Technically speaking, VoIP is method for taking analog audio signals and turning them in to digital data to be transmitted over the internet. Economically speaking, it’s a way of reducing the cost of a long-distance call to 1/10th its current cost. How is this possible? Most phone lines use what is called circuit-switched network. Once communication is established, the line is kept open for the two communicating people until the phone is hung up. You pay for the whole duration although you actually use the line for sending audio signals only half the time(the other half you’re listening to the other person speaking). In addition, when speaking, there are intervals where you don’t say anything at all, for example when you are taking a breath. With VoIP, the audio signals are rid of these silent intervals, then changed into one digital file. The file is chopped into small packets and sent over the internet. While circuit switching keeps the line continuouslyopen, packet switching opens connection for a brief moment only when there is a packets to be sent or retrieved. Furtermore, instead of sending the packets over one dedicated line, packet switching sends them through different network, each time letting the network find the least congested and cheapest line.
VoIP calls can be made from PC to Pc using softweres (Yahoo!Messenger, Google Talk, Skype, etc), a sound card, a headset, and fast internet connection (not a dial-up); there’s no charge except for the normal ISP bill. You can also call frome a home phone using an analog telephone adaptor, or from a a special IP phone, with VoIP services from a VoIP provide; thus song distance rates are much reduced, and browsing and downloading services are included.
With lower prices and flexibility as the upshot, the VoIP services can easily win over conventional phone customers. In fact. more and more phone companies offer VoIP services to their customers, especially for bussines, for example XL, Telkomsel or into Asia Telcom.
On the other hand, VoIP has a major flaw; reliability. VoIP phones depend on electricity, no communication. VoIP is also susceptible to internet problems like packets loss (resulting in garbled voice), delay, viruses, and hackings. In addition, infrastructure and regulationin Indonesia Still hamper the developmentof VoIP and its providers. Internet access in Indonesia is still too expensive, not to mention slow. Besides, government regulation restrict the linking of VoIP network to telkom’s.
Hopefully, in the future, all of these problems can be solved so that customers can get the most out of this technology.
Tri Indaryati; 2011; English Alive (Senior High School).