Recommended FireFox Extensions

Here are some firefox extensions, which I recommend under MUST category

• NoScript : Allows you to control, sites which can execute java/flash or any other script. Best to have for security reasons.
• AdBlock Plus : Disables any advertisements on the webpages you visit. (includes blocking of flash adv)
• Gmail Notifier : If you are a gmail user, its very handy
• Split Browser : If you have a wide screen display ( like TFT display), this is a must, allows to you see multiple pages at same time.
• Google toolbar : If you have gmail account and if you are not using a public PC for browsing, this will help you to send any page (or selected content) through gmail. Includes bookmark button which can be accessed globally from any PC.
• Foxpose : If you are used to open so many TABs while browsing, this one helps you to show a window with preview of all tabs, easy to find any TAB. (also see Tab scope)

You can find these extensions through google or give a search here https://addons.mozilla.org/en-US/firefox/

Read more...

Quick download IEEE paper

Recently, IEEEXplorer has introduced a STAMP on when you download publications from the site. So everytime you click a link to download/open the pdf in the browser there is a IEEE image banner and the pdf in the bottom frame. Sometimes it has happens that the PDF does not open even after waiting for a long time. So here is a simple trick to download the pdf file.

For e.g : If the link that you are trying to open is :

http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&isnumber=&arnumber=823551

then just copy that address and paste in the terminal and REPLACE the PART as below

http://ieeexplore.ieee.org/stampPDF/getPDF.jsptp=&isnumber=&arnumber=823551

Now use 'wget' to download the file as mypaper.pdf.

[DONT FORGET THE QUOTES around the link] wget

"http://ieeexplore.ieee.org/stampPDF/getPDF.jsp?tp=&isnumber=&arnumber=823551" -O mypaper.pdf

For IWL users: It is assumed that wget recognizes your proxy settings (might be through cntlm/ntproxy). Else use konqueror to open the new link, konqueror can directly open/download the PDF.

Proxy-settings for konqueros is in "Tools-Configure Konqueror-Proxy"

Read more...

TinyURL and Internet Security

In the previous post we have seen uses of URL shortening service.

http://techqe.blogspot.com/2009/09/how-tinyurl-works.html

So what is the RISK !!

lets take an situation:

If you recieve an email from someone (forum, newsletters, company) telling you to click on link,if the site appears to be Chinese or Russian site you would'nt click on it write (bingo). And obvious if you have good Anti-virus installed, it will detect the links and warn you .

But, if email links point to TinyURL you are in no position to know the identity of the site, maybe it is hacked site or hacker's. And it is not possible for Anti-virus package to detect it.

Tinyurl isn't the only redirection service. Here is a list of sum od them's

• tinyurl.com
• bit.ly
• budurl.com
• eweri.com
• hex.io
• idek.net
• is.gd
• poprl.com
• snipr.com
• twurl.nl
• ub0.cc

This phenomenon has resulted in many URL shortening services.

Here's what I do or You should :

• Use a good anti-virus that scans web pages also.
• Be cautious of shortened URLs
• Use good web browser (Check the browsers hack list)
• And. Services provied by TinyURL like Preview feature

Read more...

How TinyURL work's !!

The service tinyurl accepts a long URL string (presumably the location of a web document or something else such) and creates a permanent shortcut for it.

http://techqe.blogspot.com/2009/06/sharing-keyboard-and-mouse-between-two.html

to

http://tinyurl.com/mzcmys

The question is, how does the service create such a small shortcut for any of the virtually thousands of web URLs out there? Does it compress the URL? Does it store it somewhere?

A little judicious observation can reveal some of the little "secrets" behind this service. The first "obvious fact" is that the shortcut has always a fixed length. In fact, the effective length looks as if it is exactly six (last 6 characters). The second "obvious fact" is that the shortcut consists of only small-caps letters and the digits 0-9.

The above observations quickly lead to the conclusion that the number of all possible configurations of the second part of the shortcut string is bounded above by 366 = (26 letters + 10 digits)6. This number equals 2176782336 and is close to maxlongint (or max int in Java).

Therefore, all one has to do to create such a service is have a Java program with the following (pseudo) declaration:

T=array[1..int] of string;

Considering the maximum length of any string allocated to be 255, an upper bound for the memory of this table will then be 2147483647 * 255 = 547608329985 bytes. That's roughly 510 Gigabytes of storage space and is doable with large capacity drives.

so, TinyURL variations are not limitless but they are close !!!

will have more posts regarding URL shortening services soon :)

Read more...