Tsinghua University Tsinghua University Tsinghua University Tsinghua University Tsinghua University This document presents a detailed analysis of the problems and requirements of network addressing in "Internet in space" for terrestrial users. It introduces the basics of satellite mega- constellations, terrestrial terminals/ground stations, and their inter-networking. Then it explicitly analyzes how space-terrestrial mobility yeilds challenges for the logical topology, addressing, and their impact on routing. The requirements of addressing in the space-terrestrial network are discussed in detail, including uniqueness, stability, locality, scalability, efficiency and backward compatibility with terrestrial Internet. The problems and requirements of network addressing in space-terrestrial networks are finally outlined.