When compared to analog faxing, is eFax secure?
I have recently come out of a meeting with a VoIP sales agent. He mentioned that we would receive eFax with the phones which is, in his words, “…more secure then analog faxing” when I asked him, how it was more secure he mentioned that one of his co-workers was able to access all the data on an analog line within minutes and see everything on the network.
So I mentioned SSL encryption, and it would obviously be possible to see the data if you man-in-the-middle the network with a rogue access point.
However I am not entirely sure if it is possible to encrypt faxes or not. So my question is, why is eFax more secure than analog fax (regular faxing) and what security measures can you take to encrypt faxes?
Your question - Is eFax secure can be answered as - Fax over VoIP (which is normally what eFax means) is not any more secure than Fax over pure analog lines. To clarify, eFax isn't a technical term, it's a marketing term. The underlying Fax is still an inherently analog technology, and the VoIP technology underlying it is merely trying to emulate the analog lines. Normally the other end of the call is often going to be an analog line connected to the PSTN.
Furthermore, the VoIP portion of the call isn't encrypted, is sent over unencrypted RTP and hopefully T.38 and can pass through multiple carriers before arriving at the destination. There's no reason to think tapping these lines is any more secure than tapping an analog line. Wireshark has nice tools to intercept this traffic if you have a place to sniff. Without using some sort of proprietary technology on both the sender and receiver, it's not possible to encrypt Fax. If you're concerned about someone intercepting the transmission, the short answer is don't use Fax, use some form of digital communication that's encrypted.