For acceptable voice calls, the packet error rate should be less than（）%
第1题：
A global manufacturer of automobile parts wants to implement specialized voice applications to increase productivity and reduce the cost of overseas toll calls. Which Cisco solution best matches this business need?（）
A.Digital subscriber line (DSL)
B.Optical network
C.Wireless local-area network (WLAN)
D.Internet Protocol (IP) telephony
第2题：
【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 that opreate over a LAN, thus converging two systems into one. A second common solution is the one often encountered at home. Using existing telephones, a special converter is added between the telephone and a high speed internet（DSL or cable modem）connection. The converter digitizes the voice signal and creates a stream of packets that are then sent over an ip connection.The third technique involves smart cell phones. Never cell technologies are all packet-based, thus requiring a telephone call to be converted to digital packets and sending those packets over IP networks.】
From the paragraph above，a popular service that has attracetd the interest of companies and home users,is termed as （） . The data transfer over the Internet is controlled by the （） . At corporate level, many companies have replaced their older internal telephone systerms with （） that oprerate over a local area network.
A、voice over the internet B、voice over packet C、Voice over IP D、internet telephony A、packet B、internet protocol C、industry D、VoIp servers A、VoIP systems B、IP-enablde telephones C、VoIP servers D、routers
第3题：
Today the energy problem becomes critical. It ____ an immediate solution.
A calls on B calls for C calls up D calls at
第4题：
Voice activity detection （VAD） suppresses the transmission of silence patterns. On average， and assuming that a link carries at least 24 calls， what percentage of total bandwidth could VAD save？（）
第5题：
What can be used to maintain the voice quality on a link by limiting the number of calls that can be active at any given time？（）
第6题：
A.0.01
B.0.1
C.1
D.2.5
第7题：
For acceptable voice calls， the packet error rate should be no higher than what value？（）
第8题：
A good writing _____ clear organization and choice of words.
A calls on
B calls for
C calls up
D calls off
第9题：
Which two statements are true about voice ports on a router？ （）
第10题：
A global manufacturer of automobile parts wants to implement specialized voice applications to increase productivity and reduce the cost of overseas toll calls. Which Cisco solution best matches this business need?（）