{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,14]],"date-time":"2026-02-14T20:52:44Z","timestamp":1771102364354,"version":"3.50.1"},"reference-count":27,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2024,12,4]],"date-time":"2024-12-04T00:00:00Z","timestamp":1733270400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Natural Science Foundation of China","award":["62162039"],"award-info":[{"award-number":["62162039"]}]},{"name":"National Natural Science Foundation of China","award":["61762060"],"award-info":[{"award-number":["61762060"]}]},{"name":"National Natural Science Foundation of China","award":["23YFGA0060"],"award-info":[{"award-number":["23YFGA0060"]}]},{"name":"National Natural Science Foundation of China","award":["23JRRA837"],"award-info":[{"award-number":["23JRRA837"]}]},{"name":"National Natural Science Foundation of China","award":["24YFFA016"],"award-info":[{"award-number":["24YFFA016"]}]},{"name":"Natural Science Foundation of Gansu Province, China","award":["62162039"],"award-info":[{"award-number":["62162039"]}]},{"name":"Natural Science Foundation of Gansu Province, China","award":["61762060"],"award-info":[{"award-number":["61762060"]}]},{"name":"Natural Science Foundation of Gansu Province, China","award":["23YFGA0060"],"award-info":[{"award-number":["23YFGA0060"]}]},{"name":"Natural Science Foundation of Gansu Province, China","award":["23JRRA837"],"award-info":[{"award-number":["23JRRA837"]}]},{"name":"Natural Science Foundation of Gansu Province, China","award":["24YFFA016"],"award-info":[{"award-number":["24YFFA016"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>The NC-Link protocol, as an integrated communication protocol in the Computerized Numerical Control (CNC) machine tool industry, has drawn significant attention regarding its security since its inception. Although there have been studies proposing improvements to address security issues related to key management and message transmission, systematic security analysis of the protocol remains relatively weak. To better investigate and enhance the security of the NC-Link protocol, our research introduces a formal modeling and analysis method based on Colored Petri Nets (CPN). By establishing a CPN model of the protocol, we analyze the security issues present during communication and propose improvement measures for verification and analysis. First, we developed a CPN model for the NC-Link protocol and verified the model\u2019s feasibility through simulation analysis. Subsequently, we introduced an attacker model to analyze the protocol\u2019s authentication interaction process, revealing security issues, such as authentication vulnerabilities and key management flaws. Finally, we proposed an improved scheme addressing these issues and conducted a security validation and cost analysis of this scheme. The results show that the improved protocol reduces the computational overhead by 75% during the connection and interaction phases. This indicates that the improved protocol can achieve interactions at a faster speed while maintaining higher security and reliability. The implementation of this scheme provides new reference ideas for related research.<\/jats:p>","DOI":"10.3390\/sym16121612","type":"journal-article","created":{"date-parts":[[2024,12,5]],"date-time":"2024-12-05T04:13:03Z","timestamp":1733371983000},"page":"1612","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Research on the Security of NC-Link Numerical Control Equipment Protocol Based on Colored Petri Net"],"prefix":"10.3390","volume":"16","author":[{"given":"Jianming","family":"Shi","sequence":"first","affiliation":[{"name":"School of Computer and Communication, Lanzhou University of Technology, Lanzhou 730050, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1611-9017","authenticated-orcid":false,"given":"Tao","family":"Feng","sequence":"additional","affiliation":[{"name":"School of Computer and Communication, Lanzhou University of Technology, Lanzhou 730050, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5283-6668","authenticated-orcid":false,"given":"Lu","family":"Zheng","sequence":"additional","affiliation":[{"name":"School of Computer and Communication, Lanzhou University of Technology, Lanzhou 730050, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yi","family":"Wu","sequence":"additional","affiliation":[{"name":"School of Computer and Communication, Lanzhou University of Technology, Lanzhou 730050, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,12,4]]},"reference":[{"key":"ref_1","first-page":"52","article-title":"Quantitative security risk assessment for industrial control systems: Research opportunities and challenges","volume":"9","author":"Eckhart","year":"2019","journal-title":"J. Internet Serv. Inf. Secur. (JISIS)"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Drias, Z., Serhrouchni, A., and Vogel, O. (2015, January 5\u20137). Analysis of cyber security for industrial control systems. Proceedings of the 2015 International Conference on Cyber Security of Smart Cities, Industrial Control System and Communications (SSIC), Shanghai, China.","DOI":"10.1109\/SSIC.2015.7245330"},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Martinov, G., Pushkov, R., and Evstafieva, S. (2022, January 4\u201310). Collecting Data from Variable Kinematic Machine Tools with OPC UA Protocol. Proceedings of the 2022 International Russian Automation Conference (RusAutoCon), Sochi, Russian Federation.","DOI":"10.1109\/RusAutoCon54946.2022.9896291"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"176","DOI":"10.1016\/j.jmsy.2021.05.010","article-title":"A digital-twin visualized architecture for Flexible Manufacturing System","volume":"60","author":"Fan","year":"2021","journal-title":"J. Manuf. Syst."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"2","DOI":"10.1109\/COMST.2002.5341329","article-title":"Formal methods for specification and analysis of communication protocols","volume":"4","author":"Babich","year":"2002","journal-title":"IEEE Commun. Surv. Tutor."},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Rocchetto, M., and Tippenhauer, N.O. (2016, January 14\u201318). CPDY: Extending the Dolev-Yao attacker with physical-layer interactions. Proceedings of the 18th International Conference on Formal Engineering Methods and Software Engineering (ICFEM 2016), Tokyo, Japan.","DOI":"10.1007\/978-3-319-47846-3_12"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"92","DOI":"10.1016\/j.procir.2014.07.148","article-title":"Machine monitoring system based on MTConnect technology","volume":"22","author":"Edrington","year":"2014","journal-title":"Procedia CIRP"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"61","DOI":"10.1016\/j.jmsy.2019.04.006","article-title":"A cyber-physical machine tools platform using OPC UA and MTConnect","volume":"51","author":"Liu","year":"2019","journal-title":"J. Manuf. Syst."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"915","DOI":"10.1016\/j.mfglet.2023.08.010","article-title":"Interoperable system for automated extraction and identification of machine control data in brownfield production","volume":"35","author":"Mattes","year":"2023","journal-title":"Manuf. Lett."},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Kwon, H., Kim, Y., Yoon, H., and Choi, D. (2017). Optimal Cluster Expansion-Based Intrusion Tolerant System to Prevent Denial of Service Attacks. Appl. Sci., 7.","DOI":"10.3390\/app7111186"},{"key":"ref_11","first-page":"86","article-title":"NC-Link: A Communication Protocol for Interconnected CNC Machine Tools in Intelligent Manufacturing","volume":"37","author":"Chen","year":"2024","journal-title":"Met. Process. (Cold Process.)"},{"key":"ref_12","first-page":"39","article-title":"Modeling Method for CNC Equipment Information Models Based on Knowledge Graphs","volume":"50","author":"Lu","year":"2022","journal-title":"J. Huazhong Univ. Sci. Technol. (Nat. Sci. Ed.)"},{"key":"ref_13","unstructured":"Li, Y. (2023). Design and Implementation of an NC-Link Access Control Scheme Based on Symmetric Homomorphic Encryption. [Master\u2019s Thesis, Huazhong University of Science and Technology]."},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Dong, Z., Qin, Y., Li, Z., and Wang, H. (2022, January 25\u201327). A Security and Trust Protection Framework for Open CNC Production Line. Proceedings of the 2022 China Automation Congress (CAC), Xiamen, China.","DOI":"10.1109\/CAC57257.2022.10055607"},{"key":"ref_15","first-page":"71","article-title":"An Effective Automated Detection System for Multi-Protocol Attacks","volume":"35","author":"Yang","year":"2012","journal-title":"J. Chongqing Univ. Nat. Sci. Ed."},{"key":"ref_16","first-page":"1740","article-title":"Research Progress on Security Protocols over the Past 20 Years","volume":"14","author":"Qing","year":"2003","journal-title":"J. Softw."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"198","DOI":"10.1109\/TIT.1983.1056650","article-title":"On the security of public key protocols","volume":"29","author":"Delov","year":"1983","journal-title":"Inf. Theory IEEE Trans."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"943","DOI":"10.1109\/TCST.2006.876921","article-title":"Formal verification of statecharts using finite-state model checkers","volume":"14","author":"Zhao","year":"2006","journal-title":"IEEE Trans. Control. Syst. Technol."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"503","DOI":"10.1504\/IJES.2018.095754","article-title":"Petri net-based verification of security protocol implementation in software evolution","volume":"10","author":"Ahmadon","year":"2018","journal-title":"Int. J. Embed. Syst."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"902","DOI":"10.3724\/SP.J.1146.2010.00751","article-title":"Research on a Modular Model Checking Method Based on SPIN","volume":"33","author":"Li","year":"2011","journal-title":"J. Electron. Inf. Technol."},{"key":"ref_21","first-page":"802","article-title":"Model Checking Method for Multi-Agent Interaction Strategy","volume":"45","author":"Zhang","year":"2016","journal-title":"J. Electron. Sci. Technol. Univ."},{"key":"ref_22","first-page":"716","article-title":"Security Analysis of Semi-Quantum Cryptographic Protocol Based on Model Checking","volume":"46","author":"Yang","year":"2017","journal-title":"J. Electron. Sci. Technol. Univ."},{"key":"ref_23","first-page":"240","article-title":"Formal modeling and security analysis method of security protocol based on CPN","volume":"42","author":"Gong","year":"2021","journal-title":"Tongxin Xuebao\/J. Commun."},{"key":"ref_24","unstructured":"Cervesato, I. (2001, January 16\u201319). The Dolev-Yao intruder is the most powerful attacker. Proceedings of the 16th Annual Symposium on Logic in Computer Science\u2014LICS, Boston, MA, USA."},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Ram, S.B., and Odelu, V. (2022, January 26\u201329). Security analysis of a key exchange protocol under dolev-yao threat model using tamarin prover. Proceedings of the 2022 IEEE 12th Annual Computing and Communication Workshop and Conference (CCWC), Virtual.","DOI":"10.1109\/CCWC54503.2022.9720852"},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Zheng, L., and Feng, T. (2022). Research on a vehicle authentication and key transmission protocol based on CPN. Symmetry, 14.","DOI":"10.3390\/sym14112398"},{"key":"ref_27","doi-asserted-by":"crossref","unstructured":"Du, J., Tang, R., and Feng, T. (2022). Security analysis and improvement of vehicle Ethernet SOME\/IP protocol. Sensors, 22.","DOI":"10.3390\/s22186792"}],"container-title":["Symmetry"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2073-8994\/16\/12\/1612\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T16:47:06Z","timestamp":1760114826000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2073-8994\/16\/12\/1612"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,12,4]]},"references-count":27,"journal-issue":{"issue":"12","published-online":{"date-parts":[[2024,12]]}},"alternative-id":["sym16121612"],"URL":"https:\/\/doi.org\/10.3390\/sym16121612","relation":{},"ISSN":["2073-8994"],"issn-type":[{"value":"2073-8994","type":"electronic"}],"subject":[],"published":{"date-parts":[[2024,12,4]]}}}