The gateway that terminates the interface toward Evolved UMTS Terrestrial Radio Access Network (E-UTRAN). S-GW is responsible for handovers with neighboring eNodeBs, as well as for data transfer of all packets across the user plane from the eNodeB to the P-GW. It is also the mobility anchor point for Inter-Radio Access Technology (RAT) handover between different generations of mobile networks such as 2G/3G.
Home S-GW (Serving Gateway)