Spam Blockers

Be sure to download our Spam Solutions White Paper...

Complete coverage of the spam problem and how best to get rid of it without interfering with your regular email delivery.

The Spam Solutions White Paper covers three excellent solutions each in spam filters, spam blockers, and spam appliances.

Download your copy here: Spam Solutions

It's a PDF file, so left click the link above with your mouse and choose the "Save As" option.

Otherwise, it will open in your browser window.

Get going with your anti-spam solution today.


Spam Blockers

A spam blocker system prevents the delivery of spam to your PC or network by blocking spam before email is received. Email is routed through a remote system which analyzes the messages and diverts a high percentage of the incoming spam.

The primary advantage of this approach is a higher level of protection against virus and malware attachments since they are not allowed to reach the network or user level. Similarly, offensive messages are also disposed of without any exposure risks.

The spam analysis rules are controlled by the spam blocking company.

Three popular solutions are available from:

• MailControl Spam
• Brightmail
• Postini


MailControl Spam

MailControl Spam from BlackSpider Technologies is a fully managed service designed to provide companies with the highest level of protection at a cost effective price.

This adaptive approach combined with the ability to set spam thresholds on a domain and per-user basis, ensure that MailControl Spam is the most effective spam filtering technology on the market today.

The whole scanning process takes just a few seconds. Once each message has been analyzed by the different tests, the message receives an overall 'spam score'.

The score is then compared against the spam threshold defined by the customer; mail scoring below the configured threshold is delivered as normal, whilst mail scoring above is quarantined as spam.

The MailControl Spam service works by processing e-mail through a number of filters, which include:

• Black and White Lists
• Adaptive Spam Engine
• Real Time Black Lists
• Lexical Analysis
• Bayesian Probability
• Distributed Checksum Clearinghouse
• Collaborative Spam Databases
• Spam Traps
• Trend Analysis

Managing Spam
Spam thresholds can be configured at a domain level and at a user level. This approach enables administrators to 'tune' the threshold for users who receive a significant amount of spam.

E-mail messages classified as spam can be dealt with in a number of ways. Most customers choose to quarantine the e-mail automatically and send a daily or weekly report to the intended recipient listing the messages which were blocked and providing a link back to the portal where the message can be viewed and released if required.

Alternatively a customer may elect to receive spam, but have it highlighted by a comment in the subject line. e.g. 'Spam:'

In summary, MailControl Spam controls the flood of unwanted e-mail messages, increasing employee productivity, return on assets and reducing costs.

More information is available at




Brightmail’s spam blocking solution is available as an appliance or as server-based software. It’s used by six of the top ten ISP’s and, as a result, filters approximately 10% of all email. While not inexpensive, it is a high-quality solution.

Catches the Most Spam
Brightmail's complete spam defense leverages a cocktail of effective technologies, a huge spam detection network, and a real-time rule delivery mechanism.

• Six separate technologies target different types of spam
• Proactive heuristic and machine learning technologies trap evolving spam
• Patented spam signatures stop real-time spam attacks
• Dynamic list of open proxy servers identifies & locks out known senders of spam
• Intelligent filters identify foreign language spam

Highest Accuracy
False positives (messages incorrectly identified as spam) cause users to lose faith in spam blocking. From day one, Brightmail has had an unwavering commitment to protecting legitimate mail. Many Brightmail customers feel comfortable deleting spam without review.

• Automated and manual safeguards
• Support for false positive submissions
• Review (by a Brightmail technician) of every false positive
• Corrected rules deployed globally within minutes
• Only introduces a new technology after it has passed rigorous accuracy standards

Zero Administration
Many anti-spam solutions place even more burden on administrators. Immediately effective out-of-the box and constantly updated, Brightmail doesn't require any tuning or training of filters by administrators.

• 24/7/365 protection from new spam attacks
• Automatic, timely, secure updates
• New filters available every 10 minutes
• Global anti-spam operations centers in the US, Ireland and Australia
• Real time visibility of new spam trends
• No ongoing tuning or training of filters

More information is available at




Postini’s spam blocking service utilizes an intermediate step in email delivery, passing all incoming and outgoing mail through Postini’s data center.

Postini™ services secure and manage email systems, without the need for software or hardware. Using patent-pending pass-through technology (versus store-and-forward methods), email bound for a company's email server is processed in real-time through a highly secure service architecture.

Within milliseconds, Postini's award-winning email security solution separates spam and viruses from legitimate messages. Legitimate email is instantly passed on to the destination mail server. Suspicious email can either be quarantined in a web-based, password-protected message center for administrator or end-user review, or tagged and delivered. The entire process is fully automated — valid emails pass through and cannot be physically accessed by any persons other than the recipient.

Postini™ now offers Perimeter Manager Enterprise Edition, our flagship email security service. Enterprise Edition is the next-generation in email security, utilizing revolutionary patent pending technology including Postini Industry Heuristics™, outbound and policy management, and integrated disaster recovery services. Enterprise Edition comes with the industry's best service commitment – a 99.999% service level agreement, and now also includes full 24/7 customer support.

With Enterprise Edition, you can:

• Block malicious or unwanted email messages before they penetrate the corporate firewall, improving employee productivity, minimizing IT management and maintenance costs, saving bandwidth, server and disk capacity, while keeping security threats away from the network.

• Maximize email filter accuracy and minimize false positives with patent-pending Postini Industry Heuristics™, industry and function specific heuristics-based analysis technology that enables the creation of content filters specific to industries and functions such as law and financial services, and from 'trusted networks' of senders based on proprietary Postini knowledge of SMTP content and transport patterns in these industries.

• Filter outbound email and implement policy controls with full-duplex security and content-management tools, giving IT administrators the tools to lock down and protect all aspects of the corporate email system. Filter all outgoing email communications for viruses and other policy violations.

• Maintain and protect the integrity of the enterprise email infrastructure with an integrated disaster recovery service. If your email server ever goes offline due to a break in network connectivity, or server malfunction or overload, Postini will step in seamlessly and redirect all incoming email to a secure, architecturally redundant message store at the Postini data centers until connectivity is restored.

• Enhance productivity by providing end-users with an html-based Quarantine Summary Report. This report eliminates the need to log-in and review messages in the Postini Message Center.

• Gain exceptional management and system-level control over your email infrastructure to ensure the highest levels of trust, reliability, flexibility and security. Postini's extensive reporting and management capabilities allow email system administrators to monitor the Postini service and their entire email infrastructure in real-time, regardless of server platform or system topology.

More information is available at


Visit our Net Sense™ Customer Help Center 
for network tips, useful info, tools, resources and FAQs!

Consulting Articles ] Consulting Services ] Client Help Center ] Code Of Ethics ] Code Of Ethics ] Consulting Services ] Articles ] Code Of Ethics ] New Pages ]

Spam Legal Issues ] Spam Appliances ] [ Spam Blockers ] Spam Filters ] Free Spam Filter ] Spam Solutions ] Antivirus Best Prac. ] Spam Prevention ]

Back Up Next  


Net Sense © 2004



Spam Legal Issues
Spam Appliances
Spam Blockers
Spam Filters
Free Spam Filter
Spam Solutions
Antivirus Best Prac.
Spam Prevention