- Real time fax using the T.38 protocol and T.38 based fax gateway devices installed on the IP network.
- Internet fax using fax machines compatible with the T.37 protocol. In this system, faxes can also be received as email attachments.
- Voice over IP (VoIP) based fax using G.711 technology to pass through VoIP gateways and the Internet.
Internet fax over IP services can give businesses substantial cost savings compared to traditional fax using long distance telephone connections.