  The violation of certain Bell inequalities allows for device-independent
information processing secure against non-signalling eavesdroppers. However,
this only holds for the Bell network, in which two or more agents perform local
measurements on a single shared source of entanglement. To overcome the
practical constraint that entangled systems can only be transmitted over
relatively short distances, large-scale multi-source networks have been
employed. Do there exist analogues of Bell inequalities for such networks,
whose violation is a resource for device-independence? In this paper, the
violation of recently derived polynomial Bell inequalities will be shown to
allow for device-independence on multi-source networks, secure against
non-signalling eavesdroppers.
