What are the Different Types of Anti-Spam Services?

Email spam, also known as junk mail, is unsolicited email that is broadcast in bulk to numerous recipients. Spam messages typically contain advertisements for pharmaceutical and financial products or links to commercial and adult web sites. Some messages, however, can contain computer viruses or other types of malware. Although it is virtually impossible to stop spam, many products are now available that offer anti-spam services, such as hosted anti-spam services, disposable email services, and challenge/response services.

With hosted anti-spam services, a third-party service provider has access to the user’s email account and filters the incoming mail. The service provider allows legitimate mail to enter the user’s inbox but sends potential spam mail to a separate folder. These services can be hosted on either the service provider’s network or on the customer’s network.

Disposable email address services allow users to create unique email addresses for each of their contacts. Users can either access their mail from a central location offered by the service provider, or they can have their mail forwarded to a different email address of their choice. This option does not necessarily stop spam, but it can identify which contact is sending spam so that users can respond accordingly.

Challenge and response services allow email from known email addresses to enter the user’s inbox. For unknown email addresses, however, the service replies to the email and asks the sender to complete a task to verify his or her email address. The sender may be asked to click a link, answer a question, type what can be seen in an image or some other simple task. Once a sender verifies his or her address, the service provider adds that email address to the list of known addresses.

In addition to these third-party services, most email providers offer some combination of anti-spam services. Using spam filtering, the email providers separate suspected spam from legitimate email and place the suspect mail into a spam folder. Users can then review the messages in that folder to ensure that the spam filter did not exclude legitimate emails. These email providers also allow users to mark email in their inbox as spam, which helps refine the filtering process.

These anti-spam services can be effective at spam protection, but users should also take spam prevention measures. Providing an email address to a limited number of people will reduce the amount of spam a person receives. Users should avoid responding to spam, including requests to be removed from the mailing list. Legitimate organizations will honor the removal request, but spammers may send more spam, since they now know that the email address is valid.