Call transfer

Toolpack software provides call transfer support, either by relaying call transfer requests and responses between two bridges call legs, or by locally processing the call transfer (making a new outgoing call leg, joining incoming call leg to the new outgoing call, dropping the original outgoing call leg).

Call transfer terms:

• Transferee: The incoming call leg, that is initially speaking with the Transferor, then later transferred to the Transfer Target.
• Transferor: The outgoing call leg that is initiating the call transfer request, and that gets disconnected once the transfer has been completed.
• Transfer Target: The second outgoing call leg, which is later made and joined to the Transferee

Supported call transfer protocols

• SS7: Not supported
• ISDN: Using Q.931 Facility IE
• CASR2: Not supported
• SIP: Using SIP Refer

Toolpack configuration

The Call transfer behavior is configured per profile. In the web portal:

• Click on Profiles in the left menu
• Select the profile to edit: the profile used on the Transferor call leg (outgoing call leg)
• Expand section 'Call Transfer Options'
• Choose appropriate options:
  • Call Transfer Mode: Indicates if call transfer requests from outgoing leg must be relayed to incoming leg, or locally processed
  • Terminate Transferor immediately: When checked, the Transferor all leg is immediately terminated when new outgoing call leg is made. Otherwise, it's terminated only once the Transfer Target answers, and may be re-joined later with Transferee if Transfer Target fails or times out.
  • Call Transfer timeout: Timeout waiting for Transfer Target to answer before declaring the call transfer as failed.