This chapter discusses the cellular network interface and solution and presents a comprehensive discussion on the 5G enabling technologies. It introduces the concept of fiber‐wireless network convergence. The chapter also presents a broad explanation of the radio‐over‐fiber transmission scheme. It describes optical transport network multiplexing schemes and considers wireless based transport networks. The chapter then presents experimental channel measurement and characterization. It focuses on centralized/cloud RAN (C‐RAN) architectures due to their salient advantages such as cost‐effectiveness, efficient centralized processing, better service provisioning, support for dynamic resource allocation and mobile traffic load balancing. The chapter considers C‐RAN interfaces such as mobile backhaul (MBH) and mobile fronthaul (MFH). It also discusses the associated radio interface that can be employed for the in‐phase and quadrature data transmission between central units and distributed units. MBH/MFH transport network provisioning is largely based on optical fiber solutions.