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The Greylisting approach

Greylisting is a relatively old concept and is well understood by many including spammers. But we take it to a totally different level by adding a lot more clever techniques that ensure that the spammer cannot get past us without significant effort on his part.

Let us see how we achieve that in detail below.

Anyway as a bonus this also stops all sorts of irritating malware like viruses, Trojans, worms and other annoyances.

Spam control is really not that hard if you understand how spammers do their job.

There is a lot of difference between the way spammers send out mail and the way legitimate mailers send.

Spam sending botnets (which are programs) send out e-mails in bulk. And their business is really dependent on volume. Even if one person in a million clicks on a p0rn site or is stupid enough to opt for some pleasure enhancement pill or some such thing they are fine.

This is precisely what we use for controlling spam by using OpenBSD greylisting.

Here are some even more interesting features.

No false positives at all since this technique does not differentiate between e-mails, only senders
Spammers actually get hurt by this. So if everyone used OpenBSD greylisting then spammers would go out of business.
Since greylisting pushes back mail to the spammer, we do not accept spam even at an MTA level. This means that your bandwidth bills and storage space is saved.

E-mail sending is a two way process involving the sender and the receiver. The sender cannot send faster than the receiver says he can receive. It is this fact that we exploit in order to hurt spammers.

We create a tarpit for the spammer's botnet such that they get stuck in sending. They never get to deliver the mail and we keep wasting the spammer's resources. This is how we hurt spammers. Legitimate senders don't bother since they have only one mail to send.

The fact that we do not allow the spam to even enter our network saves us the trouble that the spammer intended to cause. And since we never read a single line of e-mail content there is no way we can ever wrongly classify a legitimate mail as spam.

We keep track of spam sender IP addresses and also refer to trusted up-to-date global databases for spamming botnets for tarpitting.

Our strategy of not reading mail content speeds up legitimate mail processing unlike content scanning/statistical filtering solutions.

Every human generated mail message (including mailing list mails) are ham. So there is no question of the subjectivity of what we call spam.

This device does one job and does it well. It does only spam control and does it well. It can handle a very high mail traffic due to the absence of content scanning. In addition to being itself capable of handling heavy load due to the intrinsic design and spam control technique, it can also scale and provide load balancing/failover using a protocol by name CARP. This comes in handy should you have hardware/software failure.

The company is also committed to providing the best technical support possible since all our products are aimed at 'plug in it, let it go' model.

Which is to say that it will require zero maintenance or baby sitting on your part. This is in contrast with content scanning based spam filtering solutions that are the order of the day that not only slow down your legitimate mail but also leads to false positives. You no longer have to sit and scan quarantined mails to decide whether to bounce, delete or accept your mail.

There are other reasons why we think our technology is a real breakthrough.

There is no idea of false positives in our technology
It does not slow down legitimate mail traffic
Since it stops spam even before it gets a chance to get into the network, it saves you precious bandwidth and storage space
Spammers actually get hurt by this, so if more people used our technology then there would be less spam on the Internet to deal with
This technique can also be used to minimize viruses, worms and other malwares that float on the Internet in a transient fashion

Up: Technology behind SpamCheetah spam Previous: The software side Contents