With its unique approach, LDSP optimizes the performance of optical communication systems by treating the entire process as a deep learning structure. This adaptation not only reuses existing DSP modules but also paves the way for better performance through comprehensive module-level. Digital signal processing is the technological driver for energy-efficient and high-performance optical transport networks. It increases the robustness against transmission interferences and enables software control of the physical layer. Electronic Digital Signal Processing (DSP) is a key. DSP (Digital Signal Processing) refers to the use of digital computation to manipulate signals such as audio, video, or sensor data. It involves transforming real-world analog signals into digital form, processing them using mathematical algorithms, and converting the processed signals back to. This article explains the modulation formats used in coherent optical systems (QPSK, 8/16/64-QAM), how DSP and OSNR tradeoffs determine reach vs. capacity, why probabilistic constellation shaping (PCS) matters, and how pluggable coherent modules (QSFP-DD / ZR / ZR+) change deployment economics. The Marvell® PAM4 optical DSP portfolio, including Spica™ and Nova™ DSPs, addresses the critical the need for high-bandwidth optical interconnects to power AI infrastructure. Several digital modulations available (M-PAM, square M-QAM, M-PSK, OOK) to simulate IM-DD and coherent optical systems., DP-16QAM, DP-64QAM) that pack more data bits onto each symbol, enabling higher data rates within the same bandwidth.