(FTTH (FiberToTheHome), as the name suggests, is an optical fiber directly to the home. Specifically, FTTH refers to the installation of optical network units (ONUs) at home users or enterprise users. It is the type of optical access network that is closest to users in the optical access series except FTTD (fiber to the desktop). The significant technical attribute of FTTH is that it not only provides greater bandwidth, but also enhances the transparency of the network to data formats, rates, wavelengths and protocols, relaxes the requirements for environmental conditions and power supply, and simplifies maintenance and installation.)