Orthogonal-state-based protocols of quantum key agreement

TL;DR

This paper introduces two new quantum key agreement protocols based on orthogonal states, one for two-party and one for multi-party scenarios, with security rooted in entanglement monogamy, differing from traditional non-orthogonal state methods.

Contribution

The paper presents novel orthogonal-state-based QKA protocols for two-party and multi-party systems, expanding the security foundation beyond non-orthogonal state principles.

Findings

Protocols are secure due to monogamy of entanglement

Existing quantum systems for dialogue can be adapted for QKA

Protocols are applicable to secure direct quantum communication

Abstract

Two orthogonal-state-based protocols of quantum key agreement (QKA) are proposed. The first protocol of QKA proposed here is designed for two-party QKA, whereas the second protocol is designed for multi-party QKA. Security of these orthogonal-state-based protocols arise from monogamy of entanglement. This is in contrast to the existing protocols of QKA where security arises from the use of non-orthogonal state (non-commutativity principle). Further, it is shown that all the quantum systems that are useful for implementation of quantum dialogue and most of the protocols of secure direct quantum communication can be modified to implement protocols of QKA.