Spying and security on the Internet

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Spying and security on the Internet

• Some tricks to know

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• 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 ?

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Summary

• 1/ Am I spied on ?
• 2/ IP Audit
• 3/ Cookies
• 4/ Cache memory

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AM I SPIED ON WHILE SURFING ?
THAT IS THE QUESTION
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-YES YOU ARE !!!

• -No, I cant believe it !!

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-You want a demo baby ?

• -Yes, I do

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http//www.cnil.fr/index.php?id123

• Is that enough ? Or do you want more ?

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Give me your IP and Ill tell you who you are

• http//visualtracking.symantec.com/vt_main.asp?lan
  gidfrgo

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One more time with more pieces of information

• http//www.ripe.net/whois?form_typesimplefull_qu
  ery_stringsearchtextdo_searchSearch
• http//www.xpenguin.com/plot.php?address
• http//www.elfqrin.com/binfo.shtml

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How it works ?

• TCP/IP virtual networks
• Need connection and identification
• Requests have pieces of information
• _at_ 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?i
  d95
• -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.

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IP audits

• Client/servers/requests
• The server needs your IP to send you what you
  asked for
• The _at_IP is find thanks to DNS server
• DNSDomain name-gt_at_IP
• The paquets contain 1/ _at_IP of the computer which
  sent the packet, 2/ _at_IP of the computer to which
  it is sent.

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• Nothing hampers the computer to create a file
  with your _at_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

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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

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C O O K I E S

• How does it work ?
• An instruction in the page
• Set-Cookie Namevalue expiresdate
  pathchemin, domainnom_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

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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 elses cookies / Lost
  data
• Content not readable
• Negative use linked to your name / e-mail
  address
• ? advertising,

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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)

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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 dont use one

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CACHE MEMORY

• Advantage
• faster

• Disadvantage
• one can see what pages you visited

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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