  The security of quantum key distribution protocols hinges upon features of
physical systems that are uniquely quantum in nature. We explore the role of
quantumness as qualified by quantum contextuality, in quantum key distribution
schemes. We present a new quantum key distribution protocol whose security
depends uponthe KCBS inequality and contextuality monogamy. We explicitly
calculate the key rate, error rate introduced between Alice-Bob communication
due to the presence of Eve, and the information-gain by Eve. This protocol
provides a new framework for quantum key distribution which has conceptual and
practical advantages over other quantum protocols.
