User`s manual

SIP User's Manual 8. Telephony Capabilities
Version 5.0 223 December 2006
8.4 FXO Operating Modes
This section provides a description of the FXO operating modes and gateway
configurations for Tel-to-IP and IP-to-Tel calls.
8.4.1 IP-to-Telephone Calls
The FXO gateway provides the following FXO operating modes for IP-to-Tel calls:
 One-stage dialing
• Waiting for dial tone
• Time to wait before dialing
• Answer supervision
 Two-stage dialing
 Dialing time
• Disconnect supervision
• DID wink
8.4.1.1 One-Stage Dialing
One-stage dialing is when the FXO gateway receives an IP-to-Tel call, off-hooks the PBX
line connected to the telephone, and then immediately dials the destination telephone
number. In other words, the IP caller doesn't dial the PSTN number upon hearing a dial
tone.
Figure 8-1: Call Flow for One-Stage Dialing