 fronthaul transmission protocols have been studied since the inception of the C-RAN architecture. However, transport schemes such as CPRI have been predominantly considered for carrying raw I/Q samples in a traditional C-RAN architecture. Considering the potential for various functional splits between the BBU and the RRH, different types of information might need to be transported over the fronthaul link. Given the extensive adoption of Ethernet in the data centers and the core network, RoE could be a generic, cost-effective, off-the-shelf alternative for fronthaul transport. Furthermore, while a single fronthaul link per RRH to the BBU pool has usually been assumed, it is expected that the fronthaul network will evolve to more complex multi-hop topologies, requiring switching and aggregation. This is further facilitated by a standard Ethernet approach. Nevertheless, packetization over the fronthaul introduces some addi- tional concerns related to latency and overhead. As information arriving at the RRH and/or BBU needs to be encapsulated in an Ethernet frame, header-related overhead is introduced per frame. To ensure that this overhead is small, and does not waste the potential bandwidth gains from baseband functional splitting, it would be desirable to fill an Ethernet payload before sending a frame. However, waiting to fill a payload introduces additional latency. Hence, it is important to consider the impact of packetization on the fronthaul bandwidth 68 Chapter 1 and latency, in conjunction with possible functional splits between RRH and BBUs, in order to understand the feasibility and potential gains of different approaches. In the study item for the new radio access technology, 3GPP studied different functional splits between the CU and the DU [34]. Fig. 1.26 shows the possible functional splits between the CU and the DU. After months of discussions between the opponents and propo- nents of open interfaces, 3GPP initially decided to specify two out of eight possible func- tional splits, that is, options 2