Local Call Local Switch

In the classic 3GPP architecture, all calls go from BTS to BSC to MSC, only then to go back all the same way in case the second call leg is also in the same cell. Particularly in case of statellite or other expensive/slow back-haul this is far from ideal.

Using LCLS, a BSC can know which of the two call legs belong to one call, and can then directly bridge the RTP/media locally.

Spec references