Configuring User Permission on Files and Folders

This post was made by me (22094775) for additional assignment on Operating System class :)

Windows XP, Vista, and 7 makes it possible to a system administrator to configure user permission on specific files and folders. This is important for security and privacy reasons, so here is how to check the current user permission settings in a file/folder:

1. Open the file/folder properties
2. Go to the security tab 
3. There, you can see the list of users and their permissions

You will find several users, some you might know. Some of them are groups of users (will  be marked with [G] on following list). Here are some common names that you'll find there:

• Administrators[G]
• This group contains all human users with administrator privileges
• Users[G]
• This group contains all human users, with or without administrator privileges
• OWNER/CREATOR
• This user is the one that created the file/folder
• SYSTEM
• Not a human user, the name is self-explanatory, it's recommended that you don't mess up with this user's permission settings
• Everyone
• Everyone: Administrators, non-administrators, system, etc. This user's setting is the one you'd like to modify to easily configure access for all users.

You will also find several other users which you or your system administrator created, you might want to make a new temporary user account in case you want to play (or learn) user permission control configuration. Some users have strange names, such as S-1-5-123 or so, they are (usually) printers or file sharing servers, do not modify unless you know what to do with them.

There are several kind of permissions, before we go to configuration part, here are some short explanations of what they are:

• Full Control
• As the name suggests, this permission gives user or group full control to a file/folder including read, write, modify, and execute
• Modify
• This permission allows user/group to change the content of a file/folder, by giving this permission to a user, you'll also give read and write permission
• Read & Execute
• With this, a user/group is allowed to read the file/folder contents and run any executables inside
• List Folder Contents
• Not really important and self-explanatory, the effect of this permission can only be seen when you're playing with dir command on command prompt
• Read
• Same with read and execute, but without privilege to run executables
• Write
• This permission allows user/group to change the content of a file/folder including creating new file inside a folder

To make it easier for you to configure the permissions, here provided several scenarios and presets that you can use:

• Blocking file/folder access to anyone other than you

1. Under group and user names, click Add button
2. Click Advanced button, then click Find Now
3. Find your user name, click OK
4. Now you should find your user name on the list, select it
5. On permission, tick Full Control on Allow
6. Now select Everyone on user name list
7. On permission, tick Full Control on Deny 

• Modifying file/folder access to specific user account

1. If you can find the user name on list, skip to step 5
2. Under group and user names, click Add button
3. Click Advanced button, then click Find Now
4. Find the user name whose permission you wanted to modify, click OK
5. Find the user on list, select
6. Now it depends on how you'd like the permission modified

• To make the file/folder Read Only for the user, tick Read or Read & Execute on Allow and Write on Deny
• To allow user to read and write but not to delete the file/folder, tick Read and Write on Allow, leave the others blank
• To block permission completely, tick Full Control on Deny

Special thanks to Mr. Antonius RC S.Kom, M.Cs

Mozilla Firefox vs Google Chrome

Google Chrome, it only needs a whole year (Dec 2008 - Dec 2009) to be the third most widely used browser in the world (4.4%).


We will compare Google Chrome with Firefox 3.5 (No Add-On).

Memory Usage

Firefox is the lightest browser in the world, I also consider Google Chrome as a very light browser but it consumes about 10-20% more memory than Firefox (depend on the number of tabs opened). But we will see that the larger consumption of memory is not a waste. Let's go to the next comparison.

Display

When you heard about Windows Vista, you'll imagine an Operating System with a wonderful display, and that's what you get on Google Chrome, the name shows what's inside. Firefox is still using a standard display for the user interface, buttons, and theme. Google Chrome will blind your eyes, it has a much better display (on both browser theme and webpage display) than Firefox, and it consumes less memory and CPU usage compared to Opera, another browser that has a magnificent display.

Page Load Time

No doubt, Firefox is the best on page load time, Google Chrome takes several more seconds (or milliseconds) to finish loading a webpage. Personally I won't mind waiting a few seconds more in order to get a better display, but there are users out there that will kick their keyboard and yell at a slower browser.

Conclusion (and facts)

It's all about appearance and performace, everyone has their own preference. For those who love eye candies, Firefox will bore them. For those who prefer speed, Google Chrome will waste their precious browsing time (a few milliseconds perhaps).

 And we will see a comparison from Google Trends

Blue = Firefox and Red = Chrome

We can see that at Chrome's first launching day, lots of people look for it (on Google of course) and that's a very good start for a new software. Then after the 'frenzy' was over, the search volume returned to a reasonable amount, but still that's not a small number for a new software (even the new release of Firefox 3 doesn't make the search volume for 'Firefox' show a significant increase). Slowly but surely, Chrome's search volume goes up over time. It will catch up Firefox's search volume before 2011 unless Google does something stupid and mess everything up.

Dual Core? Quad Core? Nope, 48 Core!

"That's insane!" was my first reaction when I read this article's title. It's still 2009 and a Quad Core processor is more than enough, why would you need a 48 Core?

After I read the article, I changed my opinion. That's a cool project, the processor wasn't made for a usual computer, it's for a super computer capable of doing a lot of thing that human can do. The 48 core processor contains 1.3 billion transistors and nicknamed “single-chip cloud computer”. It executes commands quickly and smoothly.

...powerful enough to do more of what humans can.
...can carry 64 gigabytes of data per second.
...can accommodate a maximum of 64GB of memory.

So they're trying to make a computer that is stronger than human mind. A computer that (probably) is smarter than human. This is the time when computer will takeover the world (well it's close to 2012 after all - just kidding). With this kind of computer, everything will be easier, all difficulties will be solved by the computer.

But, there are some problems:
1. Needs a huge amount of power
2. Easily overheated
3. Hard to synchronize every core

Fortunately Intel anticipated that, the processor will use "adaptive mode", unused parts of the processor will be turned of when idle. And for the synchronization problem, they're still working on it.

Awesome!

Sources:
http://news.cnet.com
http://news.bbc.co.uk
http://www.wired.com

Related articles:
100 Cores 
Thousands of processing cores

Overclock: why & why not?

Overclocking is the process of running a computer component at a higher clock rate (more clock cycles per second) than it was designed for or was specified by the manufacturer, usually practiced by enthusiasts seeking an increase in the performance of their computers. (http://en.wikipedia.org/wiki/Overclocking)

We can say that overclocking will 'force' our computer (especially the CPU and/or graphic card) to work harder in order to make it able to produce more and better result than usual in a period of time. For people who want to increase the performance of their computer without upgrade, overclocking is the best (for several cases) solution.

Why:

• Great solution for low-end computers, you don't have to upgrade the components
• Reducing lag on heavy memory usage
• Faster data processing
• Better game performance and graphics 
• Increase time before an upgrade is needed 
• Can be used to test the component's durability

Why not:

• Overclocking will damage your computer's component, reducing its lifespan
• More electrical power consumption
• Overclocked components produce more heat that may damage another components
• Excessive heat (risk of fire) demands computer to be turned off every several hours
• Void the component's warranty
• Overclocked components have very low reselling prices
  

Sample of overclocking results

Strong password for better protection

To get a better protection for your account (online/offline) you'll need a strong password. Here are some tips in building a strong password:

1. Use words/sentence that are hard for people to guess, but easy for you to remember, make sure it's long enough so that people can't brute-force it
Example: iloveblogging

2. Include uppercase and numbers, make it complex, but make sure you can remember it
Example: 1loveBlogginG

3. If possible, use at least one special character ~!@#$%^&*()<>?
Example: 1(love)BlogginG!

4. Check the password strength using Microsoft's Password Checker

And a strong password isn't enough:

1. Never log in to your account on an unsecure network.
2. If you need to log in to your account using another person's computer, be sure to use one of these software to avoid keyloggers.
3. Don't write down your password, that's too risky. If you find it hard to memorize password, just write a hint so that you can remember it.
4. Using a random password generator isn't recommended, it has several patterns that can be easily brute-forced

 Beware! Brute-force attackers are everywhere!