(Image copyright PizzaHut Malaysia, QSR Brands) Few days back, we dealt with a challenge to lock down phones in a callcenter of PizzaHut Malaysia. That was easy, we fired up a specialized context which I developed that uses Device User Mode based restriction. (If you wanna know more, about that, write me!). Now, we had a daunting task of getting the same kind of restrictions applied to user who perform transfers. By default, transfers are applied using the context “from-internal-xfer”. This is previously definable in FreePBX Advance settings, somehow it is now not available through the GUI. We had to make the same kind of restriction to those doing transfers too, so what we had to do, using Adminer (GUI database manager), look for a value in DB asterisk, table freepbx_settings called “from-internal-xfer”, for freepbx 2.10, look in asterisk DB, table, Globals, we changed that to “from-internal-xfer-phm”. Now, we forked the context out into our own little coding like here. Do note, after making changes in the DB, you need to make a change in the FreePBX gui, somewhere, and hit on the “Apply Config” button to materialize these changes. To verify, run # asterisk –rx “dialplan show globals” and it should show you “TRANSFER_CONTEXT=from-internal-xfer-phm” or whatever you’ve called it. Now that we are able to control transfers using our own context, we had to do it right and properly not to break other transfer functions with those whom are not bound by these restrictions. In this example below, I have agents in Device Usermode, logged in as a 6XXX extension. What we are required to do is to not allow transfers using phone (button transfer) or even Asterisk code *2. Now, with the phone we had to modify the Asterisk SIP Setting and add a value like below, in the other SIP Setting; allowtransfers=no That fixed the phone transfers, no one can use transfers using SIP invites anymore directly. Cool.! Now, we force users to use *2 instead and when that code is pressed, the calls are being thrown to context [from-internal-xfer-phm] In this context below, if any calls originating from 6XXX, retrieved from variable “PICKUPMARK” and is doing a transfer, looking at variable “TRANSFERNAME” which basically is populated when # transfers happen; we perform a soft hangup when those conditions are met, like below, otherwise, all others, we send back to the normal from-internal context, and basically allowing them to transfer it to wherever they like. , using this, you are free to write further more complex conditions as you please. [from-internal-xfer-phm]
exten => _[4-6]XXX,1,ExecIf($[“${PICKUPMARK:0:1}” = “6” & “${TRANSFERERNAME}” != “” ]?SoftHangup(Local/${EXTEN}))
exten => _X.,1,Goto(from-internal,${EXTEN},1)   Notes on the context above: 1) We catch calls in transfers made that start with digits 4 to 6, to digit “6” i.e. the call center agents. (We don’t want callcenter agents to call each other or in this case, transfer calls to each other) 2) It must be a transfer, i.e. must have the value TRANSFERNAME populated with something (With the two conditions above met, we do as below…, softhangup) 3) We softhangup the destination, i.e. EXTEN, causing the call to come back to the transferee   Have a good weekend folks!