Dialogic 6.2 Manuale Utente

Transferring Calls Using Release Link Trunk Transfer

November 2009

205

The call is transferred by the board, but it must maintain active call 

setup on both B-channels for the duration of the call.

ALERTING

<=== L4L3mALERTING (B1)

Now that B-channel #2 is set up, continue 

with normal call setup on B1, sending 

alerting and connect.

CONNECT

<=== L4L3mCONNECT (B1)

SETUP

===> L3L4mSETUP_IND (B1)

The host receives an incoming call on 

B-channel #1. From the 

IISDN_CALLED_PARTY info, the host 

application determines this call needs to be 

rerouted to an alternate branch office.

SETUP

<=== L4L3mCALL_REQUEST (B2) 

rtl_service = 1

The host initiates outbound call on B2, 

setting the rlt_service flag to ‘1’.

ALERTING

===> L3L4mALERTING (B2) 

includes 0x1c (FACILITY) IE with 

call_id.

The network sends an ALERTING message 

with the FACILITY info element containing 

the call ID for the second link.

CONNECT

===> L3L4mCONNECT (B2)

FACILITY

<=== L4L3mFACILITY_REQUEST The host initiates the transfer and release 

process by sending a FACILITY message. 

The call_ref and l4_ref parameters of the 

initial (B1) call sends a 

L4L3mFACILITY_REQUEST message, 

and the application populates the 

IISDN_CALL_ID field with the call_id 

information retrieved from the ALERTING 

message of the second call (B2).