VoIP Fundamentals
Recent happenings like Internet diffusion at low cost, coupled with great computer availability, new integration of dedicated voice compression processors and an evergrowing need for instant, around-the-world communication have changed common user requirements allowing VoIP standards to diffuse.
VoIP stands for Voice over Internet Protocol. Thus, VoIP attempts to transfer voice through IP packets and use the already established Internet infrastructure. VoIP is about digitizing voice signals, sending them over the Internet and transforming the digital packets into analog signals at the destination. The advantages of this protocol, as opposed to regular, PSTN phone lines, would be the possibility to talk to more than one person at one time, the costs would reflect the amount of data sent and received and not the length of time spent on the VoIP phone and, last but not least important, all the advantages of using a PC (exchanging data with the participants to a discussion, video feed that could enhance the conversation, etcaetera).
The disadvantages, so far, are generated by the same elements that make VoIP available: the heterogeneous structure of the Internet. The lack of a largely accepted standard, the “best effort†approach to the way packets of data move between source and destination, high round trip time make VoIP a difficult protocol to implement, especially since voice communication must be a real time process. Efforts are underway to make this protocol available to the masses, and large companies have already started implementing it, though the time high speed internet and computer assisted voice communication over IP replace regular phone lines is not too close at hand. Voice over IP Fundamentals is a good reference for what VoIP stands, and even though the writing style is conversational, there is much information that needs to be gone over with patience. The 300+ tome is structured into 15 chapters that deal with the basics of the regular phone system (PSTN) and the Internet Protocol, voice modulation, signaling protocols like Signaling System 7, Quality of Service issues and the Session Initiation Protocol (SIP).
Voice over IP Fundamentals sheds some light on topics including network losses due to jitter, latency and packet loss, and addresses Quality of Service issues that need to be considered when deploying a VoIP solution. It also makes some considerations on the possibilities of the VoIP from an economical standpoint, illuminating the advantages voice over IP can bring.
The book offers many examples and helps the understanding of the described technologies by using diagrams and case studies, frequently comparing with Cisco products that achieve the illustrated goals, but as part of the Networking Technology Series from Cisco Press, it is understandable.
The authors´ knowledge of the facts they are presenting can aid the data network professional in understanding voice telecommunications and applying the knowledge to creating a Voice over IP system that doesn’t sacrifice quality to cost.
VoIP stands for Voice over Internet Protocol. Thus, VoIP attempts to transfer voice through IP packets and use the already established Internet infrastructure. VoIP is about digitizing voice signals, sending them over the Internet and transforming the digital packets into analog signals at the destination. The advantages of this protocol, as opposed to regular, PSTN phone lines, would be the possibility to talk to more than one person at one time, the costs would reflect the amount of data sent and received and not the length of time spent on the VoIP phone and, last but not least important, all the advantages of using a PC (exchanging data with the participants to a discussion, video feed that could enhance the conversation, etcaetera).
The disadvantages, so far, are generated by the same elements that make VoIP available: the heterogeneous structure of the Internet. The lack of a largely accepted standard, the “best effort†approach to the way packets of data move between source and destination, high round trip time make VoIP a difficult protocol to implement, especially since voice communication must be a real time process. Efforts are underway to make this protocol available to the masses, and large companies have already started implementing it, though the time high speed internet and computer assisted voice communication over IP replace regular phone lines is not too close at hand. Voice over IP Fundamentals is a good reference for what VoIP stands, and even though the writing style is conversational, there is much information that needs to be gone over with patience. The 300+ tome is structured into 15 chapters that deal with the basics of the regular phone system (PSTN) and the Internet Protocol, voice modulation, signaling protocols like Signaling System 7, Quality of Service issues and the Session Initiation Protocol (SIP).
Voice over IP Fundamentals sheds some light on topics including network losses due to jitter, latency and packet loss, and addresses Quality of Service issues that need to be considered when deploying a VoIP solution. It also makes some considerations on the possibilities of the VoIP from an economical standpoint, illuminating the advantages voice over IP can bring.
The book offers many examples and helps the understanding of the described technologies by using diagrams and case studies, frequently comparing with Cisco products that achieve the illustrated goals, but as part of the Networking Technology Series from Cisco Press, it is understandable.
The authors´ knowledge of the facts they are presenting can aid the data network professional in understanding voice telecommunications and applying the knowledge to creating a Voice over IP system that doesn’t sacrifice quality to cost.
