Question: What is a primary objective of the X2 interface specification in E-UTRAN, as it relates to the inter-connection of base stations?
Option 1: To mandate a single, universal transport network protocol across all manufacturers.
Option 2: To enable seamless inter-connection between eNBs (eNodeBs) from different manufacturers and with en-gNBs in multi-connectivity scenarios.
Option 3: To consolidate Radio Network and Transport Network functionalities for simplified management.
Option 4: To restrict the use of X2 interface for only intra-manufacturer eNB communications.
Explanation: The correct answer, Option 2, reflects the objective of ensuring interoperability and seamless connectivity between base stations (eNBs) from various manufacturers, as well as their integration with en-gNBs in the context of E-UTRA-NR Dual Connectivity (EN-DC). This facilitates a heterogeneous network environment, promoting competition and innovation among manufacturers while ensuring cohesive network operation.