E-Mail Security-Anti Spam

Spamming refers to the use of an electronic messaging system to send unsolicited messages especially advertising messages to a group of recipients. Unsolicited messages mean the recipient did not grant permission for those messages to be sent.

Anti-spam refers to the use of any software, hardware or process to block spam from entering a system. The anti-spam software uses a set of protocols to determine unsolicited and unwanted messages and prevent those messages from getting to a user’s inbox.

Most of the Anti-spam solutions that are available today can be customized as per your needs, allowing only the approved emails into your inbox. Such software always presumes that all the incoming emails are spam, and only allow those, from the people you know, to come in.

An email anti-spam service is a service that complements an existing email filter in order to increase its spam detection rates. Typically, a standard email filter detects around 97% of spam emails, increasing to a spam detection rate of around 99% when acceptable spam thresholds are adjusted upwards.

However, in some larger businesses, a spam detection rate of 99% is insufficient to prevent the business from continuing to receive a considerable volume of spam. As 1% of spam emails that avoid detection are likely those with the highest level of sophistication, they are also those with the highest threat level.

Furthermore, by raising acceptable spam thresholds too high, genuine emails can be quarantined as spam (false positives), delaying the delivery of business-critical communications. An email anti-spam service with a high spam detection rate can resolve this issue without causing unreasonable delays.

How an Email Anti Spam Service Achieves a High Detection Rate

An email anti-spam service has many of the tools commonly found in existing mail filters. These include RBL and SURBL filters, recipient verification and Bayesian analysis (the tool that rates the level of spam in each email for the purposes of blocking it or allowing it subject to the acceptable spam threshold).

Whereas RBL and SURBL filters are good at detecting emails from known sources of spam, if a spammer uses a different server with a different IP address, the filters are ineffective. By comparison, an email anti-spam service has a greylisting function to detect emails from previously unknown sources of spam.

The way the greylisting function works is to decline every inbound email. The email is returned to its originating server with a request for it to be resent. Normally, the email will be returned within a few minutes unless the originating server is too busy to respond to the request. In most cases, spammers′ mail servers are too busy sending more spam emails to respond and the spam email is never returned.

Along with the greylisting function, an email anti-spam service employs antivirus software, the Sender Policy Framework protocol, and HELO tests to minimize the volume of spam a business receives. By using these tools in conjunction with the tools commonly found in existing mail filters, an email anti-spam service can achieve a spam detection rate in excess of 99.9% – often with no false positives.

What is Anti-spam and Benefits of Using Antispam Software?

• Blocking Spam
• Quarantining Spam
• Automatic Filter Updates
• Monitoring Multiple Accounts
• Your Personal Whitelist
• Reporting Spam

Let us look at some of the benefits and features of the anti-spam software:

Blocking Spam

Certain anti-spam solutions not only block specific email addresses but also search for subject lines and text in the email messages. You can customize it to block incoming emails based on senders, and even if your email address is not in the recipient field.

Quarantining Spam

Anti-spam filters automatically quarantine the spam emails, ensuring your inbox is spam-free. Such quarantined emails are held for a fixed number of days, say 30 days or so, and then dumped. During that period, you can check and recover any legitimate email that may have been quarantined.

Automatic Filter Updates

Most of the anti-virus software comes with an automatic filter update feature for the timely detection of new types of Malware threats. Automatic updates not only helps the anti-spam software to stay up-to-date, but it also helps secure your system from new kinds of Malware.

Monitoring Multiple Accounts

With this feature, you can monitor and filter spam from multiple accounts. You can filter your home email from work email, and vice versa.

Your Personal Whitelist

Some anti-spam software allows you to maintain a ‘friendly’ list of people whose emails you wish to accept. These emails will never be mistaken for spam as against the blacklist of spammers. You can also update the list in the future.

Reporting Spam

Some anti-spam programs allow you to report spam back to the company supplying the program. It helps the company to develop a new type of filter based on the analysis of the reported spam.

Emails have become a very popular way of advertising, and it is time that you start filtering your emails, to avoid spam. Most of the anti-spam solutions are signature-based that use their signature file (blacklist) to detect and respond to a new type of Malware.

In signature-based anti-spam software, new and unknown types of Malware goes undetected since there is a time gap between the time these new type of Malware threats are released and the time anti-spam software vendors have identified them and updated their signature file. This is where Containment technology comes into play.

Containment technology works by keeping the threats or harmful files under control or within certain limits. The harmful files are processed in a restricted operating system environment, thus controlling the resources and the spread of infection.