Spam Wars - Who's Side is Your Provider On?
Spam is unwanted junk mail that comes in various forms. The most common form is in email and if your host provider battles the unwanted mail, this is something that will benefit you in the end.The different kinds of spam are numerous. Many people do not realize it, but anything bulk sent, such as jokes and family pictures, can be considered spam. However, this type of spam is acceptable because the pictures are cute and breathtaking and the jokes make us laugh. However, the commercial spam, the porn pictures, the fake lottery winnings, and other such emails are very unwelcome, and these are the ones you want to avoid getting.
Off site spam filters are always updating their databases with IP addresses. Users are continually sending them forwarded spam, loaded with the IP addresses of spammers. However, spammers have expanded how they are sending junk messages to the public. Hand held devices such as mobile phones and palm pilots are now targets of spam. They are also sending spam through chats, games, blogs, newsgroups, and search engines. And you can still find spam through the fax machine.
Hosting sites generally provide email addresses with your website. However, you need to find out if they provide spam and virus protection. You should not have to install filters for the sites contact email addresses. A hosting company can offer a variety of server level solutions to protect their users. Three main techniques are:
- Local Blacklist Filters
- Keywords and Regular Expressions
- Bayesian Filters
Keyword filters are more effective than blacklisting. They look for particular strings of keywords. If those keywords are present in the email, it rejects it. Some filters try to use regular expressions to build a sophisticated rule to prevent spam from reaching your inbox. Regular expressions are syntax rules to identify strings of numbers or text.
Bayesian interferences are the most sophisticated and effective method to preventing spam. This method takes a large data set compiled from previous spam messages, and scans the emails. If they do not contain any of the data the filter seeks, it is sent to your inbox. Services that offer this type of filtering prevent billions of spam from reaching inboxes.
Sending spam violates most Acceptable Use Policy (AUP) of ISPs. However, providers may be limited in their ability or willingness to enforce their AUP because they do not want to lose profitable customers. In addition, the United States has made sending spam legal, as long as it has some specific content such as a truthful subject line, correct information in the headers and email address, postal address of the sender in a conspicuous spot, and more minor requirements. If it does not contain any of this information, it is considered illegal. Also, aggravated or accelerated penalties will apply if the spammer harvested the email addresses from somewhere. This is against terms of service (TOS) of many sites, including Yahoo!, Hotmail, and GMail.
Detecting spam by email content is extremely popular. However it can be an inaccurate way to filter your emails. If you set a filter for "Viagra," it can be most effective against the senders of those spam. However, if your friend sends you a joke in an email that mentions "Viagra," it will get listed as spam. Also, spammers are starting to use numbers in place of letters like "I". Spelling words like "v1agra" will bypass the filter and end up in your inbox.
DNS-blackhole lists (DNSBL) contains lists of known IP addresses of spammers, open relays, zombie spammers, and more. Spamtraps are full of email addresses that were never valid or have been invalid for a lengthy period of time and are now used to collect spam. Enforcing Simple Mail Transfer Protocol (SMTP) can be used to block email that does not comply with the standards of the RFC. Many spammers use poorly created software or do not comply with the standards because they do not have legal control of the computer sending the spam (zombie spam.) By setting standards on the Mail Transfer Agent (MTA), the mail administrator can reduce the spam considerably. In other situations, simply obtaining a fully qualified domain name (FQDN) in the SMTP's EHLO (extended hello) can block up to 25% of spam. Small organizations will remove their MX (Mail eXchange) record and have their A-Record point to their SMTP. RFC standards require a secondary server for their A-Record when their MX server fails. This method does run the risk of losing legitimate email, however it has been known to reduce spam by 75%.
Internet users and system administrators use a vast array of tactics to remove, deflect, and eliminate spam. System administrators have begun to use the services of spam filters such as Postini, AppSoftware, Brightmail, and SpamAssassin to filter their users' email accounts and eliminate the amount of spam that they download. This has proven effective for most email users, however there is always the few that slip through.
Spammers have started to use anonymous email addresses such as Hotmail to send spam to countless users of email. They use webbots to create the email addresses as they require countless numbers of them in order to avoid detection and capture. In an effort to cut down on the abuse of free webmail, a device called captcha, a series of letters and numbers in a graphic that users must decipher and correctly copy, has been created. Blind users can receive audio help for this device. As such, spammers have found a way to get around that particular roadblock.
New measures will be invented to prevent spam as the spammers defeat every roadblock that is put in their way. This seems to be a problem that will never go away, despite the measures that are continually being taken.