Fax Declines Slowly, But FoIP Grows

Fax? Who are we kidding? Today, most business documents are transferred electronically (e-mail, shared access to a server, FTP, etc.). Nonetheless, fax remains in use in some industries, e.g. finance and health. There’s some confusion as to why. I’ve had fax product managers tell me fax is required by HIPAA, the Health Insurance Portability and Accountability Act, or by another specific law. No.

Fax remains in use because our court systems’ rules of evidence say a “duplicate” is admissible to the same extent as an original unless a genuine question is raised as to its authenticity. Duplicates include fax copies (at least as traditional fax is understood). Electronic records, on the other hand, are only admissible if their trustworthiness is established in court. It’s that extra burden of proof that makes e-mailed PDF files burdensome while TIFF files sent over T.30 protocol, i.e. faxes, are OK. As an engineer, I regard this as nuts, but as a citizen it’s just as well our court procedures evolve slowly. In any event, while the total fax market is shrinking, fax-over-IP markets are growing.

Traditional fax machines rely on modems that were designed for analog phone lines and traditional digital trunks (like T1/E1). These suffer with packet loss and other issues associated with today’s VoIP and circuits-over-packet technology. Thus when the corporate PBX (News - Alert) moves to VoIP, fax machines still need analog lines or must be replaced. Adding SIP trunks means finding a new fax solution.

The industry answer was T.38, a protocol for passing both TIFF files and T.30 signaling over an IP link. Unfortunately, T.38 was developed before everyone realized the full impact of network address translation. On the telephone network, fax is an end-to-end transaction – direct dialed, phone number-to-phone number. With the Internet, T.38-capable devices are blocked from connecting by the lack of routable Internet addresses. NAT boxes handle address translation for http and e-mail, but don’t recognize T.38. As a result, many enterprises use T.38 to communicate with a local fax server that has dedicated T1/E1 access or special arrangements that support T.38.

Alternately, the whole problem is outsourced to an e-fax service provider. Then you typically exchange PDF files with your e-fax provider, which sends or receives them using T.38. If a legal question arises, your e-fax provider must testify as to what it sent (or received) and when.

Meanwhile, since fax doesn’t work well over VoIP trunks, the accelerating adoption of VoIP is driving growth in FoIP services. Of course this can’t last forever, but there is no comparable single standard for electronic documents likely to become ubiquitous in the near term, so fax will be with us for many years. IT

Brough Turner (News - Alert) is co-founder of Ashtonbrooke Corp. (http://ashtonbrooke.com), a startup involved in wireless infrastructure.

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