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New Member

how to block call from pstn

i have some problem about cost,here it is how users are using,

1. pstn A call to ipphone

2. ipphone transfer to pstn B

3. pstn A talk to pstn B ,here is it. why cost happen from calling ,IPPHONE system pay for? not pstn A or B


Re: how to block call from pstn

Basically your local phone service provider can not see what your CCM is doing with the call on the second transfer. To them it looks like a new call, thus you are getting charged for the second transfer, if there are any costs involved (i.e long distance).

Besides having a CCM, I also have a Nortel SL-100, on that PBX when you assign call transfer to a phone, you have the option of defining the call transfer capabilites as "call transfer all or call transfer intra-group, in other words restricted to the PBX". This is how we restrict most phones from transferring back off the PBX and incurring costs. Most users don't realize that if they receive a call from the PSTN, then in turn transfer the call back to the PSTN that they will incur the cost of the second if there is any associated costs. I don't believe CCM has the capabilities to restrict call transfer so what you have is a user training problem to make them aware of the danger of call transfers to long distance numbers.

New Member

Re: how to block call from pstn

thank you mcnerney, i user callmanager 4.2

. do you how to set callmanager to block this call scenario

Re: how to block call from pstn


You can block OffNet transfers with a CCM service parameter. Goto CCMAdmin->Service->Service Parameters->CallManager Service and adjust the below parameter to True. This is a global setting and will affect all calls to all phones that have a call marked as offnet. This might affect not just PSTN gateways if you have VOIP gateways with calls being marked as OFFNET vs. OnNET.

Block OffNet To OffNet Transfer : This parameter determines whether transfers between external (OffNet) parties are blocked (not allowed). Valid values specify True (block transfers between OffNet parties) or False (allow transfers between OffNet parties).

This is a required field.

Default: false.

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