In 4G networks, the optical modules used to connect BBU and RRU are mainly gigabit to 10Gbit optical modules. The 10G SFP+ dual fiber optical module of ETU-LINK has a maximum speed of 10Gbps, complies with SFP + MSA, 10G Ethernet and 10g CPRI standards, and the transmission distance through OS2 single-mode optical fiber can be up to 80km. This module adopts 1310nm/1550nm conventional wavelength, DFB laser. BlazingFast Photonics delivers high-speed optical transceivers, silicon photonics, co-packaged optics, OSFP 1. Difference Between AAU, RRU, and BBU AAU, RRU, and BBU are key components in a telecom network. The base station can be divided into two modules: the RRU for transmitting signals and the BBU for processing signals.