Home > Communication Service Provider Solutions > Enabling Telecom Transformation > RAN Pooling - The case for RAN pooling with Cloud/Virtualized RAN > Introduction
Early 2G and 3G traditional RAN deployments saw Radio Frequency (RF) cabling between the antennas on the tower to the base unit, which contained a Base Band Unit (BBU), and the Radio Unit (RU) hardware. Later 3G and 4G deployments saw the RU located at the base of the antenna tower mast, with RF fiber optic cabling between the RU and BBU over the Common Public Radio Interface (CPRI), as shown in Figure 1.
In these traditional deployments, which account for most RAN deployments in the world today, both the RU and BBU were built using Application-Specific Integrated Circuit (ASIC) hardware and software.
The virtualization and containerization of 5G RAN NFs as microservices running on COTS hardware, rather than on monolithic, proprietary purpose-built hardware, enables implementing and managing NFs as cloud-native applications (Figure 2). This is referred to as Cloud RAN (C-RAN). C-RAN changes the dynamics of RAN deployment, bringing unprecedented flexibility in deploying and scaling RAN architectures.