We present a graph-based model for multiple scattering of light in integrated
lithium niobate on insulator (LNOI) networks, which describes an open network
of single-mode integrated waveguides with tunable scattering at the network
nodes. We first validate the model at small scale with experimental LNOI
resonator devices and show consistent agreement between simulated and measured
spectral data. Then, the model is used to demonstrate a novel platform for
on-chip multiple scattering in large-scale optical networks up to few hundred
nodes, with tunable scattering behaviour and tailored disorder. Combining our
simple graph-based model with material properties of LNOI, this platform
creates new opportunities to control randomness in large optical networks