Зачётная работа по английскому
контрольные работы, английский язык
Год сдачи: 2012
Стоимость: 200 руб.
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WHAT IS VOIP?
1. Voice Over Inte
et Protocol (VoIP) is a new technology that uses broadband Inte
et and network lines to transmit real-time voice information. This technology has the potential for completely changing the way phone calls are made and making phone companies a thing of the past.
2. To make a phone call on the Inte
et, several things must happen. On the sending side, analog voice signals are digitized, compressed, divided into packets and transmitted over network lines. On the receiving end, the signals are recombined, uncompressed and converted back into audio. Because the voice signals are digital, they can be transmitted just like any other data packets on a network. VoIP can be relatively inexpensive to implement, although costs rise as the complexity of the system increases.
3. There are currently several problems with this technology. If the computer or network lines fail, then telephone service is interrupted. Though the stability of computer hardware, operating systems and network infrastructure has improved significantly in the last decade, crashes still occur. The "up" time of these systems is still significantly less than with traditional phone systems - which often continue to function even during power outages. Another issue is that tracking the origin of a call is difficult because the signals are transmitted over the Inte
et. This is especially important to emergency responders to 911 calls. Caller ID service may not function either.
4. Additionally, devices that make calls using phone lines, such as fax machines, cable TV boxes, etc. may not function properly. Law enforcement officials may have difficulty wiretapping phone lines that use VoIP technology. Finally, the quality of VoIP service is lower than that of a traditional phone system. Since the information is transmitted over network lines, VoIP phone calls may break up, hesitate, or cause...
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