Any modern communications network is a complex architectural arrangement. By 2013 it’s likely that a mobile network operator will have 2G, 3G and LTE operations running in parallel, with support infrastructure such as backhaul that has been updated and augmented over the years. As networks mature, they also evolve—the trend right now is to alleviate RAN congestion with smaller cells, increasing network density but also putting extra burden on the backhaul infrastructure. In order to keep pace, backhaul implementations also need to evolve.