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What are VoIP, PSTN, and POTS ?

  • Last Updated : 01 Apr, 2020

In earlier times, we all were aware of only two terms related to telecommunication. Those two terms were a telephone and a telephone number. Apart from these two, we weren’t knowledgeable about the ‘modern’ age terms (systems, to be precise) like VoIP, PSTN, SIP, POTS, and many more.

These terms play a significant role in the telephonic industry. Or, we can say that today, one can not imagine the world of communication without these terms.

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So, it is very important to have a basic understanding of these. Today, our main emphasis will be on VoIP, POTS, and PSTN. So, without further ado, let’s move forward with VoIP first.

  1. Voice over Internet Protocol (VoIP):
    VoIP is an acronym for ‘Voice over Internet Protocol’. As the name itself enunciates, it is a system in which the voice communications are sent over an ‘Internet’ i.e. on a wireless network rather than transmitting the same over wired networks for better security and end response. In this system, the audio signals are converted to digital signals which are disseminated through the internet.
  2. Public Switched Telephone Network (PSTN):
    PSTN is an acronym for ‘Public Switched Telephone Network’ and it is a sort of system in which the telephones pertain to the assigned networks.

    In moral terms, in PSTN, there are telephone numbers allotted to each telephone, one at the receiving end and one at the transmitting end (both numbers are unique!) and for any sort of communication between two individuals at either end, either of them should know the correct number of the other.

    In a PSTN system, signals aren’t converted to any other form like in the case of VoIP.

  3. Plain Old Telephone Service (POTS):
    To a newbie, POTS may appear a new technology in the field of telecommunication.
    But in reality, POTS merely stands for ‘Plain Old Telephone Service’. But initially, POTS was the acronym for ‘Post Office Telephone Service’. A simple reason was that, at that time, the post office was the sole source of communication of point A to point B.

    POTS is an old system of communication. In POTS, analog voice transmission takes place over a pair of twisted copper wire. This system has its roots from ancient times and thus, must be known to everyone.

    If even not, just get out of your home and look overhead. If a crammed combination of thick wires hangs between two poles, that’s POTS. Through those copper wires, the voice signals travel from point A to point B.

So, VoIP and PSTN can be regarded as the advancements over POTS in the field of telecommunication. This is because there were many problems related to this POTS system. A common problem associated with POTS includes distortion in voice while communicating over a telephone.

So, this was all about the three popular terminologies i.e. VoIP, POTS, and PSTN common in telecommunication.

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