中国钟学我术大草 信息网给与协议 VERIITY OF SCIENCE AND TECHNOLOOY O年C框NA 固网接入：光进铜退 Optical fiber Copper cable Service provider Node/Cabinet Building Home Modem CO DSLAM FTTN (ADSL2+) End- Modem nser Modem CO CATV Cabinet FTTCab (HFC) End- Modem user Passive splitter/ ONU combiner CO FTTH (PON) ONU End- user信息网络与协议 5 固网接入：光进铜退