In Search of the Best Way to Fight Spam
Almost everyone with an e-mail account has experienced unsolicited commercial e-mail, or ’spam’ - and everyone knows how irritating it can be. Every day we can read about new breakthroughs in anti-spam technology, or another successful prosecution against spam senders located in the United States and Europe.
| The most surprising thing about spam, and what has kept it plaguing our e-mail accounts for years now, is that it invariably makes money for its senders. A Radicati-Mirapoint study this year found that almost one third of e-mail users have clicked a link in an unsolicited commercial e-mail for more information, and nearly one in ten have gone on to purchase a product as a result. |
The running rate for sending around a million spam e-mails now is around US$200. Given that most spam senders are hawking high margin get-rich-quick or impossibly hopeful lose-weight-quick schemes, it takes less than a 0.01% “hit rate” to make a lot of money.
Regardless of how successful spam is for the senders, the fact is that most users dislike it, and want it to stop. The fight against spam, from the user’s point of view, revolves around two solutions: server side and client side filtering. Each has unique advantages and disadvantages.
Server side filtering works from a central server, usually connected to several spam ‘blacklists’ (these lists identify known spam senders) and also analyzes each e-mail based on its individual characteristics. The ability to pool knowledge from analysis of millions of messages can help the accuracy of these systems. The “Report Spam” button on your web mail service is a good example of how spam is eliminated democratically.
Another benefit of server side filtering is traffic economy. When spam messages are caught before they are received, users and service providers do not pay for their delivery. However, server side filtering is not perfect. There is the real threat of “false positives” - genuine e-mails from friends or colleagues identified as spam, and not delivered as a result. Server filters often can’t deliver suspected spam to a special folder that you can look through later. Some servers can also be overzealous in their blacklisting techniques, and block whole Internet Service Providers (ISPs) while a spam outbreak is happening. Every user might find himself unable to send legitimate e-mail and the recipients usually aren’t aware that their e-mail provider, or ISP, is using spam technology that blocks the sender.
Finally, server side filtering can lack the ability to approve certain kinds of e-mails (like newsletters from companies in which you’re interested). You might make a purchase at an online shop and never receive the receipt, lost forever in a spam filter.
Main advantages of server filtering:
- Traffic economy through interception of messages earlier in the delivery chain;
- Spam filtering is based on the analysis of many messages hitting many server users at once, potentially increasing accuracy.
Spam is annoying, but being unable to send an e-mail to a loved one because it’s wrongly identified as spam is much worse. Even though most of our e-mail will pass through a server spam filter somewhere on its journey, server filters suffer from a need to be over-cautious about designating a message as spam, lest this decision be incorrect.
Therein lies the benefit of client side filtering. This technology works in a similar way as described above, except that the work is done by a program on the user’s own PC. Client filters usually depend less on blacklists and more on sophisticated detection methods that search through each e-mail. It’s usually possible to customize the strength of the spam filter, and approve or disapprove of specific senders and domains, be they relatives, friends or industry newsletters. Client filters also deliver spam to special e-mail folders that a user can browse through every so often, to check if any mail has been misidentified.
Main advantages of client filtering:
- Most programs include a folder containing messages thought to be spam, to prevent loss of your messages;
- Wide range of personal settings, such as which senders will always be delivered, which sites may not send you e-mail, and how strong you want your spam filtering to be;
- You are in control of your own spam filtering.
The challenges for all spam filters, no matter what the technology, are huge. For example, on the client side, the better our spam filter gets, the less we tend to check our spam folders, thus increasing the risk of false positives.
| The kind of spam filter technology you choose depends on how much real e-mail you are willing to miss in exchange for less spam. If you’re willing to let some real mail get lost for the sake of getting no spam, server filtering may be the better option. If all your mail is essential, choose a client side filter with an easy-to-use spam folder. Experience shows that there is no single way, and no winning formula, to stop spam yet. Of the forty billion e-mails estimated to be sent each day, around half are spam. The fight gets bigger each day. All the same, a combination of technologies, such as those found in modern client side filters, can help keep you spam free. |
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