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3.1 Telecommunication Cable Line Network Architecture
3.1.1 Telecommunication cable line network（Figure 3.1.1）shall include long-distance lines，local lines and access lines，using transmission media such as optical cables and copper cables.
Figure 3.1.1 Reference model for communications networks
3.1.2 The access network part（Figure 3.1.2）shall include primary cables，secondary cables and user drop wires，using transmission media such as optical cables and copper cables.
Figure 3.1.2 Structure of access network lines