  This paper addresses the coordinated scheduling problem in cloud-enabled
networks. Consider the downlink of a cloud-radio access network (C-RAN), where
the cloud is only responsible for the scheduling policy and the synchronization
of the transmit frames across the connected base-stations (BS). The transmitted
frame of every BS consists of several time/frequency blocks, called power-zones
(PZ), maintained at fixed transmit power. The paper considers the problem of
scheduling users to PZs and BSs in a coordinated fashion across the network, by
maximizing a network-wide utility under the practical constraint that each user
cannot be served by more than one base-station, but can be served by one or
more power-zone within each base-station frame. The paper solves the problem
using a graph theoretical approach by introducing the scheduling graph in which
each vertex represents an association of users, PZs and BSs. The problem is
formulated as a maximum weight clique, in which the weight of each vertex is
the benefit of the association represented by that vertex. The paper further
presents heuristic algorithms with low computational complexity. Simulation
results show the performance of the proposed algorithms and suggest that the
heuristics perform near optimal in low shadowing environments
