One of the major things not really addressed in the article is backhaul for each 4.5G&#x2F;5G cell site or small cell site. More air spectrum and better radio modulation&#x2F;MIMO for the cell-to-handset is very important, but that&#x27;s only a piece of the puzzle...<p>There&#x27;s still a lot of locations out there without fiber, or that are currently fed by a 250-400Mbps capacity PTP microwave link. Cellular carriers are aggressively spending money to bring dark fiber to tower sites, of course, with the minimum connectivity for a new site being a single 10GbE circuit. This is one of the things driving the growth of outside-plant fiber construction and dedicated-purpose dark fiber network operators (example: Zayo&#x27;s ongoing new builds spending $$$$$ in major metro areas in Texas).<p>The other part of the puzzle is much higher capacity new PTP microwave to feed sites, some of which will be logically downstream of newly fiber-fed sites. These new links will be at 1 Gbps to 5Gbps+ capacity.