OREANDA-NEWS. September 01, 2011. Kaspersky Lab, a leading developer of secure content and threat management solutions, has announced that it has been granted a new patent in the USA. Patent № 8,001,195 covers a highly effective method for identifying spam in the text of email messages using lexical vectors. This method, developed by Kaspersky Lab, significantly reduces the time required for detection of spam when a large database of known unsolicited messages is used. This makes the technology especially useful for large-scale email service providers, which filter huge amounts of spam messages every hour, reported the press-centre of Kaspersky Lab.

The method of creating a lexical vector is much more efficient than traditional technologies for spam detection - including filtering by keywords, blocking addresses of bulk email senders, etc. The patented method is made up of several steps for analyzing an email. First, the message’s text is normalized morphologically (lemmatization) in order to identify unique words and their variations. Every unique word, except noise words (prepositions, articles, various forms of common verbs like to do, have, be, etc.), is assigned an identifier based on the number of occurrences in the message text. Based on all identifiers assigned a lexical vector is formed. Next, a histogram of the lexical vector is generated while at the same time the length of the lexical vector is calculated separately.

In order to detect spam, the resulting histogram and lexical vector length can be compared with the histograms and vector lengths of lexical vectors corresponding to known spam texts stored in the database. The patented technology thus provides a much faster scanning speed than the traditional method of direct checking of message contents against a large database.

The patent for Kaspersky Lab’s anti-spam technology is the company’s 31st in the USA, while a further 46 patents are pending and currently being examined by the United States Patent and Trademark Office. Furthermore, patent offices in Russia, China and the European Union are currently examining around 80 Kaspersky Lab patent applications relating to a range of unique IT security technologies.