|
 |
dilluns, 23 / maig / 2005 |
Palau Reial Major, the residence of the counts of Barcelona from the 13th century. This tower is named after Marti the First, the last king before the castilian Trastamara's family took the office.
El Palau Reial Major, la residència dels comtes de Barcelona des del segle 13. Aquesta és la Torre anomenada de Martí I, el darrer rei abans de l’entrada de la família castellana Trastàmara.
|
17:19 (# Enllaç permanent) | Comentaris: | Trackback:
|
|
[Whitedust Security] Detecting Bayesian Filters. Gairebé tots els sistemes de detecció de correu brossa es basen en la utilització de filtres bayesians (veure Filtres bayesians per a identificar l'spam i Intel·ligència artificial per a lluitar contra l'spam), que aconsegueixen un elevat factor d'encert:
At this stage, it is almost difficult to find an anti spam product that doesn’t make use of Bayesian filtering. Over time Bayesian filtering has proved itself to be an almost cure for the spam epidemic, used both by open source solutions and commercial ones. While spammers have successfully found ways to circumvent most other filtering techniques, Bayesian filters remain an obstacle for the sending of unsolicited commercial email.
D'un temps a aquesta part, s'han trobat mecanismes per ignorar-los...
At present spammers attempt to thwart Bayesian filters by including random text or even long winded passages of literature in their spam email messages. This process of adding ‘neutral’ text to spam emails helps tip the balance and allow the message to be weighed as innocuous
Però la tècnica que sembla triomfar és escriure malament el text:
But here are the guts of this article. In order to successfully defeat Bayesian filters time and time again, spammers could make use of the following recipe. Some of the audience may have seen the following text in a commonly forwarded email.
Aoccdrnig to a rscheearch at Cmabrigde Uinervtisy, it deosn't mttaer in waht oredr the ltteers in a wrod are, the olny iprmoetnt tihng is taht the frist and lsat ltteer be at the rghit pclae. The rset can be a toatl mses and you can sitll raed it wouthit porbelm. Tihs is bcuseae the huamn mnid deos not raed ervey lteter by istlef, but the wrod as a wlohe.
(According to a researcher at Cambridge University, it doesn't matter in what order the letters in a word are, the only important thing is that the first and last letter be at the right place. The rest can be a total mess and you can still read it without problem. This is because the human mind does not read every letter by itself but the word as a whole.)
In reality the fact that words with jumbled up letters are still readable wasn’t discovered by a Cambridge University but rather by Graham Rawlinson which he detailed in his 1976 PhD thesis
While this technique of lettering jumbling doesn’t leave the text readable in all languages, it has been shown that text undergoing the same technique is readable in most European/Roman languages. Clearly any native English speaker will have no difficulty reading the above text, but obviously any attempt to categorize the text using Bayesian filtering would be extremely difficult.
|
17:04 (# Enllaç permanent) | Comentaris: | Trackback:
|
|
[ZDNet] Netscape fixes holes in 'security' browser. Poques hores després de publicar la versió 8.0, ja es`tava disponible la versió 8.0.1 que elimina 44 problemes de seguretat, molts dels quals ja feia temps que havien estat solucionats al codi font de Mozilla/Firefox.
The update notification on Netscape's Web site notes version 8.0.1 of Netscape "includes all Firefox security patches up to 1.0.4", and initially listed 44 security advisories. However the company later clarified this to say 41 of those advisories had been addressed in the initial 8.0 release of the browser.
Netscape's general manager Jeremy Liew said upon the browser's release that its key selling point was its security features.
"Security is the sizzle that will get people to use this new browser," Liew said. "I think the Web has become a more dangerous place. The threats of phishing and spyware have become more and more real."
|
16:52 (# Enllaç permanent) | Comentaris: | Trackback:
|
|
© Copyright 2003-2005 Xavier Caballe.  . Si no s'indica expressament el contrari, el material publicat en aquest weblog es distribueix d'acord amb la llicència Creative Commons. El contingut és responsabilitat única i exclusivament del seu autor i no té cap relació amb les seves activitats professionals.
|
 |
 |
 |
 |
Contingut actualitzat
Categories
Darrers comentaris
Arxiu
Contingut antic
(ja no s'actualitza)
Versions anteriors
d'aquesta pàgina
|
 |
 |
 |
 |
|
