Voice Over Internet ProtocolVoip Essay Research Paper

  • Просмотров 178
  • Скачиваний 5
  • Размер файла 18
    Кб

Voice Over Internet Protocol(Voip) Essay, Research Paper VOICE OVER INTERNET PROOL (VoIP) INTRODUCTION: In the eyes of most, all packets are created equal. One of the most active areas of telecommunications today is in the area of Voice over Internet Protocol (VoIP). The logic behind this trend makes perfect sense. If we have invested heavily in an Internet Protocol (IP) network, why can’t we make full use of it? This is a question posed by many managers and Information Technology (IT) professionals in a wide range of businesses. Many businesses would prefer to have one network in and out of their business for reasons ranging from cost effectiveness to manageability. IP telephony offers a promise of consolidation. This will allow an enterprise to converge its traditional

phone system and newer data network for greater efficiency. Arieh Dranger, president of neXTel Systems LLC says, “I don’t think it’s a question of whether we need VoIP, but when it will come together, because it represents a natural progress of integrating data—period. The IP protocol is probably the most efficient at combining a universal communications network.” Basically, IP telephony is taking the telecom world by storm. It has evolved from a little known and used application in 1995 to an application that is poised for global adoption. But as with all technology, there is a price to be paid, and several entities vying for a piece of the pie. WHAT IS VoIP and HOW DOES IT WORK? To put it simply, VoIP means Voice over Internet Protocol. It’s a technology that allows

network managers to route phone call over the network they use for data transmission. A voice travels over a corporate Intranet or the Internet instead of the public telephone system. Special gateways installed at both the sending and receiving end of a communications channel converts voice to IP packets and back again to voice. This process must take place in a time frame of less than 100 milliseconds to sustain the Quality of Service (QoS) that users are accustomed to from the Public Switched Telephone Network (PSTN). Now let’s take a walk on the more detailed side of what VoIP is and how it works. First and foremost, VoIP is an emerging technology still in the early stages. A personal computer (PC) must capture an analog voice and convert it to a digital signal, compress the

audio with a compression-decompression (codec) device and then move it into the IP protocol stack. The codecs are at the heart of any IP telephony software. It is an algorithm that transforms analogue signals into digital ones and vice versa. The next step is to access the network, which is the premise modem connected to the PSTN and channeled to the Internet Service Provider (ISP) modem. The next link in the chain of events is the IP network itself or the Internet. The current structure of the Internet can make it an unstable and unpredictable carrier. Finally, the voice packet must transition back from the IP network to the PSTN, to the receivers’ modem for conversion back into analog. Each of these steps adds more delay to the voice packets. A delay approximately of over 550

milliseconds, which is 400 msecs over the QoS acceptable limit, is found to occur. These delays and other issues are just some of the challenges facing the future of VoIP. WHY IS VoIP AN ISSUE? Between 1994 and 1997 ISP revenue grew from about $189 million to over $4.75 billion dollars, making it the telecommunications success story of the nineties. This extraordinary growth, coupled with relatively inexpensive connectivity for the typical user has helped drive the emergence of VoIP. To the typical personal user, this technology will mean nothing more than the ability to make “free” long distance phone calls. However, to the business world, this technology holds some very profound promises. It’s the ability to avoid long distance phone charges that has many scrambling to