As carrier network, optical transport network must be built prior to the 3g service network.

作为业务承载网络的3g光传送网，必须要先于业务网络的建设而建设。

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As carrier network, optical transport network must be built prior to the 3g service network.

作为业务承载网络的3g光传送网，必须要先于业务网络的建设而建设。

youdao