Seum said:
I remember many years ago when I looked into encryption briefly and it
wasn't as complicated as you suggest. It was a matter of using a
password to decrypt the message.
I was focused on the fax *protocol* in how the scanned image is
transmitted and received (and how that data can be intercepted by any
other fax-compliant device). Sounds like you're thinking of where the
fax protocol is overlaid with a file transfer by having the binary
content (scanned image) represent a file rather than an image. For
example, you can transfer a password-encrypted .pdf file via fax
protocol but obviously you need to have the software/hardware to perform
that feat and so does the recipient of your fax. Similarly, there is
fax-to-email transfer protocol T.37 where a fax is sent that represents
an e-mail (converted from a TIFF image), delivered by e-mail, and can
thusly incorporate encryption as defined by e-mail standards (the e-mail
would be encrypted then converted to TIFF to send as image via fax and
decoded back to the hashed e-mail that can be decrypted with a password)
- but you're still using fax to transmit an image. You're using the
telephony network for file transfer. With the addition of FOIP, faxing
just seems even more stupid in converting a document for faxing over IP
to decode back on reception instead of using IP file transfer protocols
in the first place.
In most cases where the recipient demands receiving a fax copy of a
document has to do with the legality of the signature. Despite that
both faxes and e-mails are electronically transferred documents, the
laws in some countries recognize signatures as legal for faxes (despite
the electronic document can easily be modified) but don't see signatures
as legal in e-mailed documents. Gov'ts aren't expected to be up to date
and they often stick with staid technologies. They don't like
blackwalls so you turn your tire around to show the whitewall side.
Still the same tire but you've placated the uneducated requirements of
the viewer.
The OP wants to fax over IP (FOIP) but have the recipient at a telephone
number which likely means the recipient is on a telephony network. That
means a POP (point of presence) is needed at a telco to convert from IP
network to telephony. There are services that have these POPs. Some
are paid services, some are free. I've seen eFax, a paid provider,
offer the encryption service to their customers but the recipient also
must support encrypted faxes (so it's really a business service). You
send them a file via IP that they convert to a TIFF image to then send
over their IP-to-telephony POP to the telephone number of the
recipient). Obviously they're getting your file (before it gets
converted by them). They have to be able to scan that file so obviously
it cannot be encrypted. For paid services, they may be able to simply
convert the binary for the file into a scrambled looking TIFF and send
that but I haven't seen that as a free service (plus the recipient would
need to be able to handle the conversion of TIFFs to the original file
format).
Do you have an example of a free FOIP provider that includes encryption
for no charge? I'd like to know and probably others, too. Plus I'd
like to know how the recipient is going to automatically know the TIFF
they receive in a fax represents the binary contents of a file instead
of an image and what the recipient must install (software or hardware)
to do the conversion. I'm not sure that a simple TIFF-to-PDF converter
is going to work, especially for an encrypted file carried inside the
TIFF, but there might be something that works.
