Increase Efficiency with Intelligent Email Traffic Control

Written by CipherTrust

Continued from page 1

Innovation fromrepparttar Leader in Messaging Security

Connection Control features several proprietary technologies working together to help IronMail providerepparttar 109511 fastest throughput inrepparttar 109512 industry:

  • Dynamic Connection Rejection – Limitsrepparttar 109513 number of messages that reach IronMail and rejectsrepparttar 109514 resources available torepparttar 109515 offending IP address.
  • Rejection Intervals – By relying on data gathered byrepparttar 109516 IronMail Global Network, CipherTrust research has determinedrepparttar 109517 optimal intervals to reject and allow connections.
  • Anomaly Detection Engine – Examines and controls overall traffic flow for IronMail to identify threats.
  • Threat Response Updates –repparttar 109518 IronMail Global Network comprises over 2500 IronMail units inrepparttar 109519 field. The system provides data and updates to IronMail units as needed.
  • TrustedSource™ - CipherTrust’s reputation service maintains data on millions of e-mail senders globally and provides real-time information to IronMail appliances about a sender’s e-mail sending behavior.

Proven inrepparttar 109520 Field

Currently in use at enterprises such as Cox Communications, Inc. (NYSE: COX), Connection Control dynamically rejects upwards of 50 percent of connection attempts from known spammers with dramatic results. But don’t just take our word for it. Franklin Warlick, Cox Communications’ messaging systems administrator, saw instant results when he installed Connection Control on Cox’s IronMail units, which protect approximately 60,000 inboxes. “CipherTrust’s Connection Control saved us valuable time and resources when we really needed them. This new technology in IronMail allows us to laser in onrepparttar 109521 worst offenders, and reject their spamming attempts atrepparttar 109522 network edge. With Connection Control, Cox Communications was able to reject 90,000 spam messages an hour immediately, giving us great bang forrepparttar 109523 buck from a product that already paid for itself many times over.”

Takerepparttar 109524 Next Step

Learn more about how IronMail helps organizations stoprepparttar 109525 spam flood and fight back against spammers by visiting or requesting CipherTrust’s free whitepaper, “Stoppingrepparttar 109526 Spam Flood with IronMail Connection Control.

CipherTrust is the leader in anti-spam and email security. Learn more by downloading our free whitepaper, “Stopping the Spam Flood with IronMail Connection Control” or by visiting

How Spammers Fool Spam Filters

Written by CipherTrust

Continued from page 1

Bayesian Filters

Named after Thomas Bayes, an English mathematician, Bayesian Logic is used in decision making and inferential statistics. Bayesian Filers maintain a database of known spam and ham, or legitimate e-mail. Oncerepparttar database is large enough,repparttar 109510 system ranksrepparttar 109511 words according torepparttar 109512 probability they will appear in a spam message.

Words more likely to appear in spam are given a high score (between 51 and 100), and words likely to appear in legitimate e-mail are given a low score (between 1 and 50). For example,repparttar 109513 words “free” and “sex” generally have values between 95 and 98, whereasrepparttar 109514 words “emphasis” or “disadvantage” may have a score between 1 and 4.

Commonly used words such as “the” and “that”, and words new torepparttar 109515 Bayesian filters are given a neutral score between 40 and 50 and would not be used inrepparttar 109516 system’s algorithm.

Whenrepparttar 109517 system receives an e-mail, it breaksrepparttar 109518 message down into tokens, or words with values assigned to them. The system utilizesrepparttar 109519 tokens with scores onrepparttar 109520 high and low end ofrepparttar 109521 range and develops a score forrepparttar 109522 e-mail as a whole. Ifrepparttar 109523 e-mail has more spam tokens than ham tokens,repparttar 109524 e-mail will have a high spam score. The e-mail administrator determines a threshold scorerepparttar 109525 system uses to allow e-mail to pass through to users.

Bayesian filters are effective at filtering spam and minimizing false positives. Because they adapt and learn based on user feedback, Bayesian Filers produce better results as they are used within an organization over time.

Bayesian filters are not, however, foolproof. Spammers have learned which words Bayesian Filters consider spammy and have developed ways to insert non-spammy words into e-mails to lowerrepparttar 109526 message’s overall spam score. By adding in paragraphs of text from novels or news stories, spammers can diluterepparttar 109527 effects of high-ranking words. Text insertion has also caused normally legitimate words that are found in novels or news stories to have an inflated spam score. This may potentially render Bayesian filters less effective over time.

Another approach spammers use to fool Bayesian filters is to create less spammy e-mails. For example, a spammer may send an e-mail containing onlyrepparttar 109528 phrase, “Here’srepparttar 109529 link…”. This approach can neutralizerepparttar 109530 spam score and entice users to click on a link to a Web site containingrepparttar 109531 spammer’s message. To block this type of spam,repparttar 109532 filter would have to be designed to followrepparttar 109533 link and scanrepparttar 109534 content ofrepparttar 109535 Web site users are asked to visit. This type of filtering is not currently employed by Bayesian filters because it would be prohibitively expensive in terms of server resources and could potentially be used as a method of launching denial of service attacks against commercial servers.

As with all single-method spam filtering methodologies, Bayesian filters are effective against certain techniques spammers use to fool spam filters, but are not a magic bullet to solvingrepparttar 109536 spam problem. Bayesian filters are most effective when combined with other methods of spam detection.

The Solution

When used alone, each anti-spam technique has been systematically overcome by spammers. Grandiose plans to ridrepparttar 109537 world of spam, such as like charging a penny for each e-mail received or forcing servers to solve mathematical problems before delivering e-mail, have been proposed with few results. These schemes are not realistic and would require a large percentage ofrepparttar 109538 population to adoptrepparttar 109539 same spam eradication method in order to be effective.

Working alone, each individual spam-blocking technique works with varying degrees of effectiveness and is susceptible to a certain number of false positives. Fortunately,repparttar 109540 solution is already at hand. IronMail®,repparttar 109541 secure e-mail gateway appliance from CipherTrust®, provides a highly accurate solution by correlatingrepparttar 109542 results of single-detection techniques with its industry-leading correlation engine,repparttar 109543 Spam Profiler™.

Learn more about stopping spam by requesting CipherTrust’s free whitepaper, “Controlling Spam: The IronMail Way”.

The core of IronMail’s spam capabilities,repparttar 109544 Spam Profiler analyzes, inspects and scores e-mail on over one thousand different message characteristics. Each method is weighed based on historical accuracy rates and analysis by CipherTrust’s experienced research team.

Optimizingrepparttar 109545 Spam Profiler requires precise calibration and testing thousands of combinations of values associated with various message characteristics. To automate this process, CipherTrust developed Genetic Optimization™, an advanced analysis technique that replicates cutting-edge DNA matching models. Genetic Optimization identifiesrepparttar 109546 best possible combination of values for all characteristics examined byrepparttar 109547 Spam Profiler and automatically tunesrepparttar 109548 IronMail appliance, reducing administrator intervention and assuring optimum protection against spam and spam-born threats.

Take The Next Step

Learn more about how IronMail can secure enterprise e-mail systems by visiting or requesting CipherTrust’s free whitepaper, “Controlling Spam: The IronMail Way”. This resource will providerepparttar 109549 information you need to make an informed decision about eliminating spam and securing your e-mail systems.

CipherTrust is the leader in anti-spam and email security. Learn more by downloading our free whitepaper, “Controlling Spam: The IronMail Way” or by visiting

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