I wager this is a toss-up. I guess they are equal since an e-fax is not a real fax. Is that about the size of it?
E-fax is more secure, since it’s bitmap data that isn’t readable without decoding.
Good to know. Thanks!
When you say e-fax what do you mean?
Do you mean a fax modem in your computer dialing the phone and sending a fax to somebody else’s computer’s fax modem or real live fax machine? Or do you mean one of those online services where you send them the fax via website or some other method and they in turn send it to the recipient’s fax modem or fax machine?
No common form of email nor e-fax is secure in the sense of being encrypted. So you’re really just hoping for adequate security by sufficient obscurity. Plus lack of snoopers in the plumbing between here and there.
I’d agree with folks above that in today’s world there’s less likelihood of snoopers tracking faxes. Sorta like there’s fewer viruses on Mac. It’s not so much a matter that Macs are more secure, but that there’s not the volume of users to make writing malware for them as lucrative. Today emails outnumber faxes a million to one; anyone trawling for gold is gonna look to emails.
All that thought is out the window if you’re sending these e-faxes to someplace that bad guys would have reason to know receives faxes that contain valuable information. If they know that, they can easily camp out there and read all the faxes. Likewise if they know you send out faxes containing valuable info. They’ll just camp out at your place and read all your outgoing faxes.
It’s all really just a matter of sufficient obscurity. Only you can asses “sufficient” for your needs.
When you’re asking whether something is secure, you should probably specify your threat model. From whom are you trying to secure the data?
But, both of those seem very unsecure. Maybe not quite equally unsecure, but knowing which one of them is more secure might not really be a useful distinction, since there are few threats that fit into the small gap.
Get 7-Zip and compress+encrypt your file using AES. Send the file and the password through different means (email + phone, for example).