Drew Bixby
Read Time: 2 minutes

What is PSTN? What does it mean to you and your company? Has your company made the change to Voice over Internet Protocol (VoIP) or any new voice services? If not, you are falling behind the pack. PSTN or Public Switch Telephone Network is referred to as the Plain Old Telephone Service or POTS. The demand from business is dramatically declining for PSTN. Service providers are transitioning away from their “plain old telephone system” (POTS) infrastructure towards VoIP alternatives. Enterprises have to prepare for a change sooner rather than later.

This is with respect to newer IP telephony networks based on newer communication technologies. VoIP, in contrast to PSTN, uses what is called packet-switched telephony. Using this system, the voice information travels to its destination in countless individual network packets across the Internet. This type of communication presents special TCP/IP challenges because the Internet wasn’t really designed for the kind of real-time communication a phone call represents.

Individual packets may — and almost always do — take different paths to the same place. It’s not enough to simply get VoIP packets to their destination. They must arrive through an extremely narrow time window and also be assembled in the correct order to be intelligible to the recipient. If not the call will be choppy and broken. VoIP employs encoding schemes and compression technology to reduce the size of the voice packets so they can be transmitted more efficiently and timely. This, in turn, makes for a very clear call experience. VoIP technology has come a very long way and is becoming the preferred communication technology of today.


PSTN is widely used in home phone service. Today companies of all sizes are moving to VoIP phone service. The benefits of VoIP far exceed that of its former PSTN. Not only will companies save 50% or more, but VoIP is also much more scalable. Unlike PSTN, VoIP offers free VoIP to VoIP calling anywhere in the world. VoIP utilizes the internet, while PSTN uses dedicated lines.

If you are still on the fence about whether or not to make the switch, below you will find a quick comparison of the two.


All channels carried over your current Internet connection

Compression can result in 10kbps (in each direction) which is much less than PSTN

Features such as call waiting, Caller ID, and call forwarding normally included free with service

Upgrades required are only bandwidth and software upgrades (may not need bandwidth depending on your current)  which is a much cheaper investment than PSTN

Long distance is usually included in your regular monthly price. Again, much cheaper than PSTN

911 emergency calls cannot always be traced to a specific geographic location

50% or cheaper than PSTN


Dedicated Lines

Each line is 64kbps in each direction, which is much more than VoIP

Features such as call waiting, Caller ID, and call forwarding are usually available at an extra cost

Can be upgraded or expanded with new equipment and line provisioning which can get very complex and expensive hardware

Long distance is usually per minute or bundled minute subscription which can be very costly for companies. VoIP is much cheaper

Hardwired landlines (those without an adapter) usually remain active during the power outage

Calls to 911 can be traced to your specific location

PSTN is exceedingly becoming ancient technology and VoIP is the wave of the future. If companies want to achieve certain business goals, they have to move to VoIP because their traditional phone service is not going to be able to provide the new functionality required by agile businesses with multiple sites and mobile and remote workers.