Implementasi sistem komunikasi data sangat penting dalam mendukung keandalan peralatan Operational Technology (OT) di lingkungan UP2B Jawa Tengah dan D.I. Yogyakarta. Penelitian ini membahas penggunaan perangkat multiplexer DFS14 (SDH) dan DB4X (PDH) sebagai backbone komunikasi data menggantikan sistem lama berbasis Cisco CGS 2520. Tujuannya adalah meningkatkan efisiensi, kecepatan, dan keandalan komunikasi antarperalatan OT. Metode yang digunakan meliputi observasi lapangan, wawancara teknis, dan analisis data availability komunikasi RTU tahun 2018 dan 2024. Hasil menunjukkan bahwa multiplexer membentuk topologi loop dengan jalur utama dan cadangan, memungkinkan redundansi saat gangguan terjadi. Availability komunikasi RTU meningkat signifikan, mencapai lebih dari 99% setelah implementasi. Kesimpulannya, penggunaan multiplexer berbasis SDH dan PDH terbukti meningkatkan performa komunikasi data OT, memperkuat keandalan sistem, dan layak dijadikan model untuk wilayah lain. Beberapa tantangan teknis dapat diatasi melalui pelatihan dan penyesuaian konfigurasi.

The implementation of data communication systems is crucial in supporting the reliability of Operational Technology (OT) equipment in the UP2B Central Java and Yogyakarta regions. This study discusses the use of multiplexer devices DFS14 (SDH) and DB4X (PDH) as the backbone of the data communication network,replacing the previous Cisco CGS 2520-based system. The objective is to enhance the efficiency, speed, and reliability of communication between OT equipment. The methodology includes field observations, technical interviews, and analysis of RTU communication availability data from 2018 and 2024. The results show that the multiplexer establishes a loop topology with primary and backup paths, enabling redundancy during transmission disruptions. RTU communication availability significantly increased, reaching over 99% after the implementation. In conclusion, the SDH and PDHbased multiplexer system has proven effective in improving OT data communication performance, strengthening network reliability, and is considered a viable model for other PLN regions. Several technical challenges were successfully addressed through structured training and configuration adjustments.