Anti Spam

Anti-spam refers to any hardware, software, or process used to prevent unsolicited, junk, or bulk e-mail, also known as "spam", from entering an e-mail system. Anti-spam techniques are often embedded in various software products and services. Although many anti-spam solutions are extremely effective, no anti- spam product or service offers a complete solution to preventing spam issues, as each has strengths and weaknesses, especially in the rejection of legitimate e-mails, the non-rejection of spam, and the cost and time associated with each solution.

The various implementation methods of anti-spam solutions can be broken into four categories:

• Individual action required
• Automated through administrator
• Automated by sender
• Employed by researchers and law enforcement

Spam filters use various methods in order to detect spam, some of these methods include:

• Detecting spam based on the content or key words within an email message.
• Collecting a list of sites which are known IP addresses of spammers, open relays, zombie spammers, etc.
• Detection of bulk or unsolicited email.

There are also many techniques end-users can use in order to reduce or prevent spam. Some of these techniques include:

• Discretion - Only share email addresses among a small group. Members of this group can not disclose any email address beyond the designated group.
• Address munging - Alter an email addresses in a way to avoid email address harvesting yet allows legitimate users to figure out the correct email address.
• Avoid responding to spam - Any response to a spam email alerts the spammer of a valid email address.
• Use contact forms on your website to detract spam - Contact forms allow communication without exposing the email address or the recipient.
• Disable HTML - HTML functionality can contain web bugs which allow spammers to detect valid email addresses and alert them when an email has been caught in a spam filter. Spammers can also use JavaScript to direct the user to webpage's containing spam messages and make the pages being viewed difficult to exit from.

E-mail Administrators use a wide array of appliances, services and software in order to reduce spam. Some systems and techniques used include:

Authentication and reputation, Challenge/response systems, checksum-based filtering, country-based filtering, DNS-based blacklists, Enforcing RFC standards, greeting delay, greylisting, HELO/EHLO checking, Invalid pipelining, nolisting, quit detection, honeypots, hybrid filtering, outbound spam protection, pattern detection, PTR/Reverse DNS checks, rule-based filtering, sender supported white lists, SMTP proxy, spamtrapping, statistical content filtering, tarpits, background checks on new users and customers, confirmed opt-in mailing lists, rate-limiting, spam report feedback loops, and many others.

SOFTWARE AS A SERVICE (SaaS)

Software as a Service (SaaS) is a software that is deployed over the internet and/or is deployed to run behind a firewall in your local area network through a distribution model in which applications are hosted by a vendor or service provider. SaaS can be implemented with local applications that expire after a certain time, but it is ideally suited for cloud computing in the Internet and Web browser-based applications, which can run in any desktop or mobile device, no matter the operating system. In this model, the applications are maintained in the service provider's datacenter, and every time users launch their browsers and log on, they get the latest version. In addition, the data can also be stored in the provider's datacenter. SaaS is one of the fastest growing segments of the information technology (IT) industry because it provides a more cost-effective alternative for enterprises to achieve their business objectives than traditional packaged applications.