  The emerging technology of quantum computing has the potential to change the
way how problems will be solved in the future. This work presents a centralized
network control algorithm executable on already existing quantum computer which
are based on the principle of quantum annealing like the D-Wave Advantage. We
introduce a resource reoccupation algorithm for traffic engineering in
wide-area networks. The proposed optimization algorithm changes traffic
steering and resource allocation in case of overloaded transceivers. Settings
of active components like fiber amplifiers and transceivers are not changed for
the reason of stability. This algorithm is beneficial in situations when the
network traffic is fluctuating in time scales of seconds or spontaneous bursts
occur. Further, we developed a discrete-time flow simulator to study the
algorithm's performance in wide-area networks. Our network simulator considers
backlog and loss modeling of buffered transmission lines. Concurring flows are
handled equally in case of a backlog.
  This work provides an ILP-based network configuring algorithm that is
applicable on quantum annealing computers. We showcase, that traffic losses can
be reduced significantly by a factor of 2 if a resource reoccupation algorithm
is applied in a network with bursty traffic. As resources are used more
efficiently by reoccupation in heavy load situations, overprovisioning of
networks can be reduced. Thus, this new form of network operation leads toward
a zero-margin network. We show that our newly introduced network simulator
enables analyses of short-time effects like buffering within fat-pipe networks.
As the calculation of network configurations in real-sized networks is
typically time-consuming, quantum computing can enable the proposed network
configuration algorithm for application in real-sized wide-area networks.
