Fedora is a linux distribution sponsored by Red Hat and supported volunteers. The latest release is Fedora 9 (code named Sulphur) and was released on 13 May 2008. Fedora 9 contains a lot of feature improvements and is now more user friendly than ever!  Fedora features the latest Linux kernel (2.6.25) and hence can run on latest hardware.

So what is new in Fedora 9 (Sulphur) ?

1. GNOME 2.22 - New version of GNOME brings a number of features which includes performance improvements. UI improvements include an enhanced world clock with multiple time zone displays. This version also includes an updated display manager with features such as power management on login screen.

2. Linux Kernel 2.6.25 - Latest Kernel support means a number of core enhancements such as improved virtualization support, CPU "group scheduling", USB authorization and new wireless configuration interface.

3. Persistent Live USB Support - Live USB support is not something new. Knoppix was one of the early distributions which could run from a Live CD. As USB capacity increased, live distributions started appearing on it. But what makes Fedora 9 unique is that now Live USB can store user preferences! This means that Live USB can be used a sort of portable Fedora 9 machine! Wherever you go, you can plugin in the USB, work on the Fedora 9 and then save data on it!

4. Seamless Upgrade - Fedora 9 features automated and seamless upgrade similar to Windows update. The latest preupgrade software can even be used to upgrade from Fedora 7 to Fedora 8!

5. Latest Software (Firefox 3 beta 5, Pidgin, Gimp etc.) - Fedora 9 Sulphur features all the latest software including Firefox 3. It also includes Pidgin, gEDIT, GIMP, Perl 5.10.0 etc.

Other new stuff in Fedora 9 include ext4 support, improved virtual machine support, bluetooth enhancements, PackageIt front-end to yum, Font improvements and built in support for encrypted file system.

Fedora  9 screenshot,

Further Resources

• Download Fedora 9 Sulphur
• Summary of Fedora 9 features

From April 24, 2008 AVG is releasing a free version of the popular AVG Anti-Virus. This version (8.0) contains both anti virus and anti spyware and is the best free option available in the market. Unfortunately the free version lacks proactive scanning of browsing links to block malicious URLs (which contain spam/keyloggers).

AVG free offers fast scanning since spyware/antivirus engines are integrated. Another good thing is that it has a low load on the system.  It also comes with safe search - each time you search online, Safe Search checks the results on the fly to give you an immediate idea of which websites are safe to visit.

The limitations of the free version are,

• No real time link scanning.
• This cannot be installed on Windows server versions.
• No technical support

AVG anti-virus free 8.0 can be downloaded from here.

Captchas are images used by online service providers to prevent automated sign ups. Ideally characters in these images can only be identified by a human. Spammers have been working hard to created a program which can identify captcha characters. They can then randomly create email accounts and then use it for bulk spamming! Since the mail is a genuine email from a well known email provider(Gmail, Hotmail) anti-spam providers cannot block them.

Websense is reporting that spammers have finally managed to write captcha decoding programs for Hotmail which takes only few seconds to decode the characters! The success rate is over 10% and is good enough for spammers.  Here is how spammers make money from this,

1. Spammer releases the automatic signup bot as a virus.

2. An unprotected machine on the Internet gets infected by this bot virus.

3. Bot creates multiple hotmail accounts from victim’s machine using captcha decoding logic.

4. Bot sends advertising messages to multiple mail addresses using the newly created hotmail account.

5. When millions for spam messages are sent, fairly good percentage of them brings business and spammer makes money through affiliate cut.

Whoever wrote this must be pretty good since the Hotmail captcha is pretty difficult interpret even for a human. For example, consider the captach (displayed on the right side) I got when I tried to signup to Hotmail!

Weak captchas have caused havoc earlier. For example, PhpBB forum software captcha was so weak that was hacked in a few days. So if you have a popular forum which is running on PhpBB 2.0, you will soon find majority of new users are from automated signups! It was complicated by the fact that a signed up account can have a live link in the profile.

I think one way to handle the bots will be to have very big set of different captcha styles which will reduce the success rate to below 0.01%. Another way will be to introduce new type of captcha every day so that any decoding program will become obsolete in a day!

Rapidshare is a popular free/premium file sharing service. There are a lot of files available on Rapidshare and not all of them are legal. But what many don’t know is that there are two different sites which run with the Rapidshare logo. The original one is rapidshare.de and the new recently started site is rapidshare.com. Same people are behind both these sites.

But unfortunately if you take an account on rapidshare.com, it WON’T WORK on rapidshare.de and vice versa! Even the account pricing is different between these two sites. For example, rapidshare.de charges 9.90 euro for one month’s service while rapidshare.com charges 6.99 euro for one month.

So before you signup to rapidshare, decide which one you need. If you are looking for a lot of old files, rapidshare.de account is the one you need. But rapidshare.com is where all the new files are added!

Rapidshare claims that they have 220gigabit/s bandwidth and can host upto 5 petabytes of data!

Due to obvious reasons(rapidshare doesn’t support file meta data to avoid copyright issues), rapidshare doesn’t provide any search facility. But there are a couple of third party sites which allows rapidshare search. These sites store the meta data related to rapidshare uploaded files separately. Following are some of the tools you can use to search rapidshare file database.

Rapidshare search engine - This is a web crawler which collects rapidshare links. Not perfect, but useful enough for most searches. Supports ajax search.

RapidLibrary - This is much more precise than rapidshare search engine. Files are indexed from user submissions and also from web crawling.

Microsoft has released beta 1 for Internet Explorer 8. This release is not intended for public release, but is for web developers and designers who want to check out the new features. This can also be used to plan migration of your site to support IE8.

Windows Internet Explorer 8 Beta 1 for Developers is available now in two versions: a stand-alone version for Windows® XP Service Pack 2, Windows XP Professional x64 Edition, and Windows Server® 2003; and an enhanced version built to take advantage of the Windows Vista® platform. Support for Windows Vista Service Pack 1 is also planned once it reaches final release in early 2008.

Internet Explorer 8 gives more importance to standards compliance and interoperability. Now backward compatibility is taking a back seat. This means that if your site is not standards compliant, it may not render correctly in IE8!! It is possible to switch IE8 to IE7 mode, but it is not on by default.

IE8 aims for full compliance to CSS 2.1 standards and will be working towards HTML 5 standard. IE8 currently passes Acid2 test in default mode.

Major new features in IE8

Activities - These are a set of contextual services provided by browser on any Webpage. Using the context menu, user can send or receive information from external websites.  For example, if you want to add a page to Digg, you can just right click and select "Add to Digg" option. Cool, eh?

Webslices - Portions of a webpage can be marked as Web slices. It is possible for the browser user to subscribe to content inside a slice. Once subscribed it will appear on favorites bar. Whenever content in that slice change, you can preview it without leaving the current page you are viewing! Many popular sites such as Facebook and Ebay has already started using Webslices!

Domain highlighting in address bar - IE8 will highlight the owning domain of the web page you are viewing. This in future should bring down the incidents of phishing by fake sites.

You can download IE 8 beta 1 from here.

Grails is an open source Web application framework written for Java platform. It is based on the Groovy programming language and is a competitor to Ruby on Rails.

Grails boost programmer productivity by eliminating configuration effort using the "coding by convention" paradigm.

Grails eliminates the need for downloading and configuring multiple sets of applications for starting development of a Java Web application. Grails provides a single package which contains test application server, ORM tool (Hibernate) etc. So in a nutshell, Grails is J2EE on steroids.

Books on Groovy

In order to be an expert on Grails, you need to learn Groovy. Groovy is a scripting language based on Java. Following are some of the good books available in Groovy.

Groovy in Action - This takes a detailed look at the Java scripting language Groovy. This is the favorite book on Groovy.

Groovy Recipes: Greasing the Wheels of Java- Groovy recipes one programming problem at a time and explores how it can be done in Groovy. This is a must have book if you want to be quickly productive in Groovy. This book also looks at Grails.

Programming Groovy: Dynamic Productivity for the Java Developer - This book is not yet released. This is intended for new programmers and will contain both Groovy fundamentals and advanced Groovy topics such as meta programming, unit testing and domain specific language creation.

Books on Grails

The Definitive Guide to Grails (Definitive Guide) - This is a comprehensive reference to Grails. It takes you through the complete Grails development lifecycle such as project configuration and automatic ORM mapping. This also contains a quick introduction to Groovy.

Getting Started with Grails - This book is available as a free Grails book download (PDF). This is a quick introduction to Grails platform. It takes you through the framework step by step. It also explores how a Web application is turned into concrete code from abstract code.

I recently came across a high speed domain search called 10xwhois. This service shows the domain availability as soon as you type in the domain name. You can also save a list of favorite domain extensions and can also bookmark favorite domain searches.

From the author’s site,

10xwhois has support for keyboard shortcuts and you can also save your domain searches in a favorite list. This tool is a Java web application and is hosted on a dedicated server. It is designed to handle high volume requests and is probably the fastest domain search service on internet.

I am still working on a couple of enhancements such as domain suggest and 10xwhois widgets…

This tool also is a demonstration of the effectiveness of Ajax Web paradigm.

Globat hosting suffered a major downtime on February 21st 2008. The primary network switch and backup switch completely failed and took down the entire network including globat website. This site was also down for about 12 hours! From the mail I have received,

Our primary network switch in our main datacenter in downtown Los Angeles failed completely and despite tremendous efforts by our technical emergency response team could not be brought back online. This switch is a major brand name piece of equipment and as such it contains internal redundancy. We were able to switch over to the back up circuitry and begin bringing the system back online at which time, for yet unknown reasons, the entire devise, including backup system, failed completely.

After a short deliberation we decided to rush a new switch from our vendor’s nearest warehouse to our data center. While waiting for the replacement we initiated a work around to at least get email service re-established. After several attempts all email systems finally went live and back to normal at approximately 10:00am Pacific Time.

When the new switch arrived we went through the installation and testing process and as a result were able to bring all our services back online, but not before we had suffered a 5-hour outage for e-mail services and an 8-hour outage for Web related services. In Globat’s entire 6 year history, we have never experienced anything even remotely like this! The outage was so severe
that it affected our own Web sites and all but one of our telephone lines so we were unable to communicate with our customers to update anybody about the status of the incident. We decided to ask some of our staff members to post updates on well known Internet forums, which helped a little in disseminating the information.

I had recently installed Windows Live Messenger on my pc at work. Along with it came a pesky toolbar addon called Windows Live Search. This gets attached after the URL box and is irritating to say the least. I prefer to use Google and I don’t need a toolbar!

I thought it should be pretty easy to remove Windows Live Search. It turned out that there is no direct option to remove Live Search! What you can do is to change the search provider. But hey! I don’t want a freaking toolbar!

After a bit of google research, I came to know that there is a registry hack to prevent the Windows live search textbar. Open up the regedit and look for the key HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Internet Explorer\InfoDelivery\Restrictions. Sometimes you may see path only up to Microsoft. In that case add the path Internet Explorer\InfoDelivery\Restrictions. Then add a DWORD under Restrictions named NoSearchBox and set its value to 1.

A new virus called Trojan.Mebroot has been infecting windows computers recently. What makes this virus unique is that it uses Master Boot Record (MBR) to hide itself. MBR contains operating system loading code which is executed first.

A machine gets infected when the user of the system accesses Websites intended to spread the virus (such as warez or illegal downloads). Mebroot uses Internet Explorer vulnerability to write directly to the Master Boot Record of the machine! The trojan itself is around 450kb in size and is stored in the last sectors of the harddisk. It then creates a backdoor on the machine.

Once the backdoor has been established, the program looks for any user access to internet banking sites. It then sends the captured banking userid/password etc. to a thirdparty site! Pretty impressive, eh?

It is estimated that over 5000 machines are affected by this virus.

The easiest way to remove this virus is to run “fixmbr” command from Windows recovery console. This overwrites the virus entry on MBR. Also some of the latest BIOS setting allows you to make MBR readonly. Any modification to MBR will throw a BIOS warning! So enable MBR protection today.

Lastly never visit any Website which offers warez, cracks, serials or free downloads. The real purpose of most of these sites are to spread keyloggers and other types of viruses. If you really want to check those sites, create a virtual pc using vmware or windows virtual pc exclusively for that purpose.

HECToR is a new supercomputer assembled at University of Edinburgh, UK. This is one of the fastest machines in Europe which can do 60 million million calculations per second! The total cost of this machine is over $200 million and equivalent to over 10,000 desktop computers.

HECToR contains over 5000 AMD 2.8GHZ dual core Opteron processors the peak performance is 63Tflops. The total memory of HECToR is 33TB (6GB per processor)!! The storage used is high performance RAID disks with a total capacity of 576TB. HECToR uses Unicos/lc as the operating system and has two components - compute node linux for compute nodes and linux distro(SUSE Linux) for service nodes. The communication network uses 6 sets of Seastar2 chip based system and each link offers bi-directional bandwidth of 7.6GB/sec!

HECToR (High-End Computing Terascale Resource) is a project funded by research councils in UK and this facility is available to researchers in UK Universities. The main use of this supercomputer will be in simulation of complex natural phenomena such as climate change prediction.

HECToR is composed of 66 individual units as shown below and each of the unit is as big as a large shelf!

You can see the current status of HECToR supercomputer here!

Ruby on Rails is the hot new Web application framework based on Ruby language. It offers unmatched programmer productivity and has taken over the Web2.0 application development. In this post, I will look at some of the free tutorials and free ebooks on Ruby on Rails available for download.

1. Tutorial on Ruby on Rails - This is a beginner’s tutorial on RoR. Hosted by RoR official wiki, this is the best place to start on Ruby on Rails.

2. Rolling with Ruby on Rails Part I and Part II - This tutorial written by Curt Hibbs is a good introduction to Ruby on Rails. It takes you through a sample application end to end.

3. Learn Ruby on Rails in 4 days! - This is a PDF book on Ruby on Rails. It gives you a toolbox of Rails techniques and can be used as a bridge from Rails basics to Advanced rails.

4. Fast track Web application development with Ruby on Rails - This article from IBM takes a quick look at developing a Rails Web application.

5. Beginner’s guide to Ruby on Rails - Another introductory tutorial on Ruby on Rails.

Now you can have your own personal language translator! All you have to do is to add him as a friend in Google talk!

Google has released 24 language translator bot in Google Talk. These are named in using language codes - for example a contact named en2fr will translate from English to French. You just need to add en2fr as a friend and then anything you type to en2fr will be translated to french instantly!

Since this service uses XMPP open protocol, you can write different applications to make use of the underlying engine. For example, you can enable this chat translation facility on your own site using the Google talk engine.

Machine translation comes with its own risks, so don’t try it on your date

Want to host your own Instant Messenger? Then you should try out Ajax im. This is very compact custom instant messenger which is based on PHP and AJAX. The complete download is less than 300kb! In order to host this on your server, you need a MySQL database and PHP support.

Since this is AJAX based, you can integrate this within your existing site. You can also host this as part of your intranet. It is not as sophisticated as any of the commercial ones, but still is good enough as supporting tool to your site.  You can try out a sample implementation here.

Recently Orkut is focusing more on the privacy options available for its users. They have announced a new feature while allows you to keep Orkut privacy options. This means that now you can ensure that your scraps, videos, feeds and photos are only visible to your friends!

To enable privacy option, go to your profile and click on "settings" link. Then click on "privacy" tab on the right top. Then restrict the access of your videos, scraps etc. to "friends" only.

But why do you need to take this precaution? The reason is this - Internet has shortage of stalkers and criminals. So it is very important that your personal information is kept private. Also ensure that you add only those people whom you know personally as friends. Otherwise turning on privacy will be of no use!

Many people tend to post private information such as email or phone numbers in the scrap. Some even go to the extend of publishing their address in scraps. So it is better to keep the scrapbook  private.