Technology

How does the iPod touch detect your location?

If you are the proud owner of an iPod touch, you would have noticed that the Google maps application on it identifies your current location with scary preciseness. Every wonder, how the touch manages to do that without a GPS or cellular receiver? Apparently, Apple uses a service from a company called Skyhook Wireless to do this. And how does Skyhook achieve this? They drive around in vehicles scanning for wi-fi signals and create a database that matches the SSID and MAC Address with the physical address. Put on your tin hats folks!! 🙂

Some interesting links

Apple’s use of Skyhook : http://www.skyhookwireless.com/inaction/apple.php

How Skyhook does it : http://www.skyhookwireless.com/howitworks/wps.php

December 2, 2008 by Mac Networking Rantings Technology Uncategorized 0

HOW TO : Recover deleted SSL certs from IIS

Here’s the situation.. you installed SSL cert on a website in IIS. You think you don’t need that site anymore and delete the site from IIS. The moment you delete it, you bite your tounge and remember that you are supposed to back up the SSL cert for future purposes.. But since the site has been deleted from IIS, you cannot export the key from the IIS manager!!.

Thx to Microsoft’s oversight (or potentially by design), you can still recover the certificate from the server.. Here’s how

  1. Open a MMC console by typing “mmc” in the Start –> Run prompt
  2. In the MMC console, click on File -> Add/Remove Snap-in
  3. In the “Add/Remove Snap-in” window, click on Add
  4. Choose the “certificate” snap-on and click on Add.
  5. Choose Computer Account in the certificate snap-on window and click on Next.
  6. Choose “Local Computer” (Note : If you want to recover from a remote computer, you can put in the UNC path. But you need to have admin rights on that machine) and click on Finish.
  7. Click on close and go back to the MMC console
  8. You will see all the certificates installed on the server
  9. Expand the “personal certificates” folder and you will see the SSL certificate from the website you deleted from IIS. Follow standard steps to export the certificate.
November 23, 2008 by HOWTO Technology Uncategorized Windows 5

HOW TO : Sync files using FTP

If you ever run into a situation, where you need to sync two different directories and need to do that in a batch mode, try using FTPSync.

FTPSync is a freeware tool written by Kristof Gajsek. The tool has a bunch of options, like being able to operate in GUI and batch mode. Also good automated sync capabilities.

Only limitation is that it is windows based.

November 14, 2008 by HOWTO Technology Uncategorized Windows 0

Free PDF editor

There are tons of free tools to create PDFs. Some of the ones I use on a regular basis are

  1. PDFCreator (http://sourceforge.net/projects/pdfcreator/)
  2. PDF addon for Microsoft 2007 (http://www.microsoft.com/downloads/details.aspx?FamilyId=F1FC413C-6D89-4F15-991B-63B07BA5F2E5&displaylang=en)
  3. PDF save option in OpenOffice (http://www.openoffice.org)

Now.. thx to the good folks at Sun, you can edit PDF files too for free now. Although this is not full fledged PDF editing, you can make simple text changes and move blocks of texts around.

You can get a free PDF editor solution by

  1. Download OpenOffice 3.0 at http://www.openoffice.org
  2. Download the PDF Import Extension at http://extensions.services.openoffice.org/project/pdfimport
  3. Install OpenOffice (pretty simple click next process)
  4. Install the PDF Import extension, by launching OpenOffice and adding the extension by going to Tool -> Extension Manager in the file menu
  5. Open a PDF file, edit, save and enjoy.

Love Open Source :-)..

October 30, 2008 by Technology Uncategorized 1

HOW TO : Clear saved username/passwords in Windows

I came to know this method, when I saw one of the IT techs use it to troubleshoot some Internet connectivity issues.

To clear any saved username/passwords (i.e. Internet Explorer, Windows Explorer etc) in Microsoft Windows, do the following

  • Click Start –> Run, and type in control keymgr.dll
  • Delete any entries you want to from the list
  • Click on close

I tried this on Windows XP and Vista.

August 13, 2008 by HOWTO Technology Uncategorized Windows 0

HOW TO : Configure JBoss to follow symbolic links

Jboss, in addition to being an application server also serves static content. We recently ran into an issue where some static content was not displayed when users hit the link. The JBoss server kept spewing 404 errors, stating that the content was not found. On some hair pulling research, we figured out that JBoss, like Apache, does not follow/allow content mapped to a symbolic link.

So for example in your web app, you added a sym link to another directory, where most of your content is stored, Jboss would not show the content, when you go to the link.

Here’s a quick guide to fix this.

  1. Go to the deploy folder of the context you want to configure. For example, if you used the default context, you go to $JBOSS_HOME/server/default/deploy/jboss-web.deployer
  2. Edit the context.xml file and add allowLinking=”true” in the Context (NOTE : This allows Jboss to publish symbolic links on all apps in your application server, if you want to restrict it to just one particular app, you have to edit the context.xml in your specific application folder). Upon adding the option, our context.xml file looked as such



   

   
   org.jboss.web.tomcat.security.RunAsListener

More information on options for the context.xml can be found here

http://www.jboss.org/file-access/default/members/jbossweb/freezone/docs/2.1.0/config/context.html

For the record, Jboss configuration and accompanying documentation is what I call black magic :).. Too many options, too many ways to do the same thing.

July 25, 2008 by HOWTO Linux Programming Technology Uncategorized Web 3

HOW TO : Disable annoying message in e-mail by AVG anti-virus

If you are using the free version of AVG Anti-virus by AVG Technologies (Formerly GRISoft), you might have noticed an annoying message that the software inserts in all the e-mails it checks.. The message looks like this

No virus found in this incoming message.

Checked by AVG – http://www.avg.com

Version: 8.0.138 / Virus Database: 270.5.4/1567 – Release Date: 7/22/2008 4:05 PM

I really appreciate the free service that AVG provides for home users, but I don’t want to be reminded or advertise to the world regd the anti-virus I use in every e-mail.

You can disable this message by doing the following in AVG 8.0

  • Open the AVG control panel
  • Click on Tools -> Advanced Settings in the file menu
  • Highlight the “E-mail Scanner” selection in the left hand pane and uncheck the “Certify e-mail” option for both the incoming and outgoing e-mail. Here’s a screen shot.

July 23, 2008 by HOWTO Technology Uncategorized Windows 0

Week 6 training and improved charts with Google Charts

Week 6 of the Chicago marathon training and I was again not able to keep up with my mid week runs. Although I did manage to improve the charts displaying the training program :).. I added a new column to compare my actual milege to the recommended milege.

Here are the parameters I used

cht=bvg
chs=400×250
chtt=week+6+Training
chdl=Recommended+Miles|Actual+Miles
chco=ff0000,00ff00
chxt=x,y
chxr=1,0,15
chxl=0:|Mon|Tue|Wed|Thu|Fri|Sat|Sun|
chd=t:0,3,4,3,0,7,0|0,2,0,3,0,0,7
chbh=10

July 17, 2008 by Programming Running Technology Uncategorized Web 0