Most of the calls we carry or generate consist of multiple call legs.
Whilst this detail is irrelevant for the most part, in order to fully understand our detailed CDRs (call data accessible via telecoms.calldata.detail.get) and call-webhooks, it is important to understand this concept.
For example, for an NTS call (where the caller dials one of our numbers and then we send that call back out to a different number, eg your mobile) will, in the simplest case, consist of two call legs. Leg 1 is the call coming in to us from the caller, and leg 2 is our system calling out to the destination number. These two call legs are then bridged together so that a conversation can proceed. Whilst this is a seamless experience for the caller and called party, under the hood, there are two call legs.
An NTS call which delivers to a huntgroup (routeplan - see telecoms.routeplan functions) may try one destination and, if unanswered after a set time, try a second destination. In this instance, as before leg 1 is the inbound call coming in to our system, the call attempt to the first destination will be leg 2 and the call attempt to the second destination will be leg 3.
A callback call would also typically have two call legs:
The distinction between call legs allows detailed status of each part of a call to be obtained, yet all sub-parts of a call to be easily associated with each other.