{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,27]],"date-time":"2026-03-27T15:16:07Z","timestamp":1774624567136,"version":"3.50.1"},"reference-count":30,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2025,6,5]],"date-time":"2025-06-05T00:00:00Z","timestamp":1749081600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Princess Nourah Bint Abdulrahman University Researchers","award":["PNURSP2025R500"],"award-info":[{"award-number":["PNURSP2025R500"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>Current improvements in quantum computing present a substantial challenge to classical cryptographic systems, which typically rely on problems that can be solved in polynomial time using quantum algorithms. Consequently, post-quantum cryptography (PQC) has emerged as a promising solution to emerging quantum-based cryptographic challenges. The greatest threat is public-key cryptosystems, which are primarily responsible for key exchanges. In PQC, key encapsulation mechanisms (KEMs) are crucial for securing key exchange protocols, particularly in Internet communication, virtual private networks (VPNs), and secure messaging applications. CRYSTALS-Kyber and NTRU are two well-known PQC KEMs offering robust security in the quantum world. However, even when quantum computers are functional, they are not easily accessible. IoT devices will not be able to utilize them directly, so there will still be a requirement to protect IoT devices from quantum attacks. Concerns such as limited computational power, energy efficiency, and memory constraints in devices such as those used in IoTs, embedded systems, and smart cards limit the use of these techniques in constrained environments. These concerns always arise there. To address this issue, this study conducts a broad comparative analysis of Kyber and NTRU, with special focus on their security, performance, and implementation efficiency in such environments (IOT\/constrained environments). In addition, a case study was conducted by applying KEMs to a low-power embedded device to analyze their performance in real-world scenarios. These results offer an important comparison for cyber security engineers and cryptographers who are involved in integrating post-quantum cryptography into resource-constrained devices.<\/jats:p>","DOI":"10.3390\/sym17060881","type":"journal-article","created":{"date-parts":[[2025,6,5]],"date-time":"2025-06-05T05:49:22Z","timestamp":1749102562000},"page":"881","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Post-Quantum KEMs for IoT: A Study of Kyber and NTRU"],"prefix":"10.3390","volume":"17","author":[{"given":"M. Awais","family":"Ehsan","sequence":"first","affiliation":[{"name":"School of Natural Sciences, National University Science Technology, Islamabad 44000, Pakistan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9968-8439","authenticated-orcid":false,"given":"Walaa","family":"Alayed","sequence":"additional","affiliation":[{"name":"Department of Information Technology, College of Computer and Information Sciences, Princess Nourah bint Abdulrahman University, P.O. Box 84428, Riyadh 11671, Saudi Arabia"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-6453-0664","authenticated-orcid":false,"given":"Amad Ur","family":"Rehman","sequence":"additional","affiliation":[{"name":"Department of Mathematics & Statistics, FOS, International Islamic University Islamabad, H-10, Islamabad 44000, Pakistan"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-4929-3316","authenticated-orcid":false,"given":"Waqar ul","family":"Hassan","sequence":"additional","affiliation":[{"name":"Department of Mathematics, Government College University, Lahore 54000, Pakistan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2641-1575","authenticated-orcid":false,"given":"Ahmed","family":"Zeeshan","sequence":"additional","affiliation":[{"name":"Department of Mathematics & Statistics, FOS, International Islamic University Islamabad, H-10, Islamabad 44000, Pakistan"},{"name":"Department of Mathematics, College of Science, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, Republic of Korea"}]}],"member":"1968","published-online":{"date-parts":[[2025,6,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"8","DOI":"10.1016\/S1361-3723(17)30051-9","article-title":"The impact of quantum computing on cryptography","volume":"2017","author":"Aumasson","year":"2017","journal-title":"Comput. 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