The concept VoIP refers basically to voice over Internet Protocol. What does it mean? It means that voice can go through the internet. It is also known as Internet telephony. The difference between VoIP and traditional telephony is that VoIP sends all its data (voice signals and its encoding) over the internet, and traditional telephony does it over public switched telephone network (PSTN), which is the network that operates in a city or specific region through its telecommunication infrastructure, like optic fiber cables, telephone line cables or microwave transmissions, among other elements. In other words, VoIP or Internet telephony is the communication over internet protocol (IP), while traditional telephony is the communication through telephony infrastructure.
It is the system of communicating rules that internet uses. In other words, it is the structure for instructions and policies where the internet runs, connects, sends and receives all its data.
The Internet Protocol defines IP addresses, which serve as the identification for data packets traveling through internet (from a host source to a host destination). An IP address is defined as an alpha numeric label that is part of a computer network connected to the internet system of rules (Internet Protocol). Essentially this addresses help to indicate where is located something on the internet.
In summary, the Internet Protocol is the system of rules where the internet works to send and receive data packs that are located somewhere having an IP address needed to locate them.
Understanding the concept of IP, the VoIP term can be understood as the pack of voice data that uses the internet to go from one side to another side. In other words, a phone call made through the Internet.
Gateways: It is a network dispositive that converts traditional phone calls into VoIP calls and vice versa, letting traditional telephony connects with IP telephony. Put differently, it is the bridge between traditional telephony and VoIP.
Servers: It is where all the data is managed and stored. It routes, collect, control and manage all the data registers of a phone call.
Client: It is where the data is decoded and sent to the telephone user, in other words, it is the link between the data that travels through the internet and the user who receive or send the voice data. This element could be a Softphone which is a software or App configured under the Internet Protocol the make and accept calls or IP phones, which are devices configured under the Internet Protocol.
In the develop of VoIP technology, there have been three generations offering different communication models under diverse technologies. At the beginning, voice IP technology was offered as a service model and was similar to the traditional telephony scheme. Currently, it is still used for some companies. This is known as the first generation of VoIP.
The second generation refers to those technologies like Skype, which offer a free service for private users and they need to have hardware and software to use it.
The third generation is the model which uses federated voice IP term. Under this scheme works WhatsApp calls or Gtalk calls. Basically, this generation refers to the possibility that users have to connect to different domains on the Internet without the need of a central point to route calls.
Federated VoIP concept
Under this VoIP model, users have the option to communicate through different domains without requiring a calls router, like other systems mentioned above. This means that with people can make calls over the internet without a virtual exchange central.
As mentioned before, VoIP works under Internet protocols. The currently VoIP protocols incorporate:
- Session Initiation Protocol (SIP)
- Media Gateway Control Protocol (MGCP)
- Gateway Control Protocol (H.248)
- Real-time Transport Protocol (RTP)
- Real-time Transport Control Protocol (RTCP)
- Secure Real-time Transport Protocol (SRTP)
- Session Description Protocol (SDP)
- Inter-Asterisk eXchange (IAX)
- Jingle XMPP VoIP extensions
- Skype protocol
These mentioned concepts are used presently for different VoIP systems, but there are some of them that are being more used than others due to the efficiency they give, like MGCP or SIP protocols.
Currently, companies and persons are using increasingly VoIP technology, due to its lower prices compared to traditional telephony. Besides, any person with an internet connection can use this technology through its laptop, tablet or cell phone, while traditional telephony can not. On the other hand, companies that use this technology, can reduce their communication costs and use multiple tools, like Gtalk, WhatsApp or Skype, to connect its employees, which traditional telephony can not do.
This technology is a great opportunity for people and companies, not only for reducing costs but for the penetration and ease it provides. Any person from anywhere at any time can communicate with other people if it has a tablet, laptop, cell phone or any other device that allows internet connection.