Question on configuring E1 Circuit

[ciscoroyzhang]

Hi there,   I have configured the E1 link as following

    Controller E1 0/0/0                        

     pri-group timeslots 1-10

and check the new S0/3/0:15 interface, it shows:

    interface Serial0/0/0:15

     isdn switch-type primary-net5

     isdn incoming-voice voice

question:  do I need issue the following command, since without them it still works fine?

     isdn bchan-number-order ascending

     isdn outgoing display-ie

Thanks

Roy

[ronpatel]

Hi Roy,

Without the above two commands also the PRi link will work. These are not mandatory configuration.

Regards

Ronak Patel

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[ciscoroyzhang]

Hi Ronak. thanks for the reply.   about the    isdn bchan-number-order ascending  I was told that by default the client site ISDN channel will be in desending mode and if it is in fructional, then we have to change it to acending so the call will not start to use the channel 30 which is not availble in isdn 10. but seem to me this is not corrrect.  thanks Roy

[Aaron Harrison]

Hi Roy

That is one solution to a fractional PRI - I have a lot of customers here in the UK using the same configuration, though it's not exactly what Cisco recommend it seems to work fine.

Aaron

[paolo bevilacqua]

That is one solution to a fractional PRI - I have a lot of customers here in the UK using the same configuration, though it's not exactly what Cisco recommend it seems to work fine.

The limitation only exists for MGCP. For all normal gateway-based protocols Cisco did not ever made statements on the matter, and supported any number of timeslots since day 1 (when voice PRI did not even existed).

[Aaron Harrison]

Hi Paolo

Erm.. yes. My mistake, I was in MGCP mode and was wrong even with regards to MGCP! It would be the channel selection order in CUCM that would be changed, as the command on the gateway would only affect H.323

oops.

Aaron

[paolo bevilacqua]

roy zhang wrote:
 Hi Ronak. thanks for the reply.   about the    isdn bchan-number-order ascending  I was told that by default the client site ISDN channel will be in desending mode and if it is in fructional, then we have to change it to acending so the call will not start to use the channel 30 which is not availble in isdn 10. but seem to me this is not corrrect.  thanks Roy

Router will place always outgoing calls starting from the highest free channel, so nce you configure timeslots 1-10 as in the example above, that will be channel 10.

Consequently, the default of 'descending' works fine and does not need to be changed.