Electronics are the technology of choice for most miniature communication networks (nanonetworks). However, chips are plagued by losses in signal transmission due to resistance (dissipation losses) as well as relatively low signal transmission speeds. Optical networks on the nano scale are limited in size by the wavelength of light. Plasmonic materials are man-made metamaterials that exploit coherent electron oscillations (surface plasmons (SPs)) at the interface between a metal and a dielectric. When the SPs couple with a photon, a surface plasmon polariton (SPP) is born. The SPP can propagate along the surface of the metal enabling a novel form of high-speed information transfer in nano-scale structures. In order to be useful in communications networks, their propagation must be controllable with switches. One potential way to control the plasmons is with a magnetic field. Scientists initiated the EU-funded project 'Theoretical study of molecular spin plasmonics for nanoscale communications' (TASMANIA) to investigate this potential. Researchers studied the optical properties and propagation of SPs in magnetic waveguides and cavities. This provided important insight into conditions leading to different types of propagation as well as electric and magnetic field distribution variations. Scientists demonstrated a switching effect as a result of electric field asymmetry. They also modified radiation from the cavity by tuning magnetisation of the waveguide, demonstrating the potential of magnetic control to switch field propagation. Plasmonics’ application in nano-scale communications’ networks offers high-speed data transmission with minimal loss in miniature devices in comparison to conventional electrical or optical technology. However, in order to be useful, the propagation of SPPs must be controllable with switches. TASMANIA provided theoretical and numerical evidence supporting the use of magnetic switches in controlling SPP propagation that will significantly improve the future of nano communication.