LTE : What L-GW does ?

Question

I have one doubt over S5 interface. Interface between SGW and PGW in lte core known as S5 interface. Now I found again S5 interface between L-GW( which is co-located with HeNB ) and SGW of core network. Can someone please explain why this interface is required ?

Answer 1

L-GW is specified in TS 23.060 [29] and in TS 23.401 [30]. The Local IP Access (LIPA) is achieved using a L-GW colocated with the H(e)NB. The L-GW is connected to the Serving Gateway (S-GW) or to the SGSN via the SeGW.

Basically, it is a functionality that can colocate with the HeNB, which can provide EPC data offloading capability by routing data between 2 UEs in the same cell locally, instead of breaking out into the EPC.