PSTN vs VoIP: What's the Difference?

PSTN (public switched telephone network) is the traditional phone network of carrier lines and exchanges. VoIP (voice over internet protocol) carries calls as data over the internet. Most cloud calling systems use VoIP for agents and connect to the PSTN through carriers, so customers can be reached on any ordinary phone number.

How it works in Salesforce

For a Salesforce calling team, the difference shows up in setup and flexibility:

• PSTN: calls run over carrier lines, often through a desk phone or an office phone system. Reliable, but tied to physical lines and locations.
• VoIP: agents call from a browser or app over the internet, so they can work from anywhere with a good connection. New numbers and agents can be added in minutes.

A typical cloud setup combines both. The agent's softphone in Salesforce uses VoIP, and the provider hands the call to the PSTN to reach the customer's mobile or landline. Call quality depends on the agent's internet connection, so a stable network and a good headset matter.

Some countries regulate how VoIP and PSTN can connect for business calling, so setups can differ by country.

Example

A remote sales team calls customers from the Salesforce softphone over VoIP. Each call reaches the customer's mobile number through the carrier's PSTN connection, and the customer sees a normal business number.

How 360 CTI handles it

360 CTI connects cloud calling to Salesforce for in-office and remote teams. For setups in India, see the Call Flow PSTN and VoIP guide, and see the Cloud Contact Center solution.

Related questions

Follow-up questions