VoIP (Voice-over-IP) - the communication system, providing the transmission of voice signals over the Internet or through any other IP-networks. The signal on the communication channel is transmitted in digital form and before sending the converted and compressed. Typically, telephone service via VoIP, especially long-distance and international, are considerably cheaper than conventional or cellular. This is conditioned by the fact that the transmission of voice traffic over the Internet much cheaper than through a network of mobile operators, Internet access is much cheaper than laying and connection of telephone line. In addition, VoIP would be considered as an information service and therefore exempt from taxation, which allows providers to establish communications VoIP-low rates are not at a loss. Shikorokopolosny Internet access to use the VoIP-telephony is not necessary, it is enough speed to 64 kb / c. There are many voip providers.
Currently, there are some basic standards for working with VoIP and a huge number of codecs used for voice transmission. The most common is the open standard SIP (Session Initiation Protocol). It uses most of the operators of Internet telephony throughout the world, and under it says a lot of so-called softofonov - programs used to communicate via VoIP. We offer voip review in many countries.
Roughly equal to spread it is safe to assume a closed standard Skype, Skype was created by developers on the basis of network P2P. There are several private, or proprietary protocols, but they are less common. Typically, each provider using a closed communications protocol has its own client software that is incompatible with the others.
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