Transmit voice signals over a network using packet switching
VoIP technology (Voice over IP) is the result of the need to transmit voice signals from multiple users over a network using packet switching (packet switching).
Before you go through the channel audio signals are converted to digital (compressed state – up to 40% of data), and this makes it very much to save on long distance and international calls.
In addition, such a relationship is of high quality information that is transmitted. Thus, the communication can be via the Internet or via dedicated digital circuits. IP-telephony has become popular and in demand because of its exchange rate, which allows you to send phone messages over IP. In order to provide a link on the Internet with the PSTN PSTN (Public Switched Telephone Network), using special VoIP- analog gateways.
How does VoIP Gateway works
VoIP channel comes from the voice signal directly to the IP-phone that is connected to the IP-based network, or the signal is routed to the mobile phone operator, on landline phone, which is connected to a standard telephone network PSTN or to a digital telephone that is connected to the digital network with integration network ISDN.
Thus, the particular application considered technology – IP-telephony transmits voice signals:
- from computer to computer
- PC-to-phone (analog, digital, IP- telephone, mobile)
- from phone to phone
To call, you need a provider that will provide IP-telephony services. It depends on him, how good is the voice quality, as well as how good is an internet connection.
VoIP technology allows different companies to create system, include corporate office and IP-telephony. In addition, they often support multiple functions and require quite small financial resources for their implementation.
Systems of office IP-telephony – it’s IP, PBX / IP ATC, Soft PBX, PBX software, VoIP PBX, which are the telephone system for private use.
VoIP is designed for voice packets based on IP-based networks. Application-level protocols can be divided into these types:
- open (public) – they apply to any browser if it supports the protocol HTTP (for transferring web pages) and the protocol FTP (for file transfer, posted on the website), for example, SIP and H 323;
- closed (private) – they can not be used by any application. For example, protocols Skinny / SCCP and Unistim, for transmitting signalling traffic.
Advantages of VoIP technology compared to PSTN:
- by reducing the operating time of the channel (blocked all possible pause) much more efficient use of bandwidth;
- You can add additional phone lines at home or in the office, while ‘free redirect the call number of the person who is calling you, will be determined, as well as the function is available redial;
- by encrypting the signal, and the establishment of its conformity to the transmitted data volume, you can make secure calls;
- if you have an internet connection, it does not matter where you are. Communication will work;
- integration with colleagues via the Internet (exchange of information during the interview, accessibility for calls to other subscribers, etc.);
- routing the call can be connected direct numbers anywhere in the world.
Due to the fact that the switched signals have a low utilization ratio, which leads to increased cost of transmitting voice information in the network PSTN.
At the same time, we can be proud of VoIP technology that allows operators to significantly reduce the cost of international and long-distance calls. This trend leads to a significant reduction in the cost of the company, which is displayed in the future on the results of its activities.
According to research of the market situation VoIP-services users prefer it this voice, less and less appealing to traditional and mobile communications.