Integrated Access and Backhaul (IAB)
Integrated Access and Backhaul is a 5G feature that lets a base station use the same radio spectrum both to serve users and to connect back to the network.
What is Integrated Access and Backhaul (IAB)?
Running fibre to every small cell is expensive. With IAB, a node relays its traffic by radio to a "donor" site that does have fibre, using 5G radio for the backhaul as well as for user access. This is especially useful for dense millimetre-wave deployments.