We propose a multi-user low-upstream-loss PON utilizing graded-index multi-mode fiber (GI-MMF) and a compact ODN constructed by a multi-mode transformer (MMT) for the first time. An Optical Distribution Network (ODN) is the passive fiber infrastructure that connects the Optical Line Terminal (OLT) in the central office to the Optical Network Unit (ONU/ONT) at the subscriber side. Unlike active equipment, the ODN does not require electrical power. 9807 (XGS-PON), and IEC 60794 cable standards, the ODN forms the physical optical path responsible. The ODN network devices provide the optical fiber interconnection or cross-connection, optical fiber splicing, optical power distribution/wavelength distribution, and optical path protection functions.