How can I send a fax from my Linux machine using a SIP connection? I don't have a modem.
Ideally, I'd like to provide a PDF or TIFF file, and send it via my SIP provider. Is this possible?
First, it is possible to do this a number of ways, but a word of caution. Fax and SIP do NOT work well together and I usually recommend my clients use a POTS line for fax whenever possible.
That said, the easiest way to fax over sip is to connect a Linksys SPA 3102 or PAP2 to your SIP server network. Then you can use a standard fax machine as an analog device to fax over the SIP connection. This way can, and often does, generate echo on the line such that you may have difficulty sending the fax and need to resend it a few times.
If you create a TIFF or PDF it would be significantly easier to email it than to fax it.
You can try to use hylafax if you have a modem that is not a WinModem. I was never able to get it to work well which is why I used the PAP2 as above.