Okay, we've all gotten them... Somebody we know sends us an e-mail message that tells us that we need to forward this message to ten friends, or some kid is going to die, fail their science class, or a 600-pound gorilla is going to fall on you. On the other hand, if you do forward the e-mail message, then Bill Gates is going to send you a million dollars, or some wish will come true, or some kid's cancer will miraculously go into remission.
Now, I want you to stop and think about this for a moment. As a rational human being, can you think of any possible way that the act of sending an e-mail message could possibly alter the tides of reality to the point that any of the above may occur? "Of course not," you say, "but what's it going to hurt if I forward the message to a few of my friends?"
Well, I'm here to tell you that the answer is, quite simply: plenty.
(Warning to the technically inclined: major oversimplifications ahead!)
The Internet, as you probably know, is a massively intertwined network of networks. Each provider, or ISP, connects to other providers through any number of means, but generally speaking, there's some kind of copper, fiber-optic, or wireless link that allows providers to transfer information among themselves. In addition, there are trans-oceanic copper and fiber lines that handle intercontinental traffic, not to mention satellite links to more remote, and less developed areas. The amount of information that a provider can transfer over these lines in a given period of time is referred to as bandwidth. Major providers, like AOL, MCI, AT&T, and Sprint provide bandwidth to smaller, or regional providers, like EarthLink, and NetZero. In turn, the major providers will peer with other major providers to create the great big network we call The Internet. Without knowing it, when you surf to your favorite website, the traffic may pass through numerous providers in order to reach its destination.
Think of it like a great road system. You have the major providers, who build the freeways, and provide very large connector ramps to other freeways. Then, you have the regional providers, who build the major city streets, each of which is accessible via one (or more) offramps from the major providers. Finally, depending on your neighborhood, you might have another provider that connects to the major city streets to bring access to your particular neighborhood.
So, when you access your favorite website, the traffic has to "drive" out of your neighborhood, possibly find its way to a freeway, get off at the right offramp, and travel to the neighborhood of the web server you're accessing. Pretty amazing to think that all of this happens in a matter of milliseconds!
Anyway, each of the providers has to pay for the size of their "street," and, in particular, the size of the "onramps" to other providers. This can get rather expensive. A DS-3, which provides enough bandwidth for 15 active cable modem users, can start at $2,500 per month (as of July, 2004). Obviously, it wouldn't be cost-effective to get a DS-3 for every 15 customers that a cable modem provider has, so they may allocate that amount of bandwidth to 100 or more users, in an effort to defray costs. But, as users' bandwidth demands become greater, so shrinks the available bandwidth per user. As a result, the provider has to add more bandwidth, and this costs money.
"Fine," you say, "but what about my little e-mail message? That couldn't possibly take up much bandwidth."
Of course, your message doesn't require much bandwidth to send, but let's apply an economy of scale to your message, because, let's face it: you're not the only one doing this.
In an effort to save the life of some kid, you forward an e-mail message to 10 of your friends. Now, let's say that this e-mail message has 4,096 (4k) bytes of information, which, including all of the headers that travel with an e-mail message, is a very conservative number. You have now generated 44k of data that is to be transmitted across the Internet: 4k for your message to go to your ISP's mail server, and then 4k per copy for each of the recipients, as your ISP will distribute the message to your receipients' ISPs' mail servers. Now, each one of these people forwards the message to 10 of their friends, resulting in another 440k of information being sent. Five more generations down the road, that number has ballooned to over 40 gigabytes of information that's being transferred! Remember that $2,500-per-month DS-3 line? It would take over 3 hours just to send that data over the line! At a cost of $2,500 per month, that's over $10 in bandwidth costs.
But, it gets worse.
Remember how the Internet is a great big mesh of networks? Well, that bandwidth is most likely required of numerous ISPs, in order to transport the message from one place to another. Ship that data to a server in another country, and those costs really explode.
But wait, it doesn't end there...
So, now we have 40 gigabytes of data floating around the Internet. Well, that data has to be stored somewhere, before you log in to download it. On a midrange disk array, the cost of 40 gigabytes of storage is about $320, not to mention the cost of the additional computing hardware the ISPs have to purchase in order to handle millions of these messages per day. Somebody has to pay for that.
So, I'm not saying that you should never forward e-mail to people. Just practice discretion. Since the act of e-mail forwarding is simply a matter of a click, and a few keystrokes, it's easy to forget that there's a very real cost involved in transporting your message to your friend who's just going to delete it anyway. Additionally, most of the chain e-mail (and, by "most," I mean roughly 99.999%) is completely bogus. Fortunately, there are a number of resources that can help you determine if a message is legitimate, and worth forwarding.
If you receive an e-mail message from someone that urges you to forward it to others, then, chances are, you'll be able to find the message listed here, at which point you should break the chain, and just not forward it. Better yet, help to educate the person who sent you the message by sending them a link to this page, or any of the other excellent references mentioned above.