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New Member

Cat5 for E1 ISDN PRI connection? Urgent :)


I have a customer that is running a 2911 with a VWIC2-2MFT-T1/E1 card. This is going to be connected to a ISDN E1 PRI from the public operator. The output from the PRI box is 120ohm.

My question is can I use a standard Cat5e cable for this connection? I know that the cat5 UTP cable is 100ohm and was wondering if that will cause a problem? The distance between the PRI box and the VWIC interface is about 8-9m.

I really need some help and hopefully asap  

Best regards


  • WAN Routing and Switching
New Member

Cat5 for E1 ISDN PRI connection? Urgent :)

At that distance you should be fine, although make sure to monitor the state of the SPAN for errors/drops in sync. 

New Member

Cat5 for E1 ISDN PRI connection? Urgent :)

Thanks. We have decided not to risk this as the customer is a large bank.......... Can anyone tell me if the CAB-E1-RJ45TE= is the correct cable to use from the vwic to the PRI box? 120 ohm and RJ to RJ.

Hall of Fame Super Gold

Cat5 for E1 ISDN PRI connection? Urgent :)

There is no risk. Any impedence cable will work, and often telco guys will make one free of charge. Just respect that pairs and pinout that is different from Ethernet.