Continuous Variable Solution for Byzantine Agreement

We demonstrate that the Byzantine Agreement Problem (BAP) in its weaker version with detectable broadcast, can be solved using continuous variables Gaussian states with Gaussian operations. The protocol uses genuine tripartite symmetric entanglement, but differs from protocols proposed for qutrits or qubits. Contrary to the quantum key distribution (QKD) which is possible with all Gaussian states, for the BAP entanglement is needed, but not all tripartite entangled symmetric states can be used to solve the problem.