Advertisement
If you have a new account but are having problems posting or verifying your account, please email us on hello@boards.ie for help. Thanks :)
Hello all! Please ensure that you are posting a new thread or question in the appropriate forum. The Feedback forum is overwhelmed with questions that are having to be moved elsewhere. If you need help to verify your account contact hello@boards.ie
Hi there,
There is an issue with role permissions that is being worked on at the moment.
If you are having trouble with access or permissions on regional forums please post here to get access: https://www.boards.ie/discussion/2058365403/you-do-not-have-permission-for-that#latest

Back to Backing BRI interfaces

  • 20-02-2007 5:18pm
    #1
    azzeretti
    Registered Users, Registered Users 2 Posts: 1,477 ✭✭✭


    Anyone know how to do this? I won't go into why this needs to be done, but the cheap-skating customer is looking for this!!
    Two 800 series back on 12.04. I can certainly do this with PRI interfaces but I am pretty sure (because of the nature of the BRI interfaces) that this is impossible.

    Anyone ever done it?


Comments

  • #2
    fatherdougalmag
    Registered Users, Registered Users 2 Posts: 1,391 ✭✭✭fatherdougalmag


    Yes it's possible. You need a cross-over cable with a resistor (100 ohm?). Furthermore you need to run of the interfaces in NT (network) mode (whilst the other remains in TE mode).


  • #3
    fatherdougalmag
    Registered Users, Registered Users 2 Posts: 1,391 ✭✭✭fatherdougalmag


    A bit more info on the resistor here. As far as I know, for shorter distances you use a 50ohm resistor.


  • #4
    azzeretti
    Registered Users, Registered Users 2 Posts: 1,477 ✭✭✭azzeretti


    Thanks for this, but I forgot to mention that there is no PBX in the middle. So the above method won't work.

    Any other ideas?


  • #5
    fatherdougalmag
    Registered Users, Registered Users 2 Posts: 1,391 ✭✭✭fatherdougalmag


    It will! I use BRI (and PRI) back to back every day! I actually have a regular 'straight' cable and then an adapter which incorporates the crossover and the resistor. A colleague here needed BRI back to back cables and made them up himself.

    In the link I posted, he wanted to plug an ISDN card (TE device) into his PBX (TE device) so he needed a crossover cable. Don't let the PBX thing put you off. He needs to connect two TE devices together directly. He also needed to run his ISDN card in NT mode so he had a TE talking to an NT. That's one part of the problem. He then goes on how to make the cable to connect the ISDN interfaces back to back by crossing over and applying resistors.


Advertisement