Re: Controlling SPAM in the best way
Spam is one of the major pitfalls of the social web. Take a look at this …. 10 out of 12 email messages are spam and 1 in 39 emails contain a virus… whoof. As messaging and communication applications proliferate throughout the web, thousands of unwanted messages keep streaming in every day. Deciding on the best method of spam prevention on your blogs, forums, or even contact forms can be difficult.
- One method to fight SPAM can be to log the incoming message with the user's IP address and a timestamp of the post. Then, when a user attempts to post multiple comments, you can check to see if the user has posted more than once within a specified window of time, for example 40 or 50 seconds, or if the current was the last poster. This is not a fullproof method because spammers can use proxies too … also robots have ample of time to spam…
- Next method for fighting spam is to build a blacklist of common spam keywords and to disallow posts that contain the words. We can creatae a set of key words and check to see if an incoming string contains them. Spammers have evolved defenses against this method by posting variations of the words. They replace letters with numbers, symbols, and other such characters to create a broad selection of keyword variations.
- Also a most common spam protection technique on the web today is CAPTCHA Completely Automated Public Turing test to tell Computers and Humans Apart as given in Wiki. The technique is a useful tool for blocking robots that attempt to visit your site to post spam messages or create fake accounts with fake information. CAPTCHA tests can be audio files, but are more commonly images presenting a series of characters and numbers that you have to enter into a form which has been asked to be filled by the site you are visting. CAPTCHA works well for its intended use, but there are minor drawbacks. A CAPTCHA requires (yet another) field for users to fill in after entering usernames, passwords, and security questions. There is understandably an annoyance factor accompanying their use also users who are disabled can’t make use of the CAPTCHA fields.