Computer telephony: why wait?

The other day I had one of those living-in-the-future moments. An important phone call came in, but the colleague I needed to bring into the call wasn't available, and the caller couldn't wait. So, with the caller's permission, I recorded the call and forwarded it as an MP3 file to my colleague. When she later replayed the conversation, she got crucial points -- both factual and emotional -- that I never could have accurately reported.

VoIP fantasy come true? Not even close. The call came in on a POTS line. I answered on a regular -- not even cordless -- telephone. The integration between the voice and data networks was courtesy of JK Audio's QuickTap.


There are dozens of ways in which personal computers can add value to the PSTN. Caller ID screen pops, conference call setup, call logging, voice archiving, and user-programmable IVR (interactive voice response) are just some of the productivity aids that we should all take for granted by now -- but that almost nobody can.

The story of the Bellheads vs. the Netheads is a myth in the primary sense of that word. It explains a real conflict between worldviews in a way most people can easily understand, and that's useful. But we can't believe it literally. If the mammals keep waiting for the dinosaurs to die out, we'll keep missing chances to exploit them. [Full story at]
When you click through to the column, you'll see that its title -- as published online and in the print magazine -- uses the phrase "IP telephony," not "computer telephony" as originally written. I can understand why the change was made: the former term is more familiar than the latter. And that's exactly my point. We tend to assume that the integration of computers and telephones means both devices must use TCP/IP. That's an enabler, but not a requirement. There's a ton of useful integration you can do by bridging between TCP/IP and the PSTN.

Here's an variation of the example I gave in the column. Recently, while recording a phone conversation, I wanted to bring new participants into the call. On my end of the call, I used three-way calling to bring in another POTS line. On the other end of the call, my partner did the same. Using my Internet-attached computer, I can do all sorts of interesting things with the resulting MP3 file: filter it, edit it, email it, blog it. Just because your phone and computer don't use the same network for audio data doesn't mean your phone and computer can't be usefully combined.

Here's another example: Asterisk, the open source PBX for Linux. It supports various flavors of VoIP. But fundamentally, it's a PBX. You can use it simply to add intelligent control to your POTS lines, and that's just what some folks do.

VoIP is terrific, and it's the future. But that future isn't evenly distributed yet, and won't be for a while. In the meantime, let's not lose sight of the original sense of the phrase computer telephony. It's compatible with, but not necessarily the same as, IP telephony.

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