VoIP

What is VoIP?

            
Voice over Internet Protocol (VoIP) is a method of making phone calls over the Internet. Unlike the old landline telephone system, the Internet was not designed to transmit audio signals in real time between connected people. Specialized technologies and protocols had to be built to make this possible, and these technologies and protocols make up VoIP, which today is an efficient method of real-time audio and video communication.

             

VoIP has been widely adopted. In many industries, it is the dominant form of telephone system, replacing landlines.

                   

VoIP has several advantages over landlines. It is more flexible, it is easier to add lines, it is often cheaper than traditional phone service, it supports video as well as audio, and it can be used from any location.

             

However, VoIP is susceptible to service disruptions and cyberattacks, which landlines are mostly immune to (e.g., DDoS attacks.) VoIP also relies on a stable Internet connection and power supply.

 

VoIP Applications

  

VoIP brings together various modes of communication into a single integrated platform. This integration means that VoIP not only facilitates audio communications, but also supports video conferencing, instant messaging and text-based interactions. Such an integrated system is particularly beneficial to businesses, as it simplifies team collaboration across a variety of communication channels without the need to use disparate applications.

 

In practice, VoIP provides the foundation for such cohesive communications environments by allowing individuals to make voice calls and participate in web conferencing from a range of devices, from desktop computers to smartphones and tablets.

 

How does VoIP work?

   

By the literal meaning of Voice over IP,  it can be directly translated as voice or video signals transmitted over IP networks, so VoIP is a technology that allows the transmission of analog audio or video over IP networks. Simply put, it is a series of transcoding, encoding, compression, packaging and other procedures so that the voice data can be transmitted to the destination over the IP network and then through the opposite process to restore the original voice signal for the receiver to receive.

   

Further, VoIP transmits voice signals to each other through a five-stage process. The first stage is to encode the analog voice signals of the sender, which is currently converted using the ITU-T G.711 voice coding standard. The second process is to compress the voice packets and add address and control information, so that in the third stage, that is, the transmission of IP packets stage, in the vast IP network to find the destination of the transmission. At the destination, the IP packets are decoded and converted into analog audio that can be played back by speakers, earpieces, or headphones.

      

In a basic VoIP architecture, there are four essential elements:

    

Media Gateway: It mainly converts voice signals into IP packets.

   

Media Gateway Controller: It is mainly responsible for managing signal transmission and conversion work.

  

Voice Intercom Server: Mainly provides voice response service when the telephone is not available, occupied or busy.

  

Signaling Gateway: The main work is to carry out relevant control in the exchange process to decide whether the call is established or not, as well as to provide value-added services for relevant applications.

   

What Causes VoIP Service Interruptions?

        

Poor Internet Connection: A low bandwidth Internet connection makes it difficult for packets to pass through, which can affect audio quality. No Internet connection means VoIP won't work at all.

   

Network congestion: If too much data is exchanged over the network at one time, VoIP phones may not be able to transmit packets efficiently - just as too many cars on a highway slows down travel speeds.

   

UDP Timeout: As mentioned above, VoIP typically runs on the UDP transport protocol. Firewalls may terminate UDP connections that exceed a certain time for security reasons.

     

Network Attacks: Like any Internet-based service, VoIP is vulnerable to attacks. In particular, VoIP services are often the target of Distributed Denial of Service (DDoS) attacks. These attacks can take VoIP services offline for minutes, hours or days at a time.