Written by Topher Kessler
Faxing documents seems to be one of those antiquated technologies that is here to stay. Even with many digital alternatives available for sending and receiving documents, faxing refuses to be replaced and instead has kept up with current forms of communication, integrating into email and IP networking. Perhaps the idea of having an original copy is what makes faxing more appealing than emailing a Word or even a PDF document, but regardless of the reason, faxing is still around and quite commonly used.
Sending a standard fax
To send a standard fax from your computer, you will need a fax modem such as Apple's USB modem (though most USB fax modems will work just fine). After connecting the device it should be recognized in the "Print & Fax" system preferences (you may need to manually add it), and while you can set it up for use with an ISP, you do not need to do this for sending faxes. With the modem now attached to your home phone line, you should be able to print from any document and select the fax as your printer device, then enter a proper fax phone number and send the fax away.
Faxing over VoIP connections
Unlike standard phone lines, VoIP connections use encryption and compression that are incompatible with the old faxing protocols.
Standard analog faxing uses the old T.30 faxing protocol, but to send document snapshots over IP networks you will need client devices that support the T.38 "Fax over IP" protocol. This can be done in two ways: Either the sending and receiving faxing devices (software or hardware) need to support T.38, or you need older T.30-only devices to send data to a T.30/T.38 gateway that will then relay the fax over an IP network to another T.38 device.
Modern fax machines may support the T.38 protocol, but it is also finding its way more and more into VoIP applications such as ZoIPer; however, as it currently stands the requirement for data translation makes sending faxes using T.38 protocols rather limited. For VoIP clients, faxes are generally sent client-to-client, so in the case of ZoIPer you cannot send a fax to any fax machine. Likewise, a local T.38 gateway requires another gateway on the receiving end for the transmission to work, which may not be implemented in the receiver's Fax setup.
Because of these limitations, the best option for VoIP faxing is if all the translation is done by the service itself. For instance, the popular Vonage VoIP service has a fax feature that can send faxes over their network to any fax machine, because they translate the fax data with their own T.30/T.38 gateways instead of relying on the client to have these gateways set up.
Besides just scanning and emailing a document to someone, there are a variety of online faxing services that will take a document and send it to a standard fax machine. Some of these are free, and others require a small fee for extra services or large faxes, but should be able to take documents in various formats and relay them to digital or analog fax machines. A few of these services are the following, though you can search for one by Googling "Internet fax" or some similar query:
Some of these services have desktop applications that let you send faxes from any document or application, instead of using a Web interface. Services such as Fossi let you use the system's standard print dialogue to send an Internet-based fax just as you would with a local fax modem.
Topher has been an avid Mac user for the past 10-15 years, and has been a contributing author to MacFixIt for just over a year now. One of his diehard passions has been troubleshooting Mac problems and making the best use of Macs and Apple hardware both for family and friends, as well as in the workplace. He and the newly formed MacFixIt team are hoping to bring enhanced and more personable content to our readers, and keep the MacFixIt community going here at CNET. If you have questions or comments for Topher or the other MacFixIt editors, feel free to contact us at http://www.macfixit.com/contactResources