Carrier ethernet for mobile backhaul [Guest editorial]

Mobile backhaul typically refers to the network between the base station site and the network controller site. However, mobile backhaul can also include a spectrum of networks and network technologies including the radio access network (RAN) and core networks. Network providers are faced with a number of significant challenges in delivering mobile backhaul solutions. As bandwidth demand increases to support new users and mobile applications, the need to invest heavily in new mobile backhaul infrastructure has to be carried out against a backdrop of (at best) modest revenue growth. This is further complicated by the need to support a wide variety of evolving mobile technologies (second generation (2G), 3G, and 4G), which adds complexity to migration strategies. Solutions based on timedivision multiplexing (TDM) will not be able to deliver the required cost point, which will necessitate improved efficiency and lower cost of bandwidth. This is driving an evolution toward Ethernet and IP-based backhaul solutions. However, in doing so, there are capabilities inherent to TDM that need to be developed in Ethernet, such as the requirements to support synchronization at cell sites.