VoIP PSTN How They Differ and How VOiP Will Rule In Future
VOiP PSTN - No Question but VOiP Will WIN!

VoIP PSTN comparisons are difficult to make, because each belongs to a different era, although both in a way perform may of the same functions .

PSTN stands for public switched telephone network. It is the network of the public circuit-switched telephone networks around the world, just as the internet is the network of the various IP-based packet-switched networks known as VOiP or Voice over Internet Protocol to you and me. PSTN is now very slow when compared to VOiP running on any reasonably up to date system, as it generally delivers data at only about 52 Kbps (52,000 bits per second).

Voice over Internet Protocol (VoIP), is the technology that allows you to make voice calls using a broadband Internet connection instead of a regular (or analog) phone line. Some VoIP services may only allow you to call other people using the same service, but others may allow you to call anyone who has a telephone number - including local, long distance, mobile, and international numbers.

PSTN is a hard wired connection which pre-dates all modern radio based transmission and is still in many commercial and industrial premises the installed phone system and is routed through the phone switchboard.

Due to its age and worldwide adoption PSTN is the oldest, slowest, and most common phone connection based on twisted-pair copper wires carrying analog data. Computers require modems to convert digital signals from the computer to the analog waveforms that travel across PSTN lines.

The advent of public circuit-switched telephone networks began when phone calls were being made beyond the limits of a small geographical area where circuits were not connected directly. The development of PSTN was a quiet revolution requiring a high degree of commercial co-operation and co-ordination across nations and continents.

Remote call locations use high usage so called “trunks” to complete connection between toll centers. For many years this was achieved using the PSTN, but increasingly now the phone system is becoming web based. At the moment though the system is in transition, and the VOiP systems offered rely on the PSTN system to complete the final leg in order to make calls to a subscriber’s telephone. In this way calls can be forwarded from PSTN to Skype remote user and vice versa, in fix transfer mode or free dial mode.

VoIP is a developing technology and it employs encoding schemes and compression technology to reduce the load it puts on the internet system. The effect is to reduce the size of the voice packets so they can be transmitted more efficiently.

Many telephone service providers will sell you calling contracts where phone minutes are free whether you dial via Skype or the PSTN. However, you will incur any (long distance) phone charges required to call their non-toll free number.

Phones that can display caller ID information can display a Skype user name with the provision of a special adapter. Many like to use the advanced call waiting handling feature offered by some equipment suppliers which allows for notification of incoming calls (whether Skype or PSTN) while the phone is in use, and lets users switch between the calls, or even link a Skype call with a PSTN call in a three-way conference.

Voice mails, and call backs requests and emails can in some systems be sent automatically to PSTN call center agents depending of their availability and of the inbound queue state. VOiP is more advanced than PSTN systems, and with VOiP businesses that (for example) need to relocate offices can easily take the phone system along. So, Voice over IP (VoIP) technology provides many advantages to companies and individuals over both traditional telephone services and traditional IP communications. But, like other technologies, it also brings with it the potential for abuse.

by  - 10/10/2009

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