This paper presents a 32 × 4 optical switch designed for ROADM (Reconfigurable Optical Add-Drop Multiplexer) applications, using high-index doped silica glass (HDSG) to achieve low insertion loss (IL) and polarization-dependent loss (PDL). The switch is composed of 188 Mach-Zehnder Interferometer (MZI) elements, 88 optical vias, and 618 waveguide-waveguide crossings with a 3D integration process. Key performance metrics include fiber-to-fiber losses of below 2 dB for express channels and below 3 dB across the C and L bands. The PDL for all channels is below 0.3 dB in the C band, and crosstalk is under −50 dB for both C and L bands. The switch's architecture and design details are discussed, along with its performance in transmission experiments, demonstrating low BER and high efficiency. The HDSG platform's moderate index contrast (10% to 20%) balances fiber coupling loss, propagation loss, and PDL, making it suitable for compact and robust ROADM solutions.This paper presents a 32 × 4 optical switch designed for ROADM (Reconfigurable Optical Add-Drop Multiplexer) applications, using high-index doped silica glass (HDSG) to achieve low insertion loss (IL) and polarization-dependent loss (PDL). The switch is composed of 188 Mach-Zehnder Interferometer (MZI) elements, 88 optical vias, and 618 waveguide-waveguide crossings with a 3D integration process. Key performance metrics include fiber-to-fiber losses of below 2 dB for express channels and below 3 dB across the C and L bands. The PDL for all channels is below 0.3 dB in the C band, and crosstalk is under −50 dB for both C and L bands. The switch's architecture and design details are discussed, along with its performance in transmission experiments, demonstrating low BER and high efficiency. The HDSG platform's moderate index contrast (10% to 20%) balances fiber coupling loss, propagation loss, and PDL, making it suitable for compact and robust ROADM solutions.