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We evaluate the characteristics of each implementation, particularly for audio signals, and discuss the differences that arise between software and hardware implementations, along with the selection of an appropriate approach based on specific requirements. The evaluation results demonstrate that the software implementation of the CPFW framework has an overhead of 3.219\u2009ms, whereas the hardware implementation has an overhead of 310\u2009ns, indicating a difference in overhead of\n                    <jats:inline-formula content-type=\"math\/tex\">\n                      <jats:tex-math notation=\"LaTeX\" version=\"MathJax\">\\(10^{4}\\)<\/jats:tex-math>\n                    <\/jats:inline-formula>\n                    . The hardware implementation resulted in only a 5.88% increase in resource utilization owing to the addition of CPFW circuits, indicating that the added circuit size is practical for real-world applications.\n                  <\/jats:p>","DOI":"10.1145\/3777453","type":"journal-article","created":{"date-parts":[[2025,12,2]],"date-time":"2025-12-02T13:46:28Z","timestamp":1764683188000},"page":"1-27","update-policy":"https:\/\/doi.org\/10.1145\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Software and Hardware Implementations of a Cyber-Physical Firewall"],"prefix":"10.1145","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5766-0411","authenticated-orcid":false,"given":"Ryo","family":"Iijima","sequence":"first","affiliation":[{"name":"National Institute of Advanced Industrial Science and Technology, Koto-ku, Japan   and Waseda University, Shinjuku-ku, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9350-6091","authenticated-orcid":false,"given":"Tatsuya","family":"Takehisa","sequence":"additional","affiliation":[{"name":"National Institute of Information and Communications Technology, Koganei, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1583-4174","authenticated-orcid":false,"given":"Tatsuya","family":"Mori","sequence":"additional","affiliation":[{"name":"Computer Science and Communication Engineering, Waseda University, Shinjuku-ku, Japan, and National Institute of Information and Communications Technology, Riken AIP, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"320","published-online":{"date-parts":[[2026,1,20]]},"reference":[{"key":"e_1_3_2_2_2","first-page":"173","volume-title":"33nd International Conference on Machine Learning (ICML \u201916)","volume":"48","author":"Amodei Dario","year":"2016","unstructured":"Dario Amodei, Sundaram Ananthanarayanan, Rishita Anubhai, Jingliang Bai, Eric Battenberg, Carl Case, Jared Casper, Bryan Catanzaro, Qiang Cheng, Guoliang Chen et al. 2016. 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