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