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New Member

Ext. by ext. PSTN call blocking

Under CCM IPT deployment, is it possible to control (by CCM) that some users have DID while other users do not have (accept only internal call)?

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Re: Ext. by ext. PSTN call blocking

Hi Lawrence,

This is possible using CCM. What we do is the following;

DID Range ** xxx-240-60xx to xxx-240-69xx this is used for standard users.

Internal Incoming Access Range ** 27xx,28xx,29xx these 4-digit numbers can be called On Campus only and can call Off Campus, but cannot be called from the PSTN.

So just assign a pool of numbers outside your DID Range for this purpose. For Outgoing calling these DN's can be assigned any CSS etc.

Hope this helps!


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New Member

Re: Ext. by ext. PSTN call blocking


Sorry for belated response...

Actually, as my customer already having her private extensions assigned inside the DID range, so I am actually looking for something that can be configured extension by extension inside CCM...

Thanks and Regards,



Re: Ext. by ext. PSTN call blocking


It is possible, but depending on you setup can be quite complex.

One way is to ensure that your dial-peer configuration does not match the extensions you do not want to be reachable directly from the outside.

If the extensions are not in a range this means creating a lot of dial-peers :-(

Another way is that you add a prefix before the H.323 gateway forwards to CCM, then add translation patterns that match the extensions+prefix that should be reachable using DID to be translated so that the prefix is removed again. This is most likely the easiest way if you have a H.323 gateway and the extension are not in one range.

If you're using a MGCP gateway there are probably other possibilities using partitions and calling search spaces, but I am not familiar with MGCP gateway config, so I'm not able to tell nor verify.

I would go for option 2 :-)

Hope it helps,


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