Logo
ScienceStack
Table of Contents
Fetching ...
Sign In

An Efficient and Secure Arbitrary N-Party Quantum Key Agreement Protocol Using Bell States

Wen-Jie Liu, Yong Xu, Ching-Nung Yang, Pei-Pei Gao, Wen-Bin Yu

TL;DR

The paper addresses the need for efficient and secure multi‑party quantum key agreement by identifying limitations in prior SAP1/SAP2 schemes and Zhu's improvements, including privacy leaks, fairness issues, and flip attacks. It introduces an arbitrary $N$‑party QKA protocol that encodes two bits per Bell‑state using four Pauli operations ${I, Z, X, Y}$, employs decoy single photons for eavesdropping detection, and uses a post‑measurement mechanism to thwart collusion among dishonest participants. The proposed scheme enables each party to contribute to the final key $K$ with $K = \bigoplus_{j=1}^N K_j$, while preserving privacy (only the XOR of others' keys can be inferred) and fairness (no subset of participants can offset another). Efficiency improvements are demonstrated in the three‑party case, achieving about 8.33% versus 4.17% and 3.57% for comparable prior protocols, making the approach more practical for distributed quantum cryptographic tasks such as cloud storage. The work advances QKA by combining higher encoding density with robust security mechanisms and practical resource requirements.

Abstract

Two quantum key agreement protocols using Bell states and Bell measurement were recently proposed by Shukla et al.(Quantum Inf. Process. 13(11), 2391-2405, 2014). However, Zhu et al. pointed out that there are some security flaws and proposed an improved version (Quantum Inf. Process. 14(11), 4245-4254, 2015). In this study, we will show Zhu et al.'s improvement still exists some security problems, and its efficiency is not high enough. For solving these problems, we utilize four Pauli operations {I, Z, X, Y } to encode two bits instead of the original two operations {I,X} to encode one bit, and then propose an efficient and secure arbitrary N-party quantum key agreement protocol. In the protocol, the channel checking with decoy single photons is introduced to avoid the eavesdropper's flip attack, and a post-measurement mechanism is used to prevent against the collusion attack. The security analysis shows the present protocol can guarantee the correctness, security, privacy and fairness of quantum key agreement.

An Efficient and Secure Arbitrary N-Party Quantum Key Agreement Protocol Using Bell States

TL;DR

The paper addresses the need for efficient and secure multi‑party quantum key agreement by identifying limitations in prior SAP1/SAP2 schemes and Zhu's improvements, including privacy leaks, fairness issues, and flip attacks. It introduces an arbitrary ‑party QKA protocol that encodes two bits per Bell‑state using four Pauli operations , employs decoy single photons for eavesdropping detection, and uses a post‑measurement mechanism to thwart collusion among dishonest participants. The proposed scheme enables each party to contribute to the final key with , while preserving privacy (only the XOR of others' keys can be inferred) and fairness (no subset of participants can offset another). Efficiency improvements are demonstrated in the three‑party case, achieving about 8.33% versus 4.17% and 3.57% for comparable prior protocols, making the approach more practical for distributed quantum cryptographic tasks such as cloud storage. The work advances QKA by combining higher encoding density with robust security mechanisms and practical resource requirements.

Abstract

Two quantum key agreement protocols using Bell states and Bell measurement were recently proposed by Shukla et al.(Quantum Inf. Process. 13(11), 2391-2405, 2014). However, Zhu et al. pointed out that there are some security flaws and proposed an improved version (Quantum Inf. Process. 14(11), 4245-4254, 2015). In this study, we will show Zhu et al.'s improvement still exists some security problems, and its efficiency is not high enough. For solving these problems, we utilize four Pauli operations {I, Z, X, Y } to encode two bits instead of the original two operations {I,X} to encode one bit, and then propose an efficient and secure arbitrary N-party quantum key agreement protocol. In the protocol, the channel checking with decoy single photons is introduced to avoid the eavesdropper's flip attack, and a post-measurement mechanism is used to prevent against the collusion attack. The security analysis shows the present protocol can guarantee the correctness, security, privacy and fairness of quantum key agreement.
Paper Structure (9 sections, 3 equations, 5 figures, 3 tables)

This paper contains 9 sections, 3 equations, 5 figures, 3 tables.

Table of Contents

  1. Introduction
  2. Review of SAPs and Zhu et al.'s improvement
  3. Review of SAP1 and SAP2
  4. Review of Zhu et al.'s improvement
  5. Our efficient and secure $N$-party QKA protocol
  6. Security and efficiency analysis
  7. Security analysis
  8. Effiency analysis
  9. conclusion

Figures (5)

  • Figure 1: The process of Shukla's two-party QKA protocol(SAP1).
  • Figure 2: The process of Shukla's three-party QKA protocol starting from Alice(I), Bob(II), Charlie(III), respectively.
  • Figure 3: Schematic diagram of our $N$-party Quantum key agreement protocol
  • Figure 4: The process of two-party scenario for our QKA protocol. (I) Alice sends sequence ${q'_{1(1)}}$ to Bob, then Bob encodes his key by applying ${I/Z/X/Y}$ on each qubit in sequence ${q_{1(1)}}$, and Bob sends back sequence ${q'_{1(2)}}$ to Alice. (II) At the same time, Bob also sends sequence ${q'_{2(1)}}$ to Alice for encoding operations, and then receives sequence ${q'_{2(2)}}$ from Alice. After Alice and Bob both received sequences $q'_{1(2)}$, $q'_{2(2)}$ from each other, they separately perform the Bell measurement and obtain each other's key.
  • Figure 5: The process of three-party scenario for our QKA protocol. Here (I),(II),(III) represent the corresponding round beginning from the sender Alice, Bob and Charlie, respectively. The detailed procedures of each round are similar to the two-party scenario.