A Termination Customer Trunk Group provides a means to accept a call (Inbound “A” Call Leg) from a customer for delivery to the PSTN. The Termination Customer Trunk Group is used to authenticate the sender of the SIP messages based on IP Address and Port information or SIP Registration. The Termination Customer Trunk Group’s Routing Plan is used to determine which vendor to route the call to. The Termination Customer Trunk Group’s associated Rate Decks are used to determine the cost of the call.

General Information

The general Trunk Group information and settings defined on this page. All trunks within the Trunk Group inherit the settings configured within the Trunk Group. 

Limits / Options

Loop Detection

Loop Detection refers to the ability on the switch side to detect looping and block calls based on the same ANI to the same DNIS within a specified timeframe.

• If the system detects a loop it will block the call for the same amount of time that the Loop Timer is set to. 

• A CDR/SIP Reason “503 LOOP_BLOCKED” will be returned when a loop is detected.

• You will find the option that allows the time interval and repeat interval to be set in the Trunk Group settings on ingress traffic.

Example: If you set 60 seconds in the Loop Timer and 10 calls in the Loop Occurrence, the block will be set for that calling/called pair on the trunk group for 60 seconds. If the 11th call that comes in within the next 60 seconds would be blocked. If the timer is set at 30 seconds and your counter is set at 5, the system will accept 5 repetitive calls within 30 seconds but will block the 6th and subsequent calls.