ISPs are all connected to each other through network access points, public network facilities on the Internet backbone.

所有的网际网络服务提供者透过网络存取点，网际网络骨干的公用网络设施彼此连接。

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These tier-one ISPs then sell backbone access to smaller ISPs, which then sell it to yet smaller ISPs, and so on down the Internet food chain.

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The IAPs connect internally to three Internet exchange points run by the state, and the IAPs also grant the regional Internet service providers (ISPs) access to backbone connections.

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