VoIP (Voice over Internet Protocol) technology has become increasingly popular in recent years as a way to conduct voice communication over the internet. A VoIP number is any number that doesn’t terminate on a physical handset.
In contrast with comparable technology on the public switched telephone network (PSTN), messaging on VoIP lines is not commonly supported. Unlike phone calls, which use standard protocols such as SIP (Session Initiation Protocol), VoIP messaging has no agreed-upon protocol that allows different VoIP systems to communicate with each other via text.