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| Blacklisting of
websites & domains |
Central OPS maintains an up to date list
of the largest and most aggressive known
spammers. This list is maintained by both
Virus/Spyware/Spam Filter System and
other anti-spam groups. This list is
automatically updated. |
| Keyword
scanning of emails |
Scanning methods include a scoring
system such that emails are scored based on
a number of criteria. If the score is above
a threshold, then that email is flagged as
spam. |
| Checksum
technology |
Central OPS monitors email traffic
through the Internet and uses checksum
technology to keep track of the number of
times a particular message has appeared on
the Internet. If a message has appeared very
broadly, it would be categorized as known
spam. Checksums of known spam messages are
utilized by the Virus/Spyware/Spam Filter System |
| Message
authenticity checking |
Several algorithms are utilized to
verify the authenticity of a message. Some
of these are simple checks to verify that
the "from address" is authentic. Some are
more complex relating to SMTP protocol. |
| Rate controls |
Rate controls are utilized to stop
denial of service attacks as well as
dictionary based spam attacks. These are
integrated and automatic in the Virus/Spyware/Phishing Filter System. |
| Bayesian
Algorithms |
Bayesian filters are personalized to
each user and adapt automatically to changes
in spam. To determine the likelihood that an
email is spam, these filters use Bayesian
analysis to compare the words or phrases in
the email in question to the frequency of
the same words or phrases in the intended
recipient's previous emails (both legitimate
and spam). |
| Spam
Fingerprint Checking |
Fingerprinting techniques examine the
characteristics, or fingerprint, of emails
previously identified as spam and use this
information to identify the same or similar
email each time one is intercepted. These
real time fingerprint checks are
continuously updated by Central OPS and
provide a method of identifying spam with
nearly zero false positives. |
| Intention
Analysis |
Intention Analysis is used to look at
the objective or goal of the email. If the
objective of the email is to sell something,
try and have you click on a commercial link,
or get you to take a particular action that
is indicative spam, the email will be
categorized as spam |
| Dual Layer
Virus Blocking |
The Virus/Spyware/Phishing Filter System
uses two virus scanners to maximize
protection. This provides two layers for
extra safety. |
| Decompression
of Archives |
The Virus/Spyware/Spam Filter System
unpacks and examines every individual file
within 17 different types of archives. It
also uses techniques to examine password
protected archives. |
| File type
attachment blocking |
The Virus/Spyware/Spam Filter System
allows you to block certain types of files.
Many of the commonly blocked file types,
frequently contain viruses, such as VB
script (.vbs files). These blocking methods
have become industry standard in order to
provide additional protection. |
