1 发展接入网的几个关键因素1.1 宽带业务价值链的构建运营商建设宽带接入网络日趋理性。但从赢利模式上看,经营宽带网络主要的收入来源于用户网接入费,业务层次低,没有形成有效的宽带价值链。由于发展,宽带用户网及附属支出逐渐增加。但交给ISP的网络费用是固定的,增加 A few key factors in the development of access network 1.1 The construction of broadband service value chain Operators to build broadband access network has become increasingly rational. However, from the profit model point of view, the main revenue from the operation of broadband network comes from the user network access fee, business level is low, did not form an effective broadband value chain. As a result of the development, broadband user networks and affiliated expenditures gradually increase. However, the cost to the ISP network is fixed, increased