Definition of: ISDN (Integrated Services digital Network) an international standard for switched, digital dial-up telephone service for voice and data.

定义：ISDN(综合服务数字网络)，是一个国际转换标准，是为了语音和数据的数码拨号上网电话服务。

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Right now the company relies on dial-up ISDN and 56K bps modems for most of its Internet access.

CNN: Europe's first ADSL service launches

Not only were computer dial-up offerings delayed, but higher speed ISDN and DSL services went almost entirely to competitors.

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