Dialogic 6.2 Manuale Utente

Transferring Calls Using Release Link Trunk Transfer

November 2009

203

„

Set the switch type using the callctrl.cfg configuration file:

switch_type=nti_dms250

„

Set the transfer_variant using the callctrl.cfg configuration 

file, set:

transfer_Variant=rlt

„

Set the country code using the btcall.cfg configuration file:

country_code = 0010(US).

Country codes are listed in:

C:\Brooktrout\Boston\bfv.api\inc\ccode.h

Call transfer RLT functionality in BSMI is set in 

L4L3CALL_REQUEST:

rlt_service = 1

RLT is set with any non-zero value.

The destination number is set in L4L3CALL_REQUEST:

data.call_req_data.redirect_num.num_digits = 0;

RLT functionality in BSMI requires the D-channel set in 

L4L3mENABLE_PROTOCOL with:

‘switch_type’ = IISDNstDMS-250

and

‘variant’ =  IISDNvarNORTEL_CUSTOM

If the switch does not support RLT, an L3L4mALERTING message 

is received and the call is not transferred.

Applications with RLT release PRI-ISDN circuits after call transfer 

occurs, releasing corresponding circuits. A call comes through a 

B-channel, the caller requests a number and that call is transferred 

from one B-channel to the other B-channel. The calls are connected 

inside the public switch and remain active. The application tears 

down both B-channels and releases the link.

Calls without RLT are extended and subsequently bridged to a third 

party. The third party maintains the call and circuits are kept active 

and in service. This ties up additional circuits on the PRI trunk.