  Millimeter wave (mmWave) communications has been recently standardized for
use in the fifth generation (5G) of cellular networks, fulfilling the promise
of multi-gigabit mobile throughput of current and future mobile radio network
generations. In this context, the network densification required to overcome
the difficult mmWave propagation will result in increased deployment costs.
Integrated Access and Backhaul (IAB) has been proposed as an effective mean of
reducing densification costs by deploying a wireless mesh network of base
stations, where backhaul and access transmissions share the same radio
technology. However, IAB requires sophisticated control mechanisms to operate
efficiently and address the increased complexity. The Open Radio Access Network
(RAN) paradigm represents the ideal enabler of RAN intelligent control, but its
current specifications are not compatible with IAB. In this work, we discuss
the challenges of integrating IAB into the Open RAN ecosystem, detailing the
required architectural extensions that will enable dynamic control of 5G IAB
networks. We implement the proposed integrated architecture into the first
publicly-available Open-RAN-enabled experimental framework, which allows
prototyping and testing Open-RAN-based solutions over end-to-end 5G IAB
networks. Finally, we validate the framework with both ideal and realistic
deployment scenarios exploiting the large-scale testing capabilities of
publicly available experimental platforms
