range 1 to 31; channel 16 is the D channel for E1. Corresponding serial interfaces numbers range 0 to 30. In commands, the D channel is interface serial controller-number:15. For example, interface serial 0:15.

Same is apllicable to Channelized T1 ISDN PRI



ex: pri-group timesolts 1-2 .


Re: PRI to PRI connectivity

You need to channelize your PRI as per Satish.


Re: PRI to PRI connectivity

I wouldn't want a permanent circuit, which like the channelized E1 would form. I need it to be dynamic and when i fires to that particular router it should fire only two channels. i could do a backup command after i configure the channelized E1 but any other solution?


Thanx for the replies

Re: PRI to PRI connectivity

Hi Hoogen,

Just a bit of value add to Satish's proposal.

Actually the difference here is the command Pr-Group instead of Channel-Group, and the moment you enter this command on an E1 card, it will automatically create associated the Serial Interfaces on the Router e.g. serial 0/0:1-31.

Howver all the ISDN Dialer Configuration MUST be configured only on the Serial 0/0:15 interface with Dialer Map as you would configure on any ISDN BRI implementation.

I guess I made it bit more clear to understand.

Please let us know if you need more info, meanwhile you may visit the URLs for info.


Please rate if it helps,

Kind Regards,

Wilson Samuel

Hall of Fame Super Gold

Re: PRI to PRI connectivity

Excuse me, but I think this is not what the question is about. Is not about reducing a fine 30-channel PRI to two.

What he wants is to limit bandwidth between these two particular sites to 128K, then perhaps do something else with the remaining 28 channels.

This is done with the command "dialer max-call " in interface configuration mode.

Hope this helps, please rate post if it does!


Re: PRI to PRI connectivity

Hi Paolo

That is exactly what I want to do. But I am not so sure about that command, I was looking at the dialer pool-member command

It kind of seems more appropriate.

For two links I might use this command

dialer pool-member 1 max-link 2

Do you think this is right?

Thanx for your help :)


Hall of Fame Super Gold

Re: PRI to PRI connectivity

Hi Hoogen,

Sometime in IOS there is more than one way to do the same thing and this can be your case.

I think, the difference is that "max-calls" limits the calls at dialer interface level, in theory these calls could be made over different physical interfaces. While "max-links" means, do not give more than two circuits to the pool-member, as you can have multiple pool members getting channels from a same physical interface.

In your case, as you have a single physical interface, the result should be the same.

Thanks for the nice rating and good luck!