In this lab you will build a complete NSA Option 3x topology by placing the EPC core nodes including the MME, Serving Gateway, and PDN Gateway alongside the LTE eNB master node and the NR gNB secondary node. You will connect each element with the correct interfaces. The eNB connects to the MME via S1-MME for control signaling and to the SGW via S1-U for user plane. The X2 interface links the eNB and gNB for dual connectivity coordination. In the Option 3x variant most user plane data flows through the gNB directly to the SGW.