  We consider scalable cell-free massive multiple-input multiple-output
networks under an open radio access network paradigm comprising user equipments
(UEs), radio units (RUs), and decentralized processing units (DUs). UEs are
served by dynamically allocated user-centric clusters of RUs. The corresponding
cluster processors (implementing the physical layer for each user) are hosted
by the DUs as software-defined virtual network functions. Unlike the current
literature, mainly focused on the characterization of the user rates under
unrestricted fronthaul communication and computation, in this work we
explicitly take into account the fronthaul topology, the limited fronthaul
communication capacity, and computation constraints at the DUs. In particular,
we systematically address the new problem of joint fronthaul load balancing and
allocation of the computation resource. As a consequence of our new
optimization framework, we present representative numerical results
highlighting the existence of an optimal number of quantization bits in the
analog-to-digital conversion at the RUs.
