10-06-2017, 07:14 AM
Definition
It can take days to send mail across the country and weeks to go around the world. That is why now a day ordinary letter posting is referred to as 'snail mail'. So, what is e-mail? In its simplest form, email is an electronic message sent from one computer to another. We can send or receive personal and business- related messages with attachments like pictures or other documents. Its fast, it's easy to use and it's cheaper than postal route. Those messages which are sending to us will reside in our mail inbox.
Sometimes, having an e-mail account can be very frustrating. People will fill our mail with advertisements, forwarded messages, product details, business offers, and all sort of unwanted junk. Separating the messages that we really want from the hundreds of unwanted mails is a daunting task. It may include both unsolicited and solicited mails. Those unsolicited mails are referred to as Spam mails. This process called Spamming makes many people really hate e-mail. But you are not powerless in the fight against unsolicited e-mail.
For this reasons filters are introduced. Mail filters in the server filters the Spam mails before they reach our inbox and mark them as Spam mails and it is send to our bulk folder. So we are prevented from reading those mails. If we use to respond for those mails more and more Spam mails will be sending to our inbox by the Spammers. When the sender of unsolicited e-mail offers to remove our e-mail id from their list, don't fall for it. This just confirms that our e-mail account is active, and we may actually receive more Spam. We can also do one thing, i.e. to send a message to our ISP or online service that we received unsolicited mail and to provide the originating address. In most cases, the return addresses are phony, but the service provider may be able to take action to stop the Spam.
Many of the e-mail clients have special filters designed to block Spam. One among the best Spam filtering software is Spam Assassin, which is an Apache Software Foundation project and is released under the Apache License. The Apache Software Foundation provides organizational, legal, and financial support for a broad range of open source software projects. Spam Assassin is a mature, widely-deployed open source project that serves as a mail filter to identify Spam. It is an intelligent email filter which uses a diverse range of tests to identify unsolicited bulk email, more commonly known as Spam. These tests are applied to email headers and content to classify email using advanced statistical methods. In addition, Spam Assassin has a modular architecture that allows other technologies to be quickly wielded against Spam and is designed for easy integration into virtually any email system.
Spam Assassin is a mail filter installed on our mail servers to identify Spam. It checks for Spam using a large number of pre-set rules that check the header, body, and sender of all email messages sent to your domain mailbox. When an email fails enough of these rules, it will be flagged as potential Spam and sent on to our inbox as an email attachment. We will usually be able to determine if the email is junk or not by reading the Spam Assassin information included with the original email - all without having to open the attachment. Spam Assassin uses a variety of mechanisms including header and text analysis, Bayesian filtering, DNS blacklists, and collaborative filtering databases. Spam Assassin runs on a server, and filters Spam before it reaches our mailbox.
Spam Assassin is a nice program designed for ISP mail servers that immediately rejects incoming Spam before it ever gets anywhere near our inbox. Spam Assassin is written in perl. It requires a recent version of Perl to be installed on the local machine. It depends on many modules and Perl packages, and may be effected if Perl is upgraded on the machine. We may not be able to use it if we do not have rights to install Perl. If we don't have rights to install Perl on the target machine, we can't use Spam Assassin.
Spamming is the abuse of electronic messaging systems to send unsolicited, undesired bulk messages. While the most widely recognized form of Spam is e-mail Spam, the term is applied to similar abuses in other media: instant messaging Spam, Usenet newsgroup Spam, Web search engine Spam, Spam in blogs, and mobile phone messaging Spam. Spamming is economically viable because advertisers have no operating costs beyond the management of their mailing lists, and it is difficult to hold senders accountable for their mass mailings. Because the barrier to entry is so low, Spammers are numerous, and the volume of unsolicited mail has become very high. The costs, such as lost productivity and fraud, are borne by the public and by Internet service providers, which add extra capacity to cope with the deluge. Spamming is widely reviled, and has been the subject of legislation in many jurisdictions. Spamming has also been used as a denial of service ("DoS") tactic, particularly on Usenet. By overwhelming the readers of a newsgroup with an inordinate number of nonsense messages, legitimate messages and computing resources can be erased