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New Member

PRI Connection to France Telecom

Please could you share any experience you have of connecting to the France Telecom telephone network. We are using a PRI 2621 router with an HDV/PRI card. The router is set up as switch-type primary-net5 and needed CRC-4 checking off before it would connect. We now have a connection, but calls do not connect reliably. Also the channels are assigned in "round-robin" rather than top-down or bottom-up order. I believe IOS 12.3 would allow us to match this - is anybody using this in production?

If anybody has any other suggestions I'd be very grateful!


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Cisco Employee

Re: PRI Connection to France Telecom

Hi David,

Can describe a bit more what you mean by "calls do not connect reliably"?

"isdn bchan-number-order {ascending | descending}" under d channel configuration determines in which order IOS uses B channels.

This command is available since 11.3T

You can check the following url for the command syntax:


New Member

Re: PRI Connection to France Telecom

Update : France Telecom today discovered that their switch was limiting the number of outgoing calls we could make.

Murat - thanks. The problem is that the FT switch does not do "bottom up" or "top down" channel assignment, which up to now have been the only two options. Their switch seems to do a "round-robin" and they are unable to change it. This is now an option with 12.3.


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