STA5 subscriber line is applied to subscriber line interface of programmed control digital switches, and two wire analogy remote interface of access network.

STA5型用户板用于数字程控交换机的用户接口，也可做为各类接入网系统的远端二线模拟接口。

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In the 1990s Covad built the nation's largest digital subscriber line (DSL) network, offering rapid net access, but fell into Chapter 11 and got delisted from Nasdaq.

FORBES: Trial by Fire

Defending BT's position as the dominant player in the ADSL (Asymmetric Digital Subscriber Line) market, chief executive Ben Verwaayen said looser regulation would encourage BT investors to create a 21st Century network.

BBC: NEWS | Technology | MPs hear evidence on UK broadband