Understanding the Basics
How Instant Messaging Works
By Erica D. Rowell 
N E W Y O R K, Jan. 12 — Instant Messaging is on the fast track to becoming the latest killer app for Internet technology.
A cross between e-mail, Internet chats and beepers — with a smidgen of Napster and telephone technology thrown in — an instant messaging program lets you exchange text messages with people using the same program. At least, that was its traditional calling.
These days, IM programs are adding more bells and whistles that allow you to trade files such as MP3s, the popular format for digital music, with your "buddies. Some let you send voice messages. And others can even communicate with competitors’ programs — despite some efforts by industry heavyweights to block this.
An Open Question
For the most part, though, IM programs don't work with their competitors' programs. So if you have the popular AOL IM, or AIM, while your best friend has Yahoo! Messenger, the two of you can't talk IM to each other unless one of you gets the other's service.
While this wouldn't be convenient, it's not difficult either; for now, at least, instant messaging programs are downloadable for free. But as the technology advances, the lack of cross-platform communication could be problematic, setting an anti-competitive stage.
This is one reason the Federal Communications Commission, in its role as a communications regulator, stipulated that AOL open its instant messaging service in approving the AOL-Time Warner merger.
Imagine being unable to call a Verizon user from your Nextel phone, or being unable to e-mail your Qualcomm Eudora software to someone using the Microsoft Outlook program.
Real-Time Conversation Piece
About half of the online population dips into IM mode once a week, up about 13 percent from the previous year, estimates Cambridge, Mass.-based Forrester Research. In an age where speed is everything, the beautiful thing about instant messaging is regardless of how fast — or slow — your modem is, IMing is virtually immediate. It's not as real-time as a phone conversation, but it leaves e-mail in the dust.
Instant messages are fast in part because they know who's available at any given moment to chat. So, unlike with e-mail and voice mail, you can't leave an instant message in an IM in-box — that would pretty much defeat the point of its moniker, anyway. As soon as you sign onto an IM service, the software tells the instant messaging server you're logged on and ready to receive messages. If you're not logged on, you can't get messages, period.
Once on the network, you can also send messages to almost anyone using the same service you have, as long as they happen to be logged on too. Different programs let you customize how to deal with incoming messages, so there are ways to monitor privately or even block unwanted queries, without letting the sender know you're available.
The text travels through the Internet through typical data packets, which are individual, numbered chunks of a file sent through the network in pieces and reassembled at the recipient end. But the route these packets take is more akin to the peer-to-peer technology that lets Napster users trade music files with each other or to chat network technology that lets a group of users in chat rooms "talk" with each other through typed words.
E-mail vs. IM: Which Is Safer?
A commonly held misconception about instant messaging is it is somehow more secure or private than e-mail; it's less likely to show your hand if you're typing things you'd prefer be kept between you and your recipient.
After Bill Gates' own e-mail was used him in the Microsoft antitrust trial, people started to get an inkling of just how open the Internet infrastructure is. And as the idea of e-mail being like a postcard started to catch on, rumors about practicing safe messaging through IMing began to abound. But these rumors are ill-founded.