If this service is used on a PBX system, please call 30667676 as the access number for IDD calls.

若本服务使用于集团电话系统（PBX），拨打长途时请使用30667676作为接入号码，听到欢迎词再输入长途号码。

youdao

IP telephony system can not only provide voice application, but also provide many kinds of intelligent services, it can replace the traditional Private Branch eXchange (PBX) system completely.

IP电话系统不仅能传输话音，而且能提供多种智能服务，完全可以取代传统的个人分支交换(PBX)系统。

youdao

Using software you install on your PC, you can take complete control over all the phones in the house and turn your internal phone network into a system like a private branch exchange (PBX) not unlike what you might find at the office.

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