200 likes | 308 Vues
Learn about internet spying, how it works, and ways to protect your information. Discover tools like IP audits, cookies, and cache memory to safeguard your online privacy.
E N D
Spying and security on the Internet Some tricks to know
Are we spied on on the internet? • What kind of information on my computer can be found by other people? • Why is that possible? • How it works ?
Summary • 1/ Am I spied on ? • 2/ IP Audit • 3/ Cookies • 4/ Cache memory
AM I SPIED ON WHILE SURFING ? THAT IS THE QUESTION…
-YES YOU ARE !!! -No, I can’t believe it !!
-You want a demo baby ? -Yes, I do…
http://www.cnil.fr/index.php?id=123 • Is that enough ? Or do you want more ?
Give me your IP and I’ll tell you who you are… • http://visualtracking.symantec.com/vt_main.asp?langid=fr&go=
One more time with more pieces of information… • http://www.ripe.net/whois?form_type=simple&full_query_string=&searchtext=&do_search=Search • http://www.xpenguin.com/plot.php?address= • http://www.elfqrin.com/binfo.shtml
How it works ? • TCP/IP: virtual networks • Need connection and identification • Requests have pieces of information: • @ of webpage + • Information on your computer : REMOTE_HOST = REMOTE_ADDR = 160.228.152.6HTTP_USER_AGENT = Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1)HTTP_REFERER = http://www.cnil.fr/index.php?id=95 -a CGI (Common Gateway Interface) script analyse this data: REMOTE_HOST et REMOTE_ADDR gives your DNS and IP -HTTP_USER_AGENT gives pieces of information of your browser -HTTP_REFERER gives protocols, access-ways, pages, images etc.
IP audits • Client/servers/requests • The server needs your IP to send you what you asked for • The @IP is find thanks to DNS server • DNS=Domain name->@IP • The paquets contain: 1/ @IP of the computer which sent the packet, 2/ @IP of the computer to which it is sent.
Nothing hampers the computer to create a file with your @IP, your DNS, the date, the hour and the file. • You are not « aware » of this recording • It is called « audit-files » • Concerning the CNIL, they have a CGI script that gathers and analyses the audit-file of their servers
C O O K I E S • What is it ? • A file on your disk • Content : Data you have once given (voluntarily or not) • Ex : a login, the number of accesses to the site, your favourite beer…
C O O K I E S • How does it work ? • An instruction in the page : • Set-Cookie : Name=value; expires=date; path=chemin, domain=nom_domain; secure • Information re-sent to the server each time you visit the page • Can I block them ? • Yes… see the options of your browser
C O O K I E S • Advantages • to save some useful data (Ex.: login, preferences…) • transparent use • Disadvantages • On your pc only s.o else’s cookies… / Lost data • Content not readable • Negative use : linked to your name / e-mail address • advertising,…
CACHE MEMORY • What is it ? • Files saved • on your pc • on a proxy • Content : Files which are downloaded when you look at a page (ex: images…)
CACHE MEMORY • How does it work ? • Files loaded are saved in the cache memory • When needed, the file is loaded from • the cache memory, if it is present • otherwise: downloaded • faster • Can I block it ? • On your pc : Yes… see the options of your browser • On the proxy : No… unless you don”t use one
CACHE MEMORY • Advantage • faster • Disadvantage • one can see what pages you visited
Conclusion • There are plenty of ways to find data on people on the internet. There are ways to hamper them, but nobody can really surf without being able to be found…