Power Buzzer

How often on average do you have to call members of your family each day to tell them that dinner is ready, it’s time to leave, and the like? The person you want is usually in a different room, such as the hobby room or bedroom. A powerful buzzer in the room, combined with a pushbutton at the bottom of the stairs or in the kitchen, could be very handy in such situations. The heart of this circuit is formed by IC1, a TDA2030. This IC has built-in thermal protection, so it’s not likely to quickly give up the ghost. R1 and R2 apply a voltage equal to half the supply voltage to the plus input of the opamp. R3 provides positive feedback. Finally, the combination of C2, R4 and trimmer P12 determines the oscillation frequency of the circuit.Power Buzzer Circuit Diagram ...

How Make Simple Battery Isolator

This circuit is even simpler and employs a 6V feed from one of the stator connections on the vehicle’s alternator. This is connected to a 6V automotive relay (RLY1) which controls a Continuous Duty Solenoid (RLY2). This solenoid electrically connects or isolates the batteries. When the engine is started and the alternator stator voltage rises, the 6V relay turns on. This turns on the Continuous Duty Solenoid to connect the two batteries in parallel. As long as the engine is running, the vehicle’s alternator will maintain charge in both batteries.
When the engine is shut down, the alternator stator voltage drops and the Continuous Duty Solenoid switches off, thus isolating the second battery from the vehicle’s electrical system. Provided that camping accessories are only connected to the second battery, the main battery should never discharge. Because the concept is entirely dependent upon the alternator’s stator output voltage, you cannot forget to turn the system on or off as it happens automatically.

Overclocking

What is Overclocking?
Overclocking is the process of making various components of your computer run at faster speeds than they do when you first buy them. For instance, if you buy a Pentium 4 3.2GHz processor, and you want it to run faster, you could overclock the processor to make it run at 3.6GHz.

¡Disclaimer!
WARNING: Overclocking can F up your stuff. Overclocking wares down the hardware and the life-expectancy of the entire computer will be lowered if you overclock. If you attempt to overclock, I, Rogue_Jedi, and Overclockers.com and its inhabitants are not responsible for anything broken or damaged when using this guide.
This guide is merely for those who accept the possible outcomes of this overclocking guide/FAQ, and overclocking in general.

Why would you want to overclock? Well, the most obvious reason is that you can get more out of a processor than what you payed for. You can buy a relatively cheap processor and overclock it to run at the speed of a much more expensive processor. If you're willing to put in the time and effort, overclocking can save you a bunch of money in the future or, if you need to be at the bleeding edge like me, can give you a faster processor than you could possibly buy from a store

The Dangers of Overclocking
First of all, let me say that if you are careful and know what you are doing, it will be very hard for you to do any permanent damage to your computer by overclocking. Your computer will either crash or just refuse to boot if you are pushing the system too far. It's very hard to fry your system by just pushing it to it's limits.

There are dangers, however. The first and most common danger is heat. When you make a component of your computer do more work than it used to, it's going to generate more heat. If you don't have sufficient cooling, your system can and will overheat. By itself, overheating cannot kill your computer, though. The only way that you will kill your computer by overheating is if you repeatedly try to run the system at temperatures higher than recommended. As I said, you should try to stay under 60 C.

Don't get overly worried about overheating issues, though. You will see signs before your system gets fried. Random crashes are the most common sign. Overheating is also easily prevented with the use of thermal sensors which can tell you how hot your system is running. If you see a temperature that you think is too high, either run the system at a lower speed or get some better cooling. I will go over cooling later in this guide.

The other "danger" of overclocking is that it can reduce the lifespan of your components. When you run more voltage through a component, it's lifespan decreases. A small boost won't have much of an affect, but if you plan on using a large overclock, you will want to be aware of the decrease in lifespan. This is not usually an issue, however, since anybody that is overclocking likely will not be using the same components for more than 4-5 years, and it is unlikely that any of your components will fail before 4-5 years regardless of how much voltage you run through it. Most processors are designed to last for up to 10 years, so losing a few of those years is usually worth the increase in performance in the mind of an overclocker.

The Basics
To understand how to overclock your system, you must first understand how your system works. The most common component to overclock is your processor.

When you buy a processor, or CPU, you will see it's operating speed. For instance, a Pentium 4 3.2GHz CPU runs at 3.2GHz, or 3200 MHz. This is a measurement of how many clock cycles the processor goes through in one second. A clock cycle is a period of time in which a processor can carry out a given amount of instructions. So, logically, the more clock cycles a processor can execute in one second, the faster it can process information and the faster your system will run. One MHz is one million clock cycles per second, so a 3.2GHz processor can go through 3,200,000,000, or 3 billion two hundred million clock cycles in every second. Pretty amazing, right?

The goal of overclocking is to raise the GHz rating of your processor so that it can go through more clock cycles every second. The formula for the speed of your processor if this:

FSB (in MHz) x Multiplier=Speed in MHz.

Now to explain what the FSB and Multiplier are:

The FSB (or, for AMD processors, the HTT*), or Front Side Bus, is the channel through which your entire system communicates with your CPU. So, obviously, the faster your FSB can run, the faster your entire system can run.

CPU manufacturers have found ways to increase the effective speed of the FSB of a CPU. They simply send more instructions in every clock cycle. So instead of sending one instruction every one clock cycle, CPU manufacturers have found ways to send two instructions per clock cycle (AMD CPUs) or even four instructions per clock cycle (Intel CPUs). So, when you look at a CPU and see it's FSB speed, you must realize that it is not really running at that speed. Intel CPUs are "quad pumped", meaning they send 4 instructions per clock cycle. This means that if you see an FSB of 800MHz, the underlying FSB speed is really only 200MHz, but it is sending 4 instructions per clock cycle so it achieves an effective speed of 800MHz. The same logic can be applied to AMD CPUs, but they are only "double pumped", meaning they only send 2 instructions per clock cycle. So an FSB of 400MHz on an AMD CPU is comprised of an underlying 200MHz FSB sending 2 instructions per clock cycle.

This is important because when you are overclocking, you will be dealing with the real FSB speed of the CPU, not the effective CPU speed.

The multiplier portion of the speed equation is nothing more than a number that, when multiplied by the FSB speed, will give you the total speed of the processor. For instance, if you have a CPU that has a 200MHz FSB (real FSB speed, before it is double or quad pumped) and has a multiplier of 10, then the equation becomes:

(FSB) 200MHz x (Multiplier) 10= 2000MHz CPU speed, or 2.0GHz.

On some CPUs, such as the Intel processors since 1998, the multiplier is locked and cannot be changed. On others, such as the AMD Athlon 64 processors, the multiplier is "top locked", which means that you can change the multiplier to a lower number but cannot raise it higher than it was originally. On other CPUs, the multiplier is completely unlocked, meaning you can change it to any number that you wish. This type of CPU is an overclockers dream, since you can overclock the CPU simply by raising the multiplier, but is very uncommon nowadays.

It is much easier to raise or lower the multiplier on a CPU than the FSB. This is because, unlike the FSB, the multiplier only effects the CPU speed. When you change the FSB, you are really changing the speed at which every single component of your computer communicates with your CPU. This, in effect, is overclocking all of the other components of your system. This can bring about all sorts of problems when other components that you don't intend to overclock are pushed too far and fail to work. Once you understand how overclocking works, though, you will know how to prevent these issues.

*On AMD Athlon 64 CPUs, the term FSB is really a misnomer. There is no FSB, per se. The FSB is integrated into the chip. This allows the FSB to communicate with the CPU much faster than Intel's standard FSB method. It also can cause some confusion, since the FSB on an Athlon 64 can sometimes be referred to as the HTT. If you see somebody talking about raising the HTT on an Athlon 64 CPU and is talking about speeds that you recognize as common FSB speeds, then just think of the HTT as the FSB. For the most part, they function in the same way and can be treated the same and thinking of the HTT as the FSB can eliminate some possible confusion.


How to Overclock
So now you understand how a processor gets it's speed rating. Great, but how do you raise that speed?

Well, the most common method of overclocking is through the BIOS. The BIOS can be reached by pressing a variety of keys while your system is booting up. The most common key to get into the BIOS is the Delete key, but others may be used such as F1, F2, any other F button, Enter, and some others. Before your system starts loading Windows (or whatever OS you have), it should have a screen that will tell you what button to use at the bottom.

Once you are in the BIOS, assuming that you have a BIOS that supports overclocking*, you should have access to all of the settings needed to overclock your system. The settings that you will most likely be adjusting are:

Multiplier, FSB, RAM Timings, RAM Speed, and RAM Ratio.

On a very basic level, all you are trying to do is to get the highest FSB x Multiplier formula that you can achieve. The easiest way to do this is to just raise the multiplier, but that will not work on most processors since the multiplier is locked. The next method is to simply raise the FSB. This is pretty self explanatory, and all of the RAM issues that have to be dealt with when raising the FSB will be explained below. Once you've found the speed at which the CPU won't go any faster, you have one more option.

If you really want to push your system to the limit, you can try lowering the multiplier in order to raise the FSB even higher. In order to understand this, imagine that you have a 2.0GHz processor that has a 200MHz FSB and a 10x multiplier. So 200MHz x 10=2.0GHz. Obviously, that equation works, but there are other ways to get to 2.0GHz. You could raise the multiplier to 20 and lower the FSB to 100MHz, or you could raise the FSB to 250MHz and lower the multiplier to 8. Both of those combinations would give you the same 2.0GHz that you started out with. So both of those combinations should give you the same system performance, right?

Wrong. Since the FSB is the channel through which your system communicates with your processor, you want it to be as high as possible. So if you lowered the FSB to 100MHz and raised the multiplier to 20, you would still have a clock speed of 2.0GHz, but the rest of the system would be communicating with your processor much slower than before resulting in a loss in system performance.

Ideally, you would want to lower the multiplier in order to raise the FSB as high as possible. In principle, this sounds easy, but it gets complicated when you involve the rest of the system, since the rest of the system is dependent on the FSB as well, chiefly the RAM. Which leads me to the next section on RAM.

*Most retail computer manufacturers use motherboards and BIOSes that do not support overclocking. You won't be able to access the settings you need from the BIOS. There are utilities that will allow you to overclock from your desktop, such as this one, but I don't recommend them since I have never tried them out myself.


RAM and what it has to do with Overclocking
First and foremost, I consider this site to be the Holy Grail of RAM information. Learn to love it

As I said before, the FSB is the pathway through which your system communicates with your CPU. So raising the FSB, in effect, overclocks the rest of your system as well.

The component that is most affected by raising the FSB is your RAM. When you buy RAM, it is rated at a certain speed. I'll use the table from my post to show these speeds:
Quote:
PC-2100 - DDR266
PC-2700 - DDR333
PC-3200 - DDR400
PC-3500 - DDR434
PC-3700 - DDR464
PC-4000 - DDR500
PC-4200 - DDR525
PC-4400 - DDR550
PC-4800 - DDR600

To understand what this table means, lookhere. Note how the RAM's rated speed is DDR PC-4000. Then refer to this table and see how PC-4000 is equivalent to DDR 500.

To understand this, you must first understand how RAM works. RAM, or Random Access Memory, serves as temporary storage of files that the CPU needs to access quickly. For instance, when you load a level in a game, your CPU will load the level into RAM so that it can access the information quickly whenever it needs to, instead of loading the information from the relatively slow hard drive.

The important thing to know is that RAM functions at a certain speed, which is much lower than the CPU speed. Most RAM today runs at speeds between 133MHz and 300MHz. This may confuse you, since those speeds are not listed on my chart.

This is because RAM manufacturers, much like the CPU manufacturers from before, have managed to get RAM to send information twice every RAM clock cycle.* This is the reason for the "DDR" in the RAM speed rating. It stands for Double Data Rate. So DDR 400 means that the RAM operates at an effective speed of 400MHz, with the "400" in DDR 400 standing for the clock speed. Since it is sending instructions twice per clock cycle, that means it's real operating frequency is 200MHz. This works much like AMD's "double pumping" of the FSB.

So go back to the RAM that I linked before. It is listed at a speed of DDR PC-4000. PC-4000 is equivalent to DDR 500, which means that PC-4000 RAM has an effective speed of 500MHz with an underlying 250MHz clock speed.

So what does this all have to do with overclocking?

Well, as I said before, when you raise the FSB, you effectively overclock everything else in your system. This applies to RAM too. RAM that is rated at PC-3200 (DDR 400) is rated to run at speeds up to 200MHz. For a non-overclocker, this is fine, since your FSB won't be over 200MHz anyway.

Problems can occur, though, when you want to raise your FSB to speeds over 200MHz. Since the RAM is only rated to run at speeds up to 200MHz, raising your FSB higher than 200MHz can cause your system to crash. How do you solve this? There are three solutions: using a FSB:RAM ratio, overclocking your RAM, or simply buying RAM rated at a higher speed.

Since you probably only understood the last of those three options, I'll explain them:

FSB:RAM Ratio: If you want to raise your FSB to a higher speed than your RAM supports, you have the option of running your RAM at a lower speed than your FSB. This is done using an FSB:RAM ratio. Basically, the FSB:RAM ratio allows you to select numbers that set up a ratio between your FSB and RAM speeds. So, say you are using the PC-3200 (DDR 400) RAM that I mentioned before which runs at 200MHz. But you want to raise your FSB to 250MHz to overclock your CPU. Obviously, your RAM will not appreciate the raised FSB speed and will most likely cause your system to crash. To solve this, you can set up a 5:4 FSB:RAM ratio. Basically, this ratio will mean that for every 5MHz that your FSB runs at, your RAM will only run at 4MHz.

To make it easier, convert the 5:4 ratio to a 100:80 ratio. So for every 100MHz your FSB runs at, your RAM will only run at 80MHz. Basically, this means that your RAM will only run at 80% of your FSB speed. So with your 250MHz target FSB, running in a 5:4 FSB:RAM ratio, your RAM will be running at 200MHz, which is 80% of 250MHz. This is perfect, since your RAM is rated for 200MHz.

This solution, however, isn't ideal. Running the FSB and RAM with a ratio causes gaps in between the time that the FSB can communicate with the RAM. This causes slowdowns that wouldn't be there if the RAM and the FSB were running at the same speed. If you want the most speed out of your system, using an FSB:RAM ratio wouldn't be the best solution.

Overclocking your RAM
Overclocking your RAM is really very simple. The principle behind overclocking RAM is the same as overclocking your CPU: to get the RAM to run at a higher speed than it is supposed to run at. Luckily, the similarities between the two types of overclocking end there, or else RAM overclocking would be much more complicated than it is

To overclock RAM, you just enter the BIOS and attempt to run the RAM at a higher speed than it is rated at. For instance, you could try to run PC-3200 (DDR 400) RAM at a speed of 210MHz, which would be 10MHz over the rated speed. This could work, but in some cases it will cause the system to crash. If this happens, don't panic. The problem can be solved pretty easily by raising the voltage to your RAM. The voltage to your RAM, also known as vdimm, can be adjusted in most BIOSes. Raise it using the smallest increments available and test each setting to see if it works. Once you find a setting that works, you can either keep it or try to push your RAM farther. If you give the RAM too much voltage, however, it could get fried. For info on what voltages are safe, refer back to my Holy Grail of RAM

The only other thing that you have to worry about when overclocking RAM are the latency timings. These timings are the delays between certain RAM functions. If you want more info on this, you know where to look Basically, if you want to raise the speed of your RAM, you may have to raise the timings. It's not all that complicated, though, and shouldn't be too hard to understand.

That's really all there is to it. If only overclocking the CPU were that easy

Buying RAM rated at a Higher Speed
This one's the simplest thing in this entire guide If you want to raise your FSB to, say, 250MHz, just buy RAM that is rated to run at 250MHz, which would be DDR 500. The only downside to this option is that faster RAM will cost you more than slower RAM. Since overclocking your RAM is relatively simple, you might want to consider buying slower RAM and overclocking it to fit your needs. It could save you over a hundred bucks, depending on what type of RAM you need.


That's basically all you need to know about RAM and overclocking. Now onto the rest of the guide.


Voltage and how it affects Overclocking
There will be a point when you are overclocking and you simply cannot increase the speed of your CPU anymore no matter what you do and how much cooling you have. This is most likely because your CPU is not getting enough voltage. This is very similar to the RAM voltage scenario that I addressed above. To solve this, you simply up the voltage to your CPU, also known as the vcore. Do this in the same fashion described in the RAM section. Once you have enough voltage for the CPU to be stable, you can either keep the CPU at that speed or attempt to overclock it even further. As with the RAM, be careful not to overload the CPU with voltage. Each processor has recommended voltages setup by the manufacturer. Look on the website to find these. Try not to go past the recommended voltages.

Keep in mind that upping the voltage to your CPU will cause much greater heat output. This is why it is essential to have good cooling when overclocking. Which leads me to my next topic...


Cooling
As I said before, when you up the voltage to your CPU, the heat output great increases. This makes proper cooling a necessity. Here is a good set of links related to cooling and a few other topics.

There are basically three "levels" of case cooling:

Air Cooling (Fans)

Water Cooling (look here)

Peltier/Phase Change Cooling (VERY expensive and high end cooling[/b]

I really don't have much knowledge on the Peltier/Phase Change method of cooling, so I won't address it. All you need to know is that it could cost you upwards of $1000 dollars and can keep your CPU at sub-zero temperatures. It's intended for VERY high end overclockers, and I assume that nobody here will be using it.

The other two, however, are much more affordable and realistic.

Everybody knows about air cooling. If you're on a computer now (and I don't know how you'd be seeing this if you're not ), you probably hear a constant humming coming from it. If you look in the back, you will see a fan. This fan is basically all that air cooling is: the use of fans to suck cold air in and push hot air out. There are various ways to set up your fans, but you generally want to have an equal amount of air being sucked in and pushed out. For more info, refer to the link that I gave at the beginning of this section.

Water cooling is more expensive and exotic than air cooling. It is basically the use of pumps and radiators to cool your system more effectively than air cooling. For more info on it, check out the link that I gave next to water cooling before.

Those are the two most commonly used methods of case cooling. Good case cooling, however, is not the only component necessary for a cool computer. The other main component is the CPU Heatsink/Fan, or HSF. The purpose of the HSF is to channel heat away from the CPU and into the case so that it can be pushed out from the case fans. It is necessary to have an HSF on your CPU at all times. Your CPU will be fried in a matter of seconds if it is not.

There are tons of HSF's out there. For a ton of info on HSF's and everything that goes with them, check out this page again. It basically covers all you need to know about HSF's and air cooling.

Try...Super Fast Shutdown

Have you ever wished there was a faster way to shutdown your Windows 2000 , Windows XP ,Windows VISTA and windows 7 computer system?. I mean instantly shut it down! Now you can! Just install Super Fast Shutdown and click on one of the desktop icons created to reboot or shutdown instantly

Try it..!!! Click below...
Download Super fast shutdown

New Extreme Keyboard

New Gaming Keyboard from Logitech.
This new gaming keyboard features a built-in tiltable, game panel color LCD screen with 320 x 240, which is designed to display game statistics, information systems, information on VoIP and even play back videos.The Logitech G19 keyboard features 12 programmable G-keys, with to 3 macros per key, which means you can program up to 36 macros, it also features a built in MR (macro record) key that lets you record a macro directly

System Requirements
Windows ® XP or Windows Vista ®
Mac OS ® X 10.4 and later
Hi-Speed USB 2.0 port
20 MB of available hard disk space
CD-ROM drive
GamePanel ™ LCD requires software supports Logitech ® That GamePanel ™ technology.

New High Quality Printers

1.Epson Artisan 810 All-in-One

Many users are surprised that the prints from this high definition printer can surpass those from photo labs in quality and clarity. A 7.8” touch panel includes an LCD display that allows you to easily view and edit your photos onboard the printer. A unique system lights up only the buttons you need depending on the mode you are in, making the job of processing your photos an easy and intuitive one. Connecting your Artisan 810 to your network is an easy job using its wired Ethernet port or built-in Wi-Fi adapter. The Artisan 810 scans in high definition and comes with OCR software. Other features such as a document feeder and direct printing from iPhone make this printer a great choice.

2.Canon Pixma MG8120 

The Canon Pixma MG8120 offers you an amazing movie print feature that works with high definition movies taken with compatible Canon cameras to print single frames from your favorite memories. For ease of use, the Canon Intelligent Touch system uses a unique lighted button system to help you select only buttons that are relevant to your work at any particular time. Other features such as Wi-Fi connectivity, standalone editing and Canon’s proprietary Photo Fix II technology make this a very attractive printer that will get you professional quality prints that will last for years. This amazing printer has auto-duplex feature to print on both sides of your paper plus a built-in film adapter unit for digitizing slides and film negatives.

Apple iOS Vs Google ANDROID

Apple iOS is an operating system based on Mac OS X. The iOS was developed specially for the iPhone, but this was later used on other apple gadgets as well. The iOS platform is currently being used only on the Apple products, Apple doesn’t permit the use of iOS on third party hardwares.
Apple iOS is a great platform and most of the users don’t take more than 10 minutes to fall in love with it. The iOS is user friendly and provides a very good interface to the user. The multi-touch gestures of iOS are known for stealing the heart of geeks.
As of September 1, 2010, the App Store of Apple contains over 250,000 applications. Those applications are developed for the iOS. The 250,000 applications have been downloaded over 6.5 billion times till September 1, 2010.


Android is an operating system which was developed by Android Inc. This operating system is based on an advanced version of Linux Kernel.
Android operating system is getting quite popular lately. The upcoming Tablet PCs and mobile phones are using Android as the platform. There are several communities of users who develop the applications for Android OS. Currently, there are more than 70,000 applications which are available for Android.
Android OS is picking up the pace and is being used in almost every other upcoming gadget. So, it is believed that Android OS will soon be having many more applications.

Conclusion ..??
I have recently conducted a survey in my college and I came to know that most of the users like the interface of iOS and they believe that iOS is much better. However, there are many more updates which will soon be available for the Android OS.
So, according to the survey about 65% of the geeks are a fan of iOS and find iOS much better than Android. The rest 35% does have faith in Google. So, when it comes to user-friendly interface, iOS is believed to be better than the Android. I have personally used both of them and I found iOS better in terms of multi-touch gestures and friendly interface.
I would love to know about your personal views, which OS do you use and which one of them do you think is better? Use the comment box and share your thoughts with us

Google Launches Google’s ebookstore

Google Editions was expected to release anytime this month. Today, Google’s ebook store goes live with more than 3 million ebooks. Google’s web reader is compatible with the latest version of most of the browsers.
Google account holders can buy ebooks from their mobiles as well and they can access them via mobile itself. Application of the ebook store is available free of cost to the Android and iOS users. So, people can now access their ebooks anywhere with their mobile phones.
Google Editions – http://books.google.com/ebooks

Free Electronic Music

Owning a high end electronic music making programs might make you all the envy of most of your pals, however, you would almost certainly need to mortgage the house to pay for it. Several electronic music making program developers possess reasonable lite-versions of their larger products for the beginning electronic songs composers.

Whenever deciding which electronic music making program to

How Restore Missing Folder without Tools

There is a simple story like this:
"My computer is infected with the virus, after I scan using antivirus, virus was successfully omitted or cleaned, but when after I restart there are several folders on my computer is missing".
"Flash exposed to the virus, after the scan using your antivirus, flash is free from viruses but why when I try opening flasdisk on another computer many folders are missing, has been trying to find the Properties Tools, Folder Options, View, Show Hidden Files and Folders, can seen but to throw the checklist on the attributes would still not be activated? ".
Of the two issues can be concluded that the computers where we work have a virus that berekstensikan. Scr.
how the virus is very simple to change any existing folder on your computer or pendrive to file an application with a doubled capacity to 32 Kb (written when we open). and when tried in the clear use of one of the antivirus vendors, the virus can be removed but the effect was caused by scanning the folders that this virus is lost.
Actually the folder does not disappear but just hidden. And the missing folder can we return with menggukan attrib command at a command prompt.
How very simple but before peeling how to restore the missing folder will we peeled a bit about this attribute.
To view the Properties attribute can be done in two ways:
1. Through the Windows Prompt
2. Through Command Prompt
Command attribute works on DOS command prompt, has several functions one
them is to set the attribute of a file if the file will be given the attribute:
-Read-only file attribute
-Archive file attribute
File-System Attibut
-Hidden File Attribute
To restore the missing folders using the second way is
through the command prompt.
The stages are as follows:
1. Click Start
2. Then select the Run
3. Then type the word cmd
4. Next will come the command prompt
5. Well this is the most important part of our discussion this time, at the command
This prompt we type attrib /? To find out a few commands on
attribute properties through the command prompt.
6. later on it will appear sederatan pompt sentence that describes
about attributes such as:
- Sign (+) for an attribute sets
- Sign (-) for an attribute Clears
- Letter R for read-only file attributes
- The letter A for the Archive file attribute
- The letter S for System file attribute
- The letter H for the Hidden file attribute
- / S for the process of equating the files in previous folders and all subfolders on the computer
- / D for the process to be conducted on the folder itself
7. Back to the Folder missing then we type the command at a command prompt is: (type this command on Drive C:> or D:> or where there is a missing folder.)
attrib-s-h *.* / S / D
8. Next refresh your computer or all the drives in our computers, the result is BAM!, The missing folder reappeared.
So now we do not have to worry anymore with folders lost due to virus attack. Scr. In fact, we can open a folder other people in the hidden .. (Hehe.. But I do not recommend you know ...) good luck.

Did You Know..???? Most sophisticated computer Today...???

Technology world again - again make us amazed with one of the discovery of super-sophisticated computers, you just have the image below!


If you think the above is a set of PEN WITH CAMERA, you are absolutely wrong.
The device above is the set of the new Advanced Super Computer - recently discovered by the Japanese.

Take a look at how these devices work:
How in your opinion? Cool is not it?

So be ready with portable computer or laptop will be obsolete

TIPS for Computer fast and stable

Have not you feel your computer slow? or frequent restart for no apparent reason? This is very annoying, when we work and race against the clock, er even crash your computer ... or even a virus attack and clear-cutting job file .. wah can-can not get a promotion nie. Nakut opening-nakutin yes, computers do need care in order to work optimally. Here are some tips for your computer to work mild optimal and stable. These tips come from my experience and many references in the wilds of the internet. Happy reading! Cleanliness is not just our bodies that must be on guard but must also be kept kebersihanya Computer, the computer restarts itself often because of dust accumulate inside the casing of the CPU. My friend has experienced, at that computer 2 months is not in use, when to use these computers were slow and often restart. After opening its CPU casing was dust in the CPU meets peripherals. After cleaning, the computer is stable and does not restart again. At least every 2 months, open the CPU casing and clean the dust on the fan, motherboard and other peripherals. Remove the RAM and clean the connectors use a dry cloth and wipe all their slots. If you can, remove and replace the processor heatsink thermal pastenya. Dust can cause electrical and data flow is not smooth and when soiling fan / heatsink may interfere with the release of heat, consequently the temperature increased. In fact, thanks to dust, my friend's hard drive is not detected, then the plug was cleaned. To clean the motherboard can use a fine brush and added to the body motherboards for dust disappears. Clean room and equipment around the computer. If the computer is free from dust, then the electric current flow, heat release was smooth and the results form the more stable computer.

WHAT Is Blu-ray Disc...??

Blu-ray Disc (official abbreviation BD) is an optical disc storage medium designed to supersede the DVD format. The format defines as its standard physical media a 12 cm (same as DVDs and CDs), 25 GB per-layer optical disc, with dual layer discs (50 GB) the norm for feature-length video discs and additional layers possible later.

The name Blu-ray Disc refers to the blue laser used to read the disc, which allows for six times more storage than on a DVD. The term Blu was used instead of the correct Blue which is commonly used in English (and therefore not registrable as a trademark).
Blu-ray Disc was developed by the Blu-ray Disc Association, a group representing makers of consumer electronics, computer hardware, and motion pictures. As of June 2009, more than 1,500 Blu-ray Disc titles were available in Australia and the United Kingdom, with 2,500 in the United States and Canada. In Japan as of July 2010 more than 3,300 titles were released.
During the high definition optical disc format war, Blu-ray Disc competed with the HD DVD format. Toshiba, the main company that supported HD DVD, conceded in February 2008,[4] releasing their own Blu-ray Disc player in late 2009.
Blu-ray Disc recordable
Main article: Blu-ray Disc recordable
"Blu-ray Disc recordable" refers to two optical disc formats that can be recorded with an optical disc recorder. BD-Rs can be written to once, whereas BD-REs can be erased and re-recorded multiple times. The current practical maximum speed for Blu-ray Discs is about 12×. Higher speeds of rotation (10,000+ rpm) cause too much wobble for the discs to be read properly, as with the 20× and 52× maximum speeds, respectively, of standard DVDs and CDs.
Since September 2007, BD-RE is also available in the smaller 8 cm Mini Blu-ray Disc size.
On September 18, 2007, Pioneer and Mitsubishi codeveloped BD-R LTH ("Low to High" in groove recording), which features an organic dye recording layer that can be manufactured by modifying existing CD-R and DVD-R production equipment, significantly reducing manufacturing costs.[64] In February 2008, Taiyo Yuden, Mitsubishi, and Maxell released the first BD-R LTH Discs, and in March 2008, Sony's PlayStation 3 gained official support for BD-R LTH Discs with the 2.20 firmware update.[66] In May 2009 Verbatim/Mitsubishi announced the industry's first 6X BD-R LTH media, which allows recording a 25 GB disc in about 16 minutes.
Unlike the previous releases of 120 mm optical discs (i.e., CDs and standard DVDs), Blu-ray recorders hit the market almost simultaneously with Blu-ray's debut.



Source

The 2011 Computer Technology Preview...!

Not surprisingly, the PC ethos we all embrace—nonlinear, flexible, interconnected, and constantly evolving—lies at the center of the crossover. We mean that literally and figuratively. Desktops. Laptops. Tablets. Smartphones. Accelerated Processing Units. 60GHz networks. Personal servers. These days, each of us is essentially walking around with a tiny supercomputer, Internet, and cloud-computing scheme in our hands. To which we say, “Bring it on.” We’ve been waiting for this moment for years.

As always, the near future of PC technology is coalescing around three key axes: performance, power, and interconnectivity. Back in the day, you could sacrifice one or maybe even two of these criteria. Not anymore. Over the next 10 pages, we’re going to explain what, why, when, where, and how
CPUs
2011 will bring a true battle royal for CPU supremacy. Here's an early scouting report

Yeah, we know: Everyone is hyper-excited about netbooks, tablets, smartphones, phablets, and blah blah blah. We couldn’t care less about that noise, because in 2011, we’re going to see an epic battle between AMD’s new CPU, code-named Bulldozer, and Intel’s Sandy Bridge and Sandy Bridge E procs.

We know that Bulldozer will be a significant update for AMD and is considered the company’s first all-out “new” chip since the original Athlon was introduced. The major change is the adoption of a new dual-chip “module” approach. Typical CPU cores are stand-alone affairs, isolated islands. If core 1 is busy on a single-threaded application and core 2 is twiddling its thumbs, core 1 won’t be able to access core 2’s resources. With Bulldozer’s dual-core modules, CPU core resources that aren’t being utilized can be thrown at the single-threaded application core 1 is working on, thereby increasing performance.

Computer Arcitechture

Wow ...LAtest Technology Intel predicts 10GHz chips by 2011

Intel is predicting that its microprocessors will hit 10GHz by the year 2011. In addition, it is currently working on a system bus that is 10 times faster than its upcoming 400 MHz (4*100MHz) Pentium 4 system bus, working at effective speeds of around 4 GHz.

What will we do with all that processor power? Intel is working hard to bring high-end applications to your desktop featuring much more video, speech interaction, and more complex and functional user interfaces.Hopefully, most of you are familiar with Moore's Law, so this doesn't come as a surprise to you. If not, Moore's Law states that the number of transistors in a common microprocessor will double every 18 months. As well, it can be applied to processor speed and many other computing/technology metrics. This law has more or less (no pun intended) held true since the transistor was invented. So, assuming that early 2001 is a time when 1 GHz processors are rampant let's see what we get if we apply Moore's Law:

early 2001: 1 GHz
mid 2002: 2 GHz
early 2004: 4 GHz
mid 2005: 8 GHz
early 2007: 16 GHz
mid 2008: 32 GHz
early 2010: 64 GHz
mid 2011: 128 GHz

This is very interesting indeed. Intel appears to be underestimating progress in 2011 by a full factor of 10. Even by doing that, it's still making headlines with its predictions. Some will call this crazy, but those that yell the loudest have the shortest memories.

Download Free Windows 7 Harry Potter Themes

for you fans of Harry Potter, there is an interesting theme that would want to use to decorate your desktop Windows 7. Of course, the theme this time Windows 7 is Windows 7 Harry Potter theme. This theme is actually already on the Microsoft site betepatan with the release of the latest Harry Potter film Harry Potter 7 or Harry Potter and the Deathly Hallows: Part 1.

The theme of Windows 7 has 6 pieces of wallpaper with resolution of 1920 x 1200 pixels and includes a photo of a character in the Harry Potter movies are: Harry Potter, Hermione Granger, Ron Weasley, Lord Voldemort, Bellatrix Lestrange and Professor Severus Snape. This theme will change the desktop color to black border. Maybe to match the color that dominates in some Harry Potter movie that is black.

Sound scheme used is the cityscape. However, the theme of Windows 7 is not a screen saver. Maybe you can find Harry Potter's own screen saver and add it to this theme to be more fit.

Want to try Windows 7 Harry Potter theme this? Please download directly to the Microsoft site via the link below:

Download Theme Harry Potter

Beware Worm Spread via spam on Facebook and MySpace

Kasperky Lab party security companies warned that the virus makers have created a pair of worm used to attack the users of MySpace and Facebook. Two variants of the latest worm dubbed Koobface, which uses social engineering techniques by utilizing a website as a gateway to infect the victim's computer that would make it part of a botnet network.

When users with computers that have been infected with the worm have access to his MySpace account, then the variant Koobface-A will do a post a link in the "commentaries of friends' that will direct users to clicks to sites that contain malicious programs. While Koobface-B to find the target Facebook users by sending spam messages to any "friends" of Facebook users who have been infected with this virus.

The message reads some subjects such as "Paris Hilton Tosses Dwarf On The Street" or like "Hello, You must see it! LOL. My friend catched you on hidden cam "and others. The message was intended for the candidates newspaper click on the link that will take them to a website that contains video content clips that have been in pairs as a trap.

Potential victims will also receive a message to download the "latest version of Flash Player" but which is actually a file with a name that carries the worm Koobface codesetup.exe.
Alexander Gostev, a senior virus analyst at Kaspersky Lab, said similar attacks could happen in the future. "At the beginning of 2008, we predicted that we would see an increase in cybercriminal who exploit on MySpace, Facebook and several similar websites, and now we have seen the evidence. I believe this is only a modest first step, and the virus makers will continue to look for targets of this source with the intensity increasing, "he said further.

Backup Your drivers with DriverMax

One of the classic problems after reinstalling the drivers, the sound does not appear, the graph fitting broken play games, the printer can not be using that tuk ngeprint. Not to mention when it would have to find cd to install the drivers that were scattered, not even often lost, or forgotten borrowed a friend. Huff tired dech. At this time komputerblog tuk would love a solution to overcome this problem.

DriverMax . Is a free software that works for backing up drivers , with the help of the wizard all the drivers installed on the windows will be backed up automatically in the form of compressed (zipped), if a time is required after re-install, just import the driver then backed up all the drivers that will be installed to the windows system , it was all done in a matter of 5-10 minutes. Great, fast and effective rather than, than have to enter one by one cd drivers, with the help of DriverMax, reinstall does not have to worry anymore about the driver.

DriverMax supports Windows XP, Vista and 7. Features DriverMax , among whom were:

Download driver updates
Backup drivers
Obtain detailed reports about installed components and drivers
Getting hardware information
Can share information on hardware and drivers to a friend
Waiting for, download DriverMax now, and do the backup drivers to watch in the future, may be useful.

Download Drivermax

How Disable hibernation and remove hiberfil.sys

Did you know that Windows has two modes of power management, the first is the Sleep Mode and the second is the Hibernate mode , the Sleep Mode PC / Laptop use minimal power to keep your PC / Laptop in order to stay alive, while Hibernate mode does not utilize the power at all. The difference is in Sleep Mode state of windows is stored in memory while in Hibernate mode state of windows is stored in a file called hiberfil.sys .

The function of both power management is the same, namely to keep the windows where the objec idle, so that when we need the windows in quick time, use the sleep mode / hibernate mode is a wise choice. One of the benefits of hard disk space disable hibernation is a more roomy.

What is hiberfil.sys

It is one of the many windows file system, serves to keep current state (memory) / state of your PC / Laptop, hiberfil.sys located in the root drive of Windows, eg Windows installed on drive C, then the file hiberfil.sys located in c: / hiberfil.sys.

Hiberfil.sys file size depends on how much RAM is installed on a PC / Laptop, the larger the RAM size the greater the hiberfil.sys file. For example, the picture above is the size of the hiberfil.sys my laptop has 2 GB of RAM.

Nonatif Hibernate mode in Windows Vista or 7

To disable hibernation on windows vista or 7 do the following:

Run command prompt with administrator level.




At the command prompt window type:

Powercfg-h off

Voila, now hibernate mode has been disabled.


Nonatifkan Hibernate mode in Windows XP

How to disable Hibernate Mode in Windows XP as follows:

1.Start> Control Panel> Power Options.
2.Select the Hibernate tab, then remove the check mark in Enable hibernation.
3.and select OK.

How Fix NTLDR is missing error on Windows

This article was inspired when i fix my laptop both of my friends, just mention his name's so and so, "kin, the laptop suddenly appeared NTLD is missing , b, suddenly appeared  "," how come ", I replied , "if you know not going to ask the same Kinta: p", "Huff, tired uuhh".

Experience the same thing is also a friend?, Follows the solution.

NTLDR error message

I've found some error message NTLDR, including:

"NTLDR is missing
Press any key to restart "


"NTLDR is missing
Press Ctrl Alt Del to restart "


"Boot: Couldn't find NTLDR
Please insert another disk "

And most often I find is the number 2, " NTLDR is missing, Press Ctrl + Alt + Del to restart ". NTLDR error message occurs after the POST ( Power On Self Test ) is completed or after the process of checking hardware. 

Cause of the error message NTLDR is missing

Based on experience there are several reasons why the NTLDR error message appears, among:

1.PC boot on USB, CD or Hard Drive that has no boot sector .
2.Windows systems have corrupted .
3.There was an error in the boot configuration file.
4.Cables IDE / Sata damaged, so the data does not flow perfectly.
5.The process of upgrading windows is not perfect.

Solutions to improve the error message NTLDR is missing

1.If lucky, simply restart your PC / laptop is missing NTLR message can be lost.
2.Check to see if there is a USB, CD or other media that is connected to a PC / Laptop, if any pull, this is to 3.prevent the boot from the media.
4.Check the BIOS, if the first boot from the Hard Drive that has a boot sector or windows installed in it.
The three methods above is P3Kom me in fixing the NTLDR error, if not then I wear that is always a powerful way, the following steps.

How to fix a powerful message is missing NTLR

1.Prepare and insert the Windows CD into the CD / DVD Drive
2.Restart your PC / Laptop and make for the first boot from the CD / DVD Drive.
3.Press enter on the message " press anykey to boot from CD ".
4.After entering the Setup Menu, press "R" to enter the repair command line .
5.Next will be asked, where the location of windowsnya system, a choice of numbers, select the number that there are windows system, for example: if the C drive then select number 1.
6.Furthermore, we will ask the administrator password, type and enter.
7.Now we will copy the files NTLDR & NTDETECT.com into the system. Eg CD / DVD drives you is drive D, then the command
Copy d: \ i38 \ ntldr c: \
Copy d: \ i38 \ ntdetect.com c: \

If successful it will have the words "2 files copied".
Restart and choose boot from the hard drive first.
Voila PC / Laptop you are healthy again.

Introduction to Android

Android is the operating system Linux-based Mobile Phone. Android is open source source code provided free of charge for developers to create their applications to run on Android.Pada initially, Android is one of Android Inc.-made products., But Google acquired Android Inc.., And all intellectual property owned by Android inc. Google Inc. gained. who later developed a system back Android.mengakuisi Android Inc. ..

As information Android Inc.. are newcomers in terms of making software for mobile phones in Palo Alto, California United States. Then formed the Open Handset Alliance, a consortium of 34 companies hadware, software, and telecommunications, including Google, HTC, Intel, Motorola, Qualcomm, T-Mobile, Nvidia, etc.. Open Handset Alliance was formed to develop its Android-which incidentally is the first OpenSource OS for Mobile Phone.

On November 5, 2007, an early version of Android dirilislah where with the Open Handset Alliance's Android states support the development of open standards on mobile devices. On the other hand, Google released the Android code under the Apache license, a license software and open standard mobile device.

In this world there are two types of distributors operating system Android. The first fully supported by Google or Google Mail Services (GMS) and the second is completely free distribution without direct support Google's otherwise known as the Open Handset Distribution (OHD).

The founders of Android Inc.. working at Google, among them Andy Rubi, Rich Miner, Nick Sears, and Chris White. At that time many consider the functions of Android Inc.. just as software on mobile phones. Since then the rumors that Google is about to enter the mobile phone market

In company Google, a team led by Rubin served to develop a program of mobile devices supported by the Linux kernel. This shows an indication that Google is preparing for a competition in the mobile phone market. until now has many Android phones were present in the market, starting from Google Nexus One, HTC Legend, Sony Ericcson Xperia X10, Samsung Galaxy S and many more.

The advantages of Android include:

1. Openness

Android provides access to basic functions of mobile devices using standard calls to the API.
2. Destruction of the border

You can combine information from the Internet into the phone, such as contact information, or data on the geographical location to get a new chance.
3. Similarity application

To Android is no difference between the main phone application and other software, you can even change the program to dial the number, or screen saver.
4. Quick and easy development

In the SDK has everything you need to create and run Android applications, including this simulator instruments, and advanced debugging tools.
Likens Google's Android as a stack of software. Each layer of this stack to collect a few programs that support specific functions of the operating system. The following is the composition of the layer - the layer when viewed from the base layer to the upper layers:

a. Linux Kernel

Pile at the bottom of this Android is a kernel architecture.

b. Android Runtime

The Linux kernel is a layer after Runtime.Android Android Runtime contains Core Libraries and Dalvik Virtual Machine. Core Libraries includes a set of core Java libraries, which means that Android includes a set of basic libraries that provides most of the functions that exist in the base libraries Java programming language.

c. Libraries

Located at the same level with Android Runtime is Libraries. Android includes a set of libraries in C / C + + which is used by the various components that exist on the Android system.

d. Application Framework

The next layer is the application framework, which includes programs to manage the basic functions of a smartphone. Application Framework is a set of basic tools such as resource allocation smartphones,
phone application, the change between - a process or program, and tracking the physical location of the phone.

e. Application

On the top layer located on the application itself. In this layer you find the basic functions of smartphones such as calling and sending short messages, running a web browser, access the contact list,
and others. For the average user, this is the layer most often they access. They access the basic functions through the user interface.

Hopefully helpful

Source image:

dailysocial.net, zdnet.com

Repair CD/DVD ROOM and Troubleshoting

Meet again with thelurunk, the troubleshooting section, this time we will explore completely around the CD / DVD Rom, the problem of CD / DVD ROM, how to treat a CD / DVD Rom though durable, etc., monitoring continues, hopefully troubleshooting CD / DVD Rom is useful.
CD / DVD Rom will not read

Clean the head CD / DVD Rom

cd cleaner
Often I find the question, Kinta kok mas CD / DVD Rom I can not read? even though I just bought 2-3 months ago, the first question I ask is whether headnya ever cleaned?, emang ya need cleaning?, yes need lah. Head on CD / DVD Rom have the same functions as the eyes, if the head / eye dirty then our vision will blurry or unclear, as well as head CD / DVD Rom, the laser beam generated by the head can be blocked by dust which resulted in reading the CD / DVD so it is not smooth. The solution, buy a cleaning CD / DVD Rom, usually equipped with alcohol, how easy life, if not allowed to comment below.
Clean the CD / DVD

Often I find that the surface of CDs / DVDs are fat or old prints of hands, this really makes a CD / DVD Rom will be broken, because the head will be forced to read the CD / DVD, therefore, before the CD / DVD is inserted into the drive, make sure free dirty and fat. To clean the fat or old prints of the hand can use the cd cleaners are sold in computer stores.

CD / DVD Rom will not eject
Ever have a CD / DVD jams do not want removed from the drive?, Of course dong, if this happens, it's easy aja, grab a paper clip, and then while pressing the eject button, enter and press the small hole located on the drive CD / DVD rom. voila, success is not.

Microsoft Releases Research Site HTML5

Microsoft Support to technology HTML5 in the Internet Explorer browser look more seriousness. The software giant also released a special site for development research mengkajikan technology to provide easy access for web developers HTML5 Labs.
Through the site, Microsoft provides the code of the developed prototype technology that can be tested for the developers. Currently there are two prototypes are available, namely the Web Sockets and IndexedDB, two parts of HTML5 are not yet fully completed perfected.
"The prototype, this prototype will help us discuss with the developer community, and provide implementation experience with the draft specification that will generate feedback to improve standards in the end," said Jean Paoli, general manager of Microsoft's Interoperability Strategy, Wednesday (22/12 / 2010).
Web Sockets is a way for elements of web pages to communicate with the server continuously without visitors to refresh. This technology can be used on a website, server, or application clients and servers. Meanwhile, IndexedDB allows website visitors to save data on your computer to be accessible offline, eg for bookmarks or e-mail.
"We chose these two specifications from the beginning because of the potential use of large, but not yet stable enough," says Paoli. Many components of HTML5 already invested in Microsoft's latest browser is still beta, Internet Explorer 9 Beta.

Hiding IP Address By SwitchProxy

Sometimes you need to make your IP address is not visible, for the safety of your computer network. If you want your IP address is not visible, you can use the SwitchProxy. Add-on for Firefox allows you to monitor and change from a few different proxy settings with ease. You also can use the add-on is as Anonymizer to protect your computer from outside interference.

We all know that using more than one proxy in the normal way is very tiring because we must continuously monitor all of them. With SwitchProxy you can manage all proxy that you use very easily. Add-on also provides a feature to insert, edit, or remove a proxy with a few clicks away. To use a proxy, you just need to select from the list and click Apply.

Anonymizer features provided by SwitchProxy use some proxy fruit were randomly changed within a certain interval. This feature is very useful for people who want to protect their computer from hackers or other parties.

Here's how to make your IP address is not visible by using the SwitchProxy:

The first thing you need to do of course is to download and install the add-on SwitchProxy this.

After the add-on installed, click the Add button, then select the Anonymous of configuration options available, and click Next.

In the next window, you can add a proxy list that you want to use either manually or through a proxy list. You can then give a name for this configuration to facilitate its subsequent use, then click Save.

You can find free proxy lists from this page .

To begin to hide your IP address, you must choose MyProxy from the toolbar, then click Apply. Now that you've hidden the IP address. Very easy is not it?

Conducting Remote Desktop Connection With TeamViewer

We can control a computer remotely, using certain software and Internet networks. The problem is, most software requires a lot of settings that are technical and too complicated. However, the software is now available that can help you control your computer remotely with very easily.


TeamViewer is a software that allows us to do desktop sharing over the Internet. We can control our partner computer located elsewhere, and do things. All this is very easy to do, and even we do not need to bother with things that are technical, such as firewalls, IP addresses, or NAT.

Indeed we can find many similar software, but TeamViewer provides solutions for all types of needs. TeamViewer is very simple and easy to use. We do not even need to install it first. We just need to run this software on our computers, and of course on the computer that we want to control from afar.

We can do many things with the help of TeamViewer. For example, we can show our desktop to our partners, and share product demos, presentations, and so forth. We also can use TeamViewer to control a server.
TeamViewer also provides additional features that are very useful, for example, file transfer feature, which allows us to copy the files and folders between our computers with our partners computer.

We can download and use TeamViewer free of charge, provided for non-commercial purposes. On his official website www.TeamViewer.com available several versions of TeamViewer, which TeamViewer full version, as well as several other versions for more specific purposes, such as to provide customer service, to control the server, and so forth.

Disable Autorun On USB

In the flash disc exposed to the virus usually (not always) there autorun.info file that contains commands to run the virus program. Well, when the flash disc is inserted into the USB drive its autorun feature not be disabled then Windows will automatically run programs at background without a confirmation to the user .

One way to reduce the risk of contracting the virus is to disable the autorun feature on the USB drive. There is also the way is as follows:



1.Click the Start button - Run.
2.Type gpedit.msc and press OK.
3.Click on User Configuration - Administrative Templates - System .
4.Click 2x on the Turn Off Autoplay .
5.Click on the option Enable .
6.At the option Turn off Autoplay on , select All drives .
7.Click OK.
8.Done.

Trusting Password: Network Authentication

Aspects of network security is closely related to the services provided: inbound or outbound. Security on outbound service can be best pursued with firewall configuration. Similarly, with anonymous access inbound servicing, such as anonymous FTP, HTTP, Gopher, etc.. In this case, intentionally provided information for everyone. Another case when we want to provide a non-anonymous access (or authenticated services), where other than through a firewall, someone who is requesting access must also get a 'permission' server after first proving his identity. This is the authentication. Furthermore, the authors use the term as a synonym for the word autentisasi.

RISK-SECURITY SERVICE INBOUND
Why should autentisasi ... ..? The Internet is a public network, and is open to everyone all over the world to join. Once the size of this network, have caused profits and losses. Often we hear and read about bobolnya bank financial computer systems, the Pentagon classified information or data bases students' academic transcripts. The sentence is adequate to represent the statement that we should be 'vigilant' against those 'evil' and always try to minimize the possibility for them to be able to perform his evil intentions. It's easy to exclude the possibility of infiltration (illegal access) from the outside by closing all inbound traffic channel service to the internal network. But this means has reduced the main advantages of the network: communication and the use of shared resources (sharing resources). Thus, a natural consequence with a large enough network, is to accept and try to minimize this risk, not destroy.


We will start from a network-administrator (NA), which has done a good job, in preparing the 'defense' for all services, inbound outbound and anonymous. Need some additional things that should be remembered again. Whether the defense is strong enough for the theft of the relationship (hijacking attack)? What is in it already considered the possibility of illegal monitoring of information packets are sent (packet sniffing - playback attack)? Or is it included readiness to actually illegal access within the system (false authentication)?

Hijacking usually occurs on computers that contact our network, although for some rare cases, can occur at any point in its path. So it is sensible to consider granting the trust a NA of access, only from computers that most do not have the same security system or perhaps more 'strong', compared with the network under its responsibilities. Business minimize the chances of this tragedy, can also be done by adjusting the packet-filter well or use a server modifications. For example, we can provide anonymous-FTP facility for any computer anywhere, but authenticated-FTP is only given to those hosts listed in the list of 'trust'. Hijacking the middle of the path can be avoided with the use of encryption between networks (end to end encryption).

Confidentiality of data and passwords is also the topic of security design. Programs that are dedicated to packet-sniffing can automatically display the contents of each packet of data between client and server. Password protection of such crimes can be done with the implementation of single-use passwords (non-reusable passwords), so that although they could be monitored by the sniffer, the password can not be used again.

The risk of hijacking and sniffing data (not the password) can not be avoided altogether. This means that NA should consider this possibility and perform optimization for the smaller its chance. Restricted number of accounts with full access and remote access time, is one form of optimization.

MECHANISM AUTENTISASI
Subject autentisasi is proof. Evidenced includes three categories: something about us (something you are lignin), something we know (something you know SYK), and something that we have (something you have SYH). Lignin is closely related to the field of biometrics, such as examination-finger prints, retinal eye examination, voice analysis, etc.. SYK is identical with the password. As for SYH commonly used identity cards such as smartcard. \

Perhaps, that is still widely used is air-password system. To avoid password theft and illegal use of the system, it is sensible to our network system equipped with a disposable passwords. How can the application of this method?

First, using time-stamp system unencrypted. In this way, the new password is sent after the first modified based on the current time. Second, using a challenge-response system (CR), where the password that we give depends on the challenge from the server. Roughly we prepare a list of answers (response) is different for the 'questions' (challenge), which differ by the server. Because of course it was hard to memorize a few tens or hundreds of passwords, it would be easier if the memorized rule is to change the challenge provided a response (so not random). For example, our rule is: "kapitalkan fifth letter and delete the fourth letter", then the password that we provide is MxyPtlk1W2 to challenge Mxyzptlk1W2 system.

If the CR system, must be known 'aturan' it, then the time-stamp system, we must remember the password for the provision of these time-stamps. Does not make it this way? How lucky these mechanisms are generally handled by a device, either software or hardware. Kerberos, autentisasi software created at MIT and adopt a time-stamp system, require modifications to the client for time synchronization with the server as well as giving a stamp-time passwords. Modify the client program reminds us of the proxy and indeed, more or less like that. CR systems are usually applied at the same time with hardware support. Examples of operational CR system is a device SNK-004 card (Digital Pathways) that can be applied in conjunction with packet-FWTK TIS (Trusted Information Systems - Internet Firewall Toolkit).

TIS-FWTK offer a solution to single-use passwords (the CR) that 'fun': S / Key. S / Key hash algorithms iteratively apply the procedure to a seed, so the system can validate-client instant response but did not have the ability to predict response-next client. So if there is an intrusion on the system, there is no 'something' that can be stolen (usually a list of passwords). Hash algorithms have two main properties. First, the input can not be regenerated from the output (non-reversible). Second, there are two possible inputs for a same output.

ENCRYPTION AND Cryptography
Cryptography has evolved a long time, when people want information that he sent not to 'read' by parties not interested. Traditionally known as the two mechanisms cryptography, private key or public key. DES (data encryption standard) used by Kerberos to use private-key system. RSA (Rivest Shamir Addleman) implement public-key system. One of the contributors RSA, Ron Rivest and then make MD4 (message digest function # 4) which is used by S / Key his TIS-FWTK. Optimization and crossbreed between the two traditional methods are giving birth PGP (Pretty Good Privacy). Discussion of the DES, RSA, or PGP is a separate book and not in place is disclosed here. But clearly, the private-key system is characterized by the encrypt-decrypt the keys are identical, while the public-key systems, this process is done with two keys: public key to encrypt and decrypt secret key for this key which both generated and have relationships close through a mathematical algorithm. Because the mathematical processes required in advance, the speed of public-key systems can be thousands of times slower than equivalent private-key algorithm, although on the other hand offers better protection. The exploitation of the advantages and disadvantages of public and private key system is PGP, which is done for data transmission-private key system with the session-key so that it runs fast, while the transmission of session-key of his own using public-key.

With encryption, the information we send to a network through another network of safety doubts (the Internet), relatively more secure. Encryption between networks is causing a 'thief' must try a little harder to get illegal information he expected. There are several opportunities for the implementation of encryption, namely: at the application level, data-link level and network level.
Application-level encryption requires the use of client-server software special. In accordance with the OSI reference model, encryption of data-link is only valid for point to point connection, such as encryption system on a phone modem. While encryption network level (network layer) is applied on the router or other equipment adjacent to the tissue on both sides. Optimization of the interests and security policies carried out by adjusting the type / part of the IP packet to be encrypted, adjustments to the firewall architecture and, consequently, the effectiveness of key distribution, encryption, etc.. In the future, where technology VLAN (Virtual LAN) is estimated to be the primary choice for Intranet (enterprisewide), the use of network-level encryption has become so important. Perhaps equally important to state that while a company is 'forced' to use the internet as a route for transmission of sensitive information between the central office with other branches dibelahan earth.

TIS-FWTK Kerberos and Authentication Server
Kerberos is one of the works of Athena project, a collaboration between MIT, IBM and DEC. Kerberos was designed for supporting autentisasi and encryption of data in a distributed environment through modification of standards of client or server. Some operating system vendors have included Kerberos into their products. MIT itself provides for free many versions of Unix that has been in-Kerberizing. Even for the interests ported to the operating system or client-server software that does not support Kerberos, MIT provides its source-code, also is free. Project Athena Kerberos itself implement in many applications such as NFS, rlogin, email, and system passwords. Secure RPC (Sun Microsystems) also implements the same thing.

There are several things to consider in the implementation of Kerberos. Modification of the client and server software will cause the restriction application options. Unfortunately there are no alternative methods as a substitute for source-code modification (as in a proxy that allows custom user procedure or custom client software). Then, most people also agreed to call: "Kerberos is relatively difficult to implement / manage".

The package offered by systems other autentisasi TIS-FWTK: authentication-server. This server is designed in a modular, flexible mechanism that supports many popular autentisasi as standard reusable password system, S / Key, SecurdID card from Security Dynamics (systems with time-stamps), card-004 Digital Pathways SNK (CR system) and ease of integration new mechanism. Back to the conversation at the beginning of this writing, if our primary interest is how to prepare the 'defense' for non-anonymous inbound service, perhaps the authentication-server is a solution worth considering. Why? How does this system work? Not much space in this paper to load all our discussions about autentisasi, but the cover illustration below will give some idea for your interest in network security, concerning the authentication-server.

Author: Eueung Mulyana & Onno W. Purbo