Dial plan process
On the calling side
Figure 26 shows the dial plan operation process on the calling side.
Figure 26: Flow chart for dial plan operation process on the calling side
The voice gateway on the calling side replaces the calling and called numbers according to the number substitution rule on the receiving line.
The voice gateway performs global number substitution.
The gateway selects a proper voice entity based on the voice entity selection priority rules and replaces the calling and called numbers.
The gateway initiates a call to the called side and sends the calling and called numbers.
On the called side
Figure 27 shows the dial plan operation process on the called side.
Figure 27: Flow chart for dial plan operation process on the called side
After receiving a voice call (the called number), the voice gateway on the called side performs global calling/called number substitution.
The voice gateway on the called side selects proper voice entities based on the voice entity selection priority rules. (Number substitution might also be involved during the voice entity selection.) If the called party is a local voice subscriber, the gateway directly connects the subscriber line. If the called party is a PSTN subscriber, the gateway initiates a call and sends the calling and called numbers to the PSTN. The PBX in the PSTN connects the call.