19 January, 2010

Default https access for Gmail


Gmail has long offered a more secure connection option over Https, and two years ago let users set it themselves as a default. Now Google is making https the default setting for all Gmail accounts, unless you flip it back.

Given their recent security episode in China, and the ever-expanding realm of devices and portals users can get at Gmail from, it's probably a smart step forward to gently goad users into using a more secure connection standard. Google notes that, although using https creates a slight latency, they believe the trade-off is worth it.

If https presents a problem in your particular IT environment, you can still switch it off in your Settings. Here's Google's explanation:

"If you've previously set your own https preference from Gmail Settings, nothing will change for your account. If you trust the security of your network and don't want default https turned on for performance reasons, you can turn it off at any time by choosing "Don't always use https" from the Settings menu. Gmail will still always encrypt the login page to protect your password. Google Apps users whose admins have not already defaulted their entire domains to https will have the same option."

Google also notes that Offline Gmail users who weren't already using https as a default may see some issues, but they suggest a work-around.

Does a default https present problems for your own Gmail account? Happy to see the security struggle moving a step forward? Tell us your take in the comments.

Your Passwords Aren't As Secure As You Think

If you allow applications to save your passwords, anyone with physical access to your PC can decode them unless you're properly encrypting them—and chances are pretty good you're not. Let's walk through the right and wrong ways to store your passwords.

For the purpose of this article, we'll assume that the people you allow into your house are trustworthy enough not to hack your passwords, and your laptop has been stolen instead—but the tips here should apply to either scenario. Regardless of how you choose to save your passwords, you should make sure to use great passwords and even stronger answers for security questions.

Once You Click "Remember Password" It's All Over
Almost any application that requires you to login to something will also provide an option to save your password, and once you've done that, your password may as well be plain text. Behind the scenes, even if the application encrypts the account information, it's doing so with a static key that can be easily deciphered through some reverse engineering, and somebody not only can, but already has created a utility to recover those passwords.

It doesn't even matter all that much if you've got a tough Windows password; anybody with physical access to your PC can use an Ubuntu Live CD to copy all of your data onto an external drive without modifying anything, and crack your files on another machine whenever they please (assuming you don't have your entire hard drive encrypted). If they had a little more time, they could use Ophcrack to figure out your password, or they could just be mean and use the System Rescue CD to change your Windows password.

Once that person has access to your files, they can recover your passwords with free tools easily—you can recover passwords in a few clicks from Outlook, Instant Messenger, Wi-Fi, Internet Explorer, Firefox, Chrome, or any number of other applications. All it takes is a quick Google search to find even more cracking utilities.

Pidgin Stores Passwords in Plain Text
That's right, your favorite open-source, multi-protocol instant messenger client stores your passwords in plain text. If you don't believe me, just open up your %appdata%\.purple\accounts.xml file in your favorite text editor, and you'll see your passwords right there for anybody to read.

The decision to store the passwords in plain text is a deliberate one that's been thoughtfully considered, and while you might initially think it's a terribly insecure way to handle security, keep in mind that you can simply download any number of utilities like Nirsoft's MessenPass and recover the passwords from AIM, Windows Live Messenger, Trillian, Miranda, Google Talk, Digsby, etc. The Pidgin developers point out that their option is actually the preferred method for security:

Having our passwords in plaintext is more secure than obfuscating them precisely because, when a user is not misled by a false sense of security, he is likely to use the software in a more secure manner.

The best answer, of course, is to not allow your IM client to store your passwords at all—but if you must store them, you should at least use the built-in Windows encryption, if not a full-blown TrueCrypt setup. Either option would be better than the pseudo-protection most other applications provide.

Password Managers Are the Only Secure Storage
The only truly secure way to store your passwords is to use a password manager to securely track your passwords, combined with a a great master password to protect the rest of your saved passwords—if you use an easy password for your password manager, it would be easy to crack with a brute force attack. Don't lure yourself into a false sense of security by just using one—your password manager password should be at least 10 alpha-numeric characters if you really want to be secure.

You've got a number of great password managers to choose from, like reader favorite Keepass, a cross-platform tool which has many plugins that help you master your passwords and make using a password manager easier to deal with. And, of course, let's not forget that Firefox has a full password manager built right into the application.

Use a Firefox Master Password (With More Than 8 Characters)
If you want to use Firefox to save the passwords for all your web accounts, you should make sure to enable a Firefox Master Password by heading into Tools –> Options –> Security and checking the box for Use a master password.

Once you've done this, Firefox will store all of your passwords with nearly unbreakable AES encryption—providing you use a password with more than 8 alpha-numeric characters and at least one capitalized letter. If you used a weak and pathetic password like "secret", it could be broken in a matter of minutes with a brute force cracking tool, but a decent 8+ random character password will take at least 73 years for a brute force attack.

Each time you start Firefox and go to a site that requires a saved password, you'll be first prompted for your master password. By default, the master password authentication will be active for the entire session, but you can use the Master Password Timeout extension to lock your master password again after a certain interval, which is handy if you walk away from your desk without remembering to lock it with Win+L.

Use TrueCrypt to Encrypt Everything
Rather than deal with password managers or whether or not to save your passwords, you could simply create a separate, encrypted TrueCrypt drive, and use portable versions of your applications to keep everything totally secure. If you're even more paranoid, you can use TrueCrypt to encrypt the entire hard drive—you will be prompted for a password every time you boot, but you can relax knowing that anything you do will be encrypted, even if you use scripts with your passwords stored in plain text. If TrueCrypt isn't your thing, you can use the built-in encryption functionality in Windows—just keep in mind that if you change your password your data will be inaccessible, and your Windows password can be cracked, giving them full access to your files.
Are you already using a password manager or encryption to keep your passwords secure? Share your best password security tips in the comments.

01 December, 2009

Access Facebook and Twitter From Gmail

iGoogle gadgets can be added to Gmail. Since that is not what they are originally made for, they can look a little weird or just not be of any use at all. But these two gadgets works!

The Twitter gadget is actually made for Gmail, and the great thing is that it goes "fullscreen", that is, instead of your email you see tweets! The same goes for Facebook, although it's originally made for
iGoogle. But it also goes fullscreen, you just have to click on "Expand" inside the gadget box.

To install them, just do the following:

1. Go to Settings –> Labs, find "Add any gadget by URL" and activate it.
2. Find a XML gadget for Gmail or iGoogle.
3. Go to Settings –> Gadgets, enter the gadget URL into the text box and click Add.

These are the gadget URLs:
Twitter - http://twittergadget.appspot.com/gadget-gmail.xml
Facebook - http://hosting.gmodules.com/ig/gadgets/file/104971404861070329537/facebook.xml

29 January, 2008

Cisco CCNA Questions & Answers

Cisco CCNA All Modules Question And Answers: - - Enjoy

CCNA 1
cisco ccna semester 1 module 1
cisco ccna semester 1 module 2
cisco ccna semester 1 module 3
cisco ccna semester 1 module 4
cisco ccna semester 1 module 5
cisco ccna semester 1 module 6
cisco ccna semester 1 module 7
cisco ccna semester 1 module 8
cisco ccna semester 1 module 9
cisco ccna semester 1 module 10
cisco ccna semester 1 module 11
cisco ccna semester 1 Final EXAM

CCNA 2
cisco ccna semester 2 module 1
cisco ccna semester 2 module 2
cisco ccna semester 2 module 3
cisco ccna semester 2 module 4
cisco ccna semester 2 module 5
cisco ccna semester 2 module 6
cisco ccna semester 2 module 7
cisco ccna semester 2 module 8
cisco ccna semester 2 module 9
cisco ccna semester 2 module 10
cisco ccna semester 2 module 11
cisco ccna semester 2 Final EXAM

CCNA 3
cisco ccna semester 3 module 1
cisco ccna semester 3 module 2
cisco ccna semester 3 module 3
cisco ccna semester 3 module 4
cisco ccna semester 3 module 5
cisco ccna semester 3 module 6
cisco ccna semester 3 module 7
cisco ccna semester 3 module 8
cisco ccna semester 3 module 9
cisco ccna semester 3 Final EXAM

CCNA 4
cisco ccna semester 4 module 1
cisco ccna semester 4 module 2
cisco ccna semester 4 module 3
cisco ccna semester 4 module 4
cisco ccna semester 4 module 5
cisco ccna semester 4 module 6
cisco ccna semester 4 Final EXAM

22 December, 2007

Decision Support System

Definition:

For Little, a DSS is a "model-based set of procedures for processing data and judgments to assist a manager in his decision-making." Moore and Chang define DSS as extendible systems capable of supporting ad hoc data analysis and decision modeling, oriented toward future planning, and used at irregular, unplanned intervals. For Sprague and Carlson, DSS are "interactive computer-based systems that help decision makers utilize data and models to solve unstructured problems."

Decision support systems are a class of computer-based information systems including knowledge based systems that support decision making activities. Decision support systems are man – machine system for decision making purposes. Man part is more open & probabilistic while the machine part is more closed and deterministic. DSS must be closed system with feedback, external to the system. It uses the feedback to adjust output. Feedback is not internal like an elevator. The user provides judgmental inputs to the DSS.

According to the mode of assistance, DSS can be categorized into five different models:

  • A model-driven DSS emphasizes access to and manipulation of a statistical, financial, optimization, or simulation model. Model-driven DSS use data and parameters provided by users to assist decision makers in analyzing a situation; they are not necessarily data intensive.
  • A communication-driven DSS supports more than one person working on a shared task; examples include integrated tools like Microsoft's NetMeeting or Groove.
  • A data-driven DSS or data-oriented DSS emphasizes access to and manipulation of a time series of internal company data and, sometimes, external data.
  • A document-driven DSS manages, retrieves and manipulates unstructured information in a variety of electronic formats.
  • A knowledge-driven DSS provides specialized problem solving expertise stored as facts, rules, procedures, or in similar structures; examples are Expert Systems.

Algorithms Developed For Implementing D.S.S.:

There are many algorithms such as Analytical Hierarchical Process (AHP), Analytical Network Process (ANP), The Simple Multi Attribute Rating Technique (SMART) and other AI and Expert system technique.
ANP is best used in the case when there is interdependence among the items and the alternatives. ANP does not require independence among elements, so it can be used as an effective tool in these cases. Thus, this dependency increases complexity in design and sometimes becomes overhead when there is no dependencies among the parameters. It is the more general form of AHP.AHP is the specific form of ANP used in multi-criteria decision analysis. Both the AHP and the ANP derive ratio scale priorities for elements and clusters of elements by making paired comparisons of elements on a common property or criterion.

Analytical Hierarchical Process:

The Analytic Hierarchy Process (AHP) is a structured technique for dealing with complex decisions. The AHP provides a comprehensive and rational framework for structuring a problem, for representing and quantifying its elements, for relating those elements to overall goals, and for evaluating alternative solutions.
In AHP, first the decision problem is decomposed into a hierarchy of more easily comprehended sub-problems, each of which can be analyzed easily.
Once the hierarchy is built, various elements are systematically evaluated comparing them to one another in pairs. In making the comparisons, judgments about the elements' relative meaning and importance can be provided. It is the essence of the AHP that human judgments, and not just the underlying information, can be used in performing the evaluations.
The AHP converts the judgments to numerical values that can be processed, evaluated and compared over the entire range of the problem. A numerical weight or priority is derived for each element of the hierarchy, allowing diverse and often incommensurable elements to be compared to one another in a rational and consistent way. This capability distinguishes the AHP from other decision making techniques.
Although AHP is used in wide range by lots of decision makers, we still can’t deny the fact that it has a flaw. Researchers have found that the flaws in AHP are significant and lead to various types of decision errors.
Some flaws of AHP are:

  • The Use of Arbitrary Scales (1,3,5,7,9 or their reciprocal (1,1/3,1/5,1/7,1/9))
  • Rank Reversal
  • Inducement of Nonexistent Order

References:

http://en.wikipedia.org/wiki/Decision_support_system
http://en.wikipedia.org/wiki/Analytic_Hierarchy_Process
http://mat.gsia.cmu.edu/mstc/multiple/node4.html