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VeriSign® ISUP Trunk Signaling

Existing Customers EXTRAnet Applications

How It Works

1. Call request started from originating switch (SSP or MSC) to terminating switch.

2. “Initial Address” message sent from originating switch and STP to terminating STP and switch. Originating switch reserves a trunk between itself and terminating switch.

2. If called party is available, “Answer Complete” message is returned to originating switch. If not available, terminating switch responds with a busy tone and call ends.

3. Switch receives “Answer Complete” message, indicating availability and completed connection.

4. To end a call, the switch receiving a “Release” message releases its facility and transmits a “Release Complete” message to the switch that initiated the first release.

Need More Information?

Speak with a sales representative at: 
650-426-5310 or request information online.