<![CDATA[Keamanan jaringan dan efisiensi penggunaan bandwidth merupakan faktor kunci bagi perusahaan yang bergantung pada internet untuk operasional harian. CV. Peut Sagoe Design, sebuah perusahaan arsitektur dan rekayasa teknik, menghadapi masalah pemborosan bandwidth akibat akses non-produktif serta risiko keamanan karena kurangnya kontrol lalu lintas data. Penelitian ini bertujuan untuk menganalisis efektivitas penerapan proxy server dalam meningkatkan keamanan jaringan dan mengoptimalkan penggunaan bandwidth. Metode penelitian terapan dengan pendekatan kuantitatif digunakan, melibatkan observasi, wawancara dengan 10 karyawan dan 2 staf IT, serta pengukuran parameter jaringan menggunakan PRTG Network Monitor dan Wireshark. Implementasi dilakukan dengan Squid Proxy pada Ubuntu Server 22.04, dikonfigurasi dengan caching, filtering, dan access control list (ACL). Data dikumpulkan sebelum dan sesudah implementasi untuk membandingkan rata-rata penggunaan bandwidth, kecepatan unduh/unggah, dan latensi. Hasil menunjukkan penurunan penggunaan bandwidth sebesar 42%, peningkatan kecepatan unduh sebesar 38,8%, penurunan latensi sebesar 47,7%, dan peningkatan stabilitas jaringan. Uji statistik paired t-test menghasilkan nilai p = 0,003 (< 0,05), menunjukkan perbedaan signifikan sebelum dan sesudah implementasi. Wawancara mengungkapkan akses cloud yang lebih cepat, waktu unggah/unduh yang lebih singkat, dan berkurangnya distraksi kerja akibat pembatasan akses. Penerapan proxy server terbukti efektif dalam meningkatkan efisiensi jaringan, keamanan data, dan produktivitas kerja. Keywords: proxy server, network security, bandwidth optimization, squid, computer network -------------------------------------------------------------------------------------------------- Optimizing Security and Bandwidth Usage on Internet Networks Using a Proxy Server at CV. Peut Sagoe Design Network security and efficient bandwidth usage are crucial factors for companies that rely on the internet for daily operations. CV. Peut Sagoe Design, an architecture and engineering firm, faces bandwidth wastage due to unproductive access and security risks due to lack of data traffic control. This study aims to analyze the effectiveness of implementing a proxy server in improving network security and optimizing bandwidth usage. The study uses an applied method with a quantitative approach, involving observation, interviews with 10 employees and 2 IT staff, and network parameter measurements using PRTG Network Monitor and Wireshark. Implementation was carried out using Squid Proxy on Ubuntu Server 22.04 configured with caching, filtering, and access control lists (ACLs). Data before and after implementation were compared to assess changes in average bandwidth usage, download/upload speeds, and latency. The results show a 42% decrease in bandwidth usage, a 38.8% increase in download speed, a 47.7% decrease in latency, and an increase in network stability. A paired t-test yielded a p-value of 0.003 (<0.05), proving a significant difference before and after implementation. Interviews revealed increased cloud access speeds, shorter upload/download times, and reduced work distractions due to access restrictions. From a security perspective, before the proxy was implemented, data traffic was vulnerable to information leaks and malware attacks. After implementation, these risks were successfully mitigated through filtering, ACLs, and activity logging that supports digital forensic analysis. Thus, the proxy server implementation proved effective in optimizing bandwidth, improving network security, and supporting company productivity. Keywords: proxy server, network security, bandwidth optimization, squid, computer network]]>
