LTTS_Week1 LTTS_4G & 5G LTE/NR RAN Engineering_Week1 The number of attempts remaining is 1 1 / 30 1. NG-C primarily connects which entities? a. gNB ↔ AMF b. eNB ↔ MME c. gNB ↔ UPF d. gNB ↔ neighboring gNB only 2 / 30 2. Which set contains only control-plane interfaces? a. S1-U, NG-U, X2-U b. S1-U, X2-C, NG-U c. S1-MME, NG-C, X2-C d. NG-U, S1-MME, X2-U 3 / 30 3. Which statement best distinguishes LTE from 5G NR? a. LTE mainly uses 15 kHz SCS, while NR supports multiple numerologies b. LTE uses only TDD c. LTE abandons OFDM d. LTE supports slicing while NR removes it 4 / 30 4. Which arrangement describes Option 6? a. RRC in CU, rest in DU b. PHY in CU, RF in DU c. PDCP in CU, RLC/MAC/PHY in DU d. MAC in CU, PHY/RF in DU 5 / 30 5. Which is the correct simplified LTE protocol stack from higher to lower layers? a. RRC → PDCP → RLC → MAC → PHY b. PDCP → RRC → MAC → RLC → PHY c. SDAP → RRC → RLC → PHY → MAC d. RRC → SDAP → PDCP → MAC → PHY 6 / 30 6. Which interface carries LTE control-plane signaling between eNB and MME? a. S1-U b. X2-U c. Xn-U d. S1-MME 7 / 30 7. RRC, SDAP and PDCP are centralized while RLC and MAC remain near the radio. What architecture is this? a. MME/S-GW split b. CU/DU split c. EPC split d. UE/eNB split 8 / 30 8. Which interface carries 5G user-plane traffic between NG-RAN and 5GC? a. E1-C b. F1-C c. NG-C d. NG-U 9 / 30 9. Which architecture is more suitable for full 5G capabilities such as native slicing and URLLC-oriented services? a. LTE FDD only b. SA with 5GC c. LTE-only EPC d. NSA Option 3 only 10 / 30 10. Which interface connects neighboring LTE eNBs for mobility coordination? a. S1 b. X2 c. F1 d. NG 11 / 30 11. Which function is primarily associated with the CU rather than the DU? a. PDCP b. Lower PHY c. RF amplification d. RF processing 12 / 30 12. Which statement best describes typical LTE-based NSA deployment? a. NR operates without LTE b. NR connects directly to 5GC c. LTE and NR use separate cores d. LTE/EPC acts as an anchor while NR enhances radio capability 13 / 30 13. In the provided functional split model, Option 2 places the boundary between: a. PHY/RF b. RRC/PDCP c. MAC/PHY d. PDCP/RLC 14 / 30 14. What distinguishes a split gNB from a monolithic gNB? a. Monolithic gNB requires EPC b. Selected gNB functions are separated between CU and DU c. Split gNB cannot use NR d. Split gNB has no PHY 15 / 30 15. Operator A has high-capacity, low-latency transport between CU and DU. Operator B has limited transport. What is the likely consequence? a. B should centralize PHY b. Transport does not matter c. Both must use identical splits d. A has more flexibility for centralized/deeper splits 16 / 30 16. Which 5GC function is correctly paired with its responsibility? a. UDM → radio scheduling b. SMF → session management c. UPF → subscriber database d. AMF → packet forwarding 17 / 30 17. Which comparison between EPC and 5GC is most accurate? a. PCRF and RLC are identical b. HSS and PHY are equivalent c. S-GW and UPF are associated with user-plane handling d. MME and AMF are packet forwarders 18 / 30 18. Which path correctly represents the LTE user-plane path toward an external packet network? a. UE → eNB → MME → HSS → Internet b. UE → eNB → PCRF → P-GW c. UE → eNB → S-GW → P-GW → external network d. UE → MME → eNB → S-GW 19 / 30 19. Which 5GC function primarily manages access and mobility? a. PCF b. AMF c. SMF d. UPF 20 / 30 20. Which architecture represents SA Option 2? a. LTE → EPC b. eNB → EPC → gNB c. NR → 5GC d. LTE → 5GC 21 / 30 21. What is the closest 5G counterpart to LTE X2 for inter-RAN-node communication? a. F1 b. S1 c. Xn d. E1 22 / 30 22. Which layer is not part of the basic LTE protocol stack described? a. RRC b. MAC c. SDAP d. PDCP 23 / 30 23. A UE moves from Cell A toward Cell B. Which combination is mainly required to maintain service continuity? a. Modulation + encryption b. Network slicing + UPF selection c. Frequency reuse + packet routing d. Mobility management + handover + RRM 24 / 30 24. A packet capture between LTE eNB and S-GW shows GTP-U. Which interface is being observed? a. X2-C b. S1-MME c. S1-C d. S1-U 25 / 30 25. Which comparison of base-station-to-core interfaces is correct? a. eNB–EPC = F1; gNB–5GC = E1 b. eNB–EPC = Xn; gNB–5GC = X2 c. eNB–EPC = NG; gNB–5GC = S1 d. eNB–EPC = S1; gNB–5GC = NG 26 / 30 26. Why is gNB functional splitting useful? a. It replaces RAN with MME b. It moves all functions into EPC c. It separates higher-layer and lower-layer processing d. It eliminates PHY 27 / 30 27. Which is the correct simplified NR protocol stack? a. RRC → PDCP → SDAP → PHY → RLC → MAC b. SDAP → RRC → PDCP → MAC → RLC → PHY c. RRC → MAC → RLC → SDAP → PDCP → PHY d. RRC → SDAP → PDCP → RLC → MAC → PHY 28 / 30 28. High-MAC is in CU and Low-MAC is in DU. Which split is this? a. Option 8 b. Option 2 c. Option 5 d. Option 4 29 / 30 29. Which NR layer maps QoS flows to Data Radio Bearers? a. SDAP b. PDCP c. MAC d. RLC 30 / 30 30. Which correctly separates SMF and UPF responsibilities? a. SMF handles RF; UPF handles RRC b. SMF forwards packets; UPF establishes identity c. SMF handles synchronization; UPF handles mobility d. SMF manages sessions; UPF handles user-plane packets Your score is
