What is Hairpin call in context of voip?

Question

There are two termination

1) Physical
2) Ephemeral

For simple call.
So How many termination in CONTEXT for conference call ??

Answer 1

In VoIP, hairpin (or hairpining) is the means to send a call back in the direction that it came from. If a call cannot be routed over IP to a gateway that is closer to the target telephone, the call typically is sent back out the local zone the same way from which it came.