The white paper makes an in-depth analysis on current and future challenges that telecommunication network optimization & maintenance faces. It indicates that the next-generation SON (NG SON) based on Massive Data and Cloud Computing will realize automation and intellectualization of all work with known input and output in current network, and become the enabler of Cloud-RAN. It points out that the most important driver of NG SON is to improve operation efficiency with evolving MBB network. In addition, NG SON will be a built-in module in RAN, designed and developed with RAN together. New technologies and services such as scenario oriented SON, experience oriented SON and gird level SON are the vital capabilities of NG SON. This white paper has important reference value to the automotive O&M for 4.5G and 5G network.