Читать книгу Mobile Communications Systems Development - Rajib Taid - Страница 61

Consider the S1 logical interface between the eNodeB and the EPC (consisting of Serving Gateway (S‐GW), Mobility Management Entity (MME), and packet data network gateway (P‐GW)) in the case of the LTE/EPC network. Similarly, consider the NG logical interface between the Next Generation Radio Access Network (NG‐RAN)/gNB and the User Plane Function (UPF) in the case of the 5G network. Refer to Figure 3.3a and b.

Figure 3.3 (a) LTE S1 and 5G NG logical interface: user plane. (b) LTE S1 and 5G NG logical interface: control plane.

Figure 3.3 shows that the S1‐U and NG‐U or the S1‐AP and the NG‐AP have the same protocol stack over the IP transport network. Protocol layer classifications under user plane and control plane protocols are described later in Section 3.2.