  The blockchain technology has achieved tremendous success in open
(permissionless) decentralized consensus by employing proof-of-work (PoW) or
its variants, whereby unauthorized nodes cannot gain disproportionate impact on
consensus beyond their computational power. However, PoW-based systems incur a
high delay and low throughput, making them ineffective in dealing with
real-time applications. On the other hand, byzantine fault-tolerant (BFT)
consensus algorithms with better delay and throughput performance have been
employed in closed (permissioned) settings to avoid Sybil attacks. In this
paper, we present Sybil-proof wirelEss Network coordinAte based byzanTine
consEnsus (SENATE), which is based on the conventional BFT consensus framework
yet works in open systems of wireless devices where faulty nodes may launch
Sybil attacks. As in a Senate in the legislature where the quota of senators
per state (district) is a constant irrespective with the population of the
state, "senators" in SENATE are selected from participating distributed nodes
based on their wireless network coordinates (WNC) with a fixed number of nodes
per district in the WNC space. Elected senators then participate in the
subsequent consensus reaching process and broadcast the result. Thereby, SENATE
is proof against Sybil attacks since pseudonyms of a faulty node are likely to
be adjacent in the WNC space and hence fail to be elected.
