  As research on building scalable quantum computers advances, it is important
to be able to certify their correctness. Due to the exponential hardness of
classically simulating quantum computation, straight-forward verification
through classical simulation fails. However, we can classically simulate small
scale quantum computations and hence we are able to test that devices behave as
expected in this domain. This constitutes the first step towards obtaining
confidence in the anticipated quantum-advantage when we extend to scales which
can no longer be simulated.
  Realistic devices have restrictions due to their architecture and limitations
due to physical imperfections and noise. Here we extend the usual ideal
simulations by considering those effects. We provide a general methodology for
constructing realistic simulations emulating the physical system which will
both provide a benchmark for realistic devices, and guide experimental research
in the quest for quantum-advantage.
  We exemplify our methodology by simulating a networked architecture and
corresponding noise-model; in particular that of the device developed in the
Networked Quantum Information Technologies Hub (NQIT). For our simulations we
use, with suitable modification, the classical simulator of of Bravyi and
Gosset. The specific problems considered belong to the class of Instantaneous
Quantum Polynomial-time (IQP) problems, a class believed to be hard for
classical computing devices, and to be a promising candidate for the first
demonstration of quantum-advantage. We first consider a subclass of IQP,
defined by Bermejo-Vega et al, involving two-dimensional dynamical quantum
simulators, before moving to more general instances of IQP, but which are still
restricted to the architecture of NQIT.
