This document presents a performance analysis of an IP over optical CDMA network system based on a random diagonal (RD) code. It proposes using spectral amplitude coding OCDMA to directly connect the IP layer to the optical layer, eliminating intermediate layers and reducing overhead. The system architecture, design steps, and simulation setup are described. Simulation results using OptiSystem show that bit error rate increases with the number of simultaneous users and data transmission capacity decreases with transmission distance as expected. The RD code OCDMA system provides a potential solution for next-generation networks by enabling intelligent functions and advanced services at the optical layer.