计算机唯一可以识别并执行的语音是（）。

在通信专业中，MAC 的英文全称是（），调制的英文通常翻译为（）。

In the twenty-first century, broadband networks need to be considered as basic critical（）like roads, railways, water, and power networks.

In addition mobile users also expect to connect to the （） for communications and access to services （） the best suitable connection,any where and at anytime.

The exponential growth of mobile broadband traffic is certainly （） by both, the increasing demand for known and new data services,such as mobile internet access, social networking,location-based services/personal navigation and so on, and the data （） and storage capabilities of state-of-the-art terminals, such as smartphones and the most recent tablets.

【A popular service that has attercted the interest of companies and has home users alike is the sending of voice signals over an IP-based network, such as the Internet. The practice of making telephone calls over the internet has had a number of different names, including packet voice, voice over packet, voice over the internet, internet telephone, and Voice over Ip（Voip）. But it appears the industry has settled on the term”Voice ove IP” in reference to the internet protocol, which controls the transfer of data over the internet. There are currently three ways to deliver VoIp to users, the first technique is found at the corporate level. Many companies are offering VoIP systerms that operate over a local area network. These systems involve a fair amount of equipment, such as VoIP servers, special IP-enabled telephones, and routers that can direct telephone calls. Today a large portion of corporate sites have converted their older internal telephone systems to VoIP systems t