A seamless communication environment, where the limitations of time & distance would be eliminated is surely the ultimate objective behind newer inventions in the communication arena. VoIP technology holds great promise as it keeps evolving itself by providing newer applications.

But has VoIP truly arrived and is it completely ready to replace PSTN? Thats the big question. To know the answer we have to peep a little deeper into the technological aspects of them and try to know their real worth.

PSTN (Public Switched Telephone Network): Its the existing system based on circuit switching, the silent features

Advantages:
1) Well established technology
2) Easy maintenance
3) Hassle free set-up process
4) Simplicity in usage procedures

Disadvantages:
1) Dedicated line required to complete a call
2) Limited scalability
3) Optimum usage of bandwidth not possible
4) Monthly fees applicable for maintenance
5) Higher call charges

VoIP (Voice over Internet Protocol): The latest technology on the block, it employs the packet switching method of data transmission leading to an increase in the effective rate of transmission.

Advantages:
1) Concurrent transmission of data, voice & video possible
2) Scalability
3) As the data is sent over the network in compressed format, proper utilization of bandwidth is rendered possible
4) The World Wide Web, which is in the public domain, is used as the backbone of the network, thats why hardware requirements are a bare minimum.
5) The enhanced efficiency which becomes evident due to the proper utilization of bandwidth leads to massive reduction in the costs incurred per call. Thereby making VoIP a very cheap, yet effective communication tool.
6) Value added services are offered free of cost.
Disadvantages:
1) The quality of sound at times become unpredictable
2) Echo

VoIP is a near perfect technology as the disadvantages associated with it, are to a great extent in the domain of the VoIP service provider, so by choosing a reliable service provider you can hope to eliminate the disadvantages.

Coming back to the big question about choosing in between VoIP & PSTN, as of now it would be advisable to use a hybrid system with VoIP being in the core of the system & PSTN in the periphery. This arrangement would ensure that you get most of both the technologies and would not be dependent on one.

Although the near future would see VoIP completely overtaking the existing system, so by switching over to VoIP now on one hand you will witness massive savings and on the other hand get to have a feel of the technology of the future!!