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1 4/26/2010 [email protected]

Safer browsing

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Page 1: Safer browsing

14/26/2010

[email protected]

Page 2: Safer browsing

Web Browser is a software that is installed on your

computer. It is used to locate and display web

pages and other online content. Behind the scene,

a browser performs lot of functions but its key role

is to take your request to the web server and bring

the content to you and display it.

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Finds the web server

Takes your request and transports data

Transports cookies

Brings back content

Processes the content and renders it

Executes scripts (code)

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Enter a URL into a browser◦ Breaks the URL into a host + path Asks a DNS server for an IP address for the host

DNS server returns a IP address for that host

◦ Browser sends a request to the IP address Path is used to determine what file to obtain

Data for web server to process, maintain state

Server replies to the request – HTML, PDF, mp3, etc.

◦ Browser reads the HTML file and asks for all the files referenced in the original HTML file These additional files could be images, more HTML, or other types on content.

Additional files could reside on different hosts requiring more DNS requests

After browser gets all the pieces, it processes the data and renders a single “page”

Non-HTML file are opened in the browser of associated application.

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Internet Explorer (Microsoft)

Firefox

Safari

Chrome

Opera

Konqueror

Several others

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Data set by the web site owner

Data you enter in the form

Information you request

Cookies

Operating System, browser type

Your IP address – can help determine your

geographical location

Referring page

Much more

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Example URLs: ◦ http://www.somesite.com

◦ https://www.somesite.com

http – data is unencrypted while transport from the web

browser to the web server

https – data is encrypted while transported from the

browser to the web server

Make sure that data you don’t want anyone to eavesdrop is

encrypted – https in the address bar; closed lock in the

status bar

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Use one browser for your “important” surfing and another for “casual” browsing. That way data from one can't leak to the other (generally speaking)

Always keep an eye on the URL in the address bar

Read, Pause before clicking on anything Logout and always close the browser window Nothing is “really” free. Only download

files from websites you trust

Don’t open attachments forwarded from your friend’s computer is corrupted

Logout and close browser/tab The browser’s back and refresh features can be used to steal

passwords from insecurely written applications.

Be careful of Google search results Always type URL for sites where confidential information is in use.

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Always use the red “X”

in the corner of a pop-up

screen

Never click “yes,”

“accept” or even “cancel”,

because it could be a trick

that installs software on

your PC

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An Internet firewall

is like a moat

around a castle,

creating a barrier

between

your computer and

the Internet

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Search results may contain malicious web site

Does it make sense?

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Keep passwords private and create ones that are

hard to “crack”

Use password checker (See resources)

Never share your passwords with friends or be

tricked into giving them away

Do not email login name and password together

Do not text message your login information

If you do have to write, keep the paper in safe

keeping

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Avoid creating passwords using◦ Dictionary words in any language.

Words in all languages are vulnerable

Words spelled backwards, common misspellings, and

abbreviations

◦ Sequences or repeated characters.

Examples: 12345678, 222222, abcdefg, or adjacent letters

on your keyboard (qwerty)

◦ Personal information.

Your name, birthday, driver's license, passport number, or

similar information

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