[Alupis]

> HTTPS would be great but we don't transmit any personal data so it's not a high priority right now.

You are sending people's orders around the web. I'd consider that "personal".

None-the-less, use SSL, there is little reason not to use it these days. And as others have pointed out, it's the only good and easy way to guarantee what you send to one of these printers is what it actually received (no carrier tampering of your packets, etc).

Just use SSL.

[philh]

If SSL isn't supported by the Arduino chipset, then that sounds like more than a "little" reason not to use it. That sounds like it might be an "it would be a whole lot of work" reason not to use it.

(I don't actually know how much work would be involved, but goleksiak says they would really like to use it, so I assume it's not trivial.)

[angersock]

SSL on the Arduino--usually a little 8-bit (!) chip--is a bit resource intensive, in both memory and processing time.