The emergence of the 800G QSFP-DD 2FR4 optical module provides a more efficient data transmission solution for networks. The 800G QSFP-DD 2FR4 module employs 8x 100Gbps PAM4 modulation technology, and supports a maximum data rate of 850Gbps. Ethernet signals are transmitted through four wavelengths: 1271nm, 1291nm, 1311nm, and 1331nm. It enables the fiber link of 2km over single-mode fiber with dual duplex CS connectors. Let's explore two practical application scenarios next.