Spam Filters Explained

Written by Alan Hearnshaw

Continued from page 1

While this may seem like a good idea fromrepparttar outset, a whitelist methodology is too restrictive for most people and, as virtually all spam e-mails carry a forged “from” address, there is little point in collecting this address to ban it in future as it is very unlikely to berepparttar 105888 same next time. There are bodies onrepparttar 105889 internet that maintain a list of known “bad” sources of e-mail. Many filters today haverepparttar 105890 ability to query these servers to see ifrepparttar 105891 message they are looking at comes from a source identified by this Internet-based blacklist, or RBL. While being quite effective, they do tend to suffer from “false positives” where good messages are incorrectly identified as spam. This happens often with newsletters.

Challenge/Response Filters “Open sesame!”

Challenge/Response filters are characterised by their ability to automatically send a response to a previously unknown sender asking them to take some further action before their message will be delivered. This is often referred to as a "Turing Test" - named after a test devised by British mathematician Alan Turing to determine if machines could “think”.

Recent years have seenrepparttar 105892 appearance of some internet services which automatically perform this Challenge/Response function forrepparttar 105893 user and requirerepparttar 105894 sender of an e-mail to visit their web site to facilitaterepparttar 105895 receipt of their message.

Critics of this system claim it to be too drastic a measure and that it sends a message that "my time is more important than yours" torepparttar 105896 people trying to communicate with you.

For some low traffic e-mail users though, this system alone may be a perfectly acceptable method of completely eliminating spam from their inbox - one step aboverepparttar 105897 "Whitelist" system outlined above.

Community Filters “A united front”

These types of filters work onrepparttar 105898 principal of "communal knowledge" of spam. When a user receives a spam message, they simply mark it as such in their filter. This information is sent to a central server where a “fingerprint” ofrepparttar 105899 message is stored. After enough people have “voted” this message to be spam, then it is stopped from reaching allrepparttar 105900 other people inrepparttar 105901 community.

This type of filtering can prove to be quite effective, although it stands to reason that it can never be 100% effective as a few people have to receiverepparttar 105902 spam for it to be “flagged” inrepparttar 105903 first place. Just like its similar cousinrepparttar 105904 Internet black list (RBL), this system also can suffer from “false positives”, or messages incorrectly identified as spam.

Hopefully you are now armed with a little more information to be able to make an informed decision onrepparttar 105905 best spam filter for you. For further information, consider readingrepparttar 105906 reviews and articles found at

Alan Hearnshaw isrepparttar 105907 owner of, a web site which conducts weekly in-depth reviews of current spam filters, provides help and guidance inrepparttar 105908 fight against spam and provides a useful community forum.

Alan Hearnshaw is a computer programmer and the owner of, a site which provides weekly in-depth spam filter reviews, user help and guidance and a community forum.

Anti-Phishing Bill Introduced To Congress

Written by Richard A. Chapo

Continued from page 1

In April 2004,repparttar IRS warned consumers that scam artists were sending emails purportedly fromrepparttar 105887 IRS. Consumers received emails claiming they were under investigation for tax fraud and subject to prosecution. The emails contained language telling recipients they could “help”repparttar 105888 investigation by providing “real” information and directed them to a website that was derivative ofrepparttar 105889 IRS site. Consumers were then asked to provide detailed personal information to disputerepparttar 105890 charge. Since most people fear repparttar 105891 IRS, one can assume that a large number of people took repparttar 105892 phishing bait.


The Anti-Phishing Act of 2005 is a nice start to combating scam artists that use phishing to pilfer money from consumers. The Act, however, will not put an end to deceptive phishing practices if it is passed. There reason involves jurisdictional issues.

A large percentage ofrepparttar 105893 individuals promoting phishing scams reside outside ofrepparttar 105894 United States. While they may take notice ofrepparttar 105895 law, it will have no discernible effect on their fraudulent scams. Until there is an international response, phishing scams will continue to be a problem. Nonetheless, Senator Leahy should be commended for initiating efforts to deal with this growing problem.

Richard Chapo is the lead attorney for the law firm - a firm providing legal advice to California businesses. This article is for general education purposes and does not address every facet of the subject matter. Nothing in this article creates an attorney-client relationship.

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