What are exFAT, NTFS and FAT File Systems? What is the difference and which one you should USE?

What are exFAT, NTFS and FAT File Systems? What is the difference and which one you should USE?

Introduction to File System:

In computer, file system is a system, used to store data into memory or to retrieve the data. Well, what happens when we do not follow the system rules? Why are we using file-system? The answer to all those questions is to arrange data in a specific pattern in memory which will let you to access the data easily. By separating data into pieces and giving each piece a name, would make it easy to find the data. The piece of data is called file and to manage these files with certain rules and logics called file system. There are many kind of systems each one has different properties, structure, logic, security, size and more. File systems can be used on numerous storage devices one of the common storage device which follow these logics is the HDD (Hard Disk). Other kinds of Medias  which use file system are flash memories, magnetic tapes, SD cards and Optical discs.

File Systems:

There need an interface between file systems and the OS. This interface can be textual such as CLI or graphical such as GUI. If graphical then folder, sub directories containing documents files or nested folders are often used.

• FAT (File Allocation Table)

FAT file system is supported by almost all operating systems for personal computers including Windows. Over years, the system has expanded from FAT 12 to FAT 16 and FAT 32. It was introduced in 1977 with Standalone Disk Basic-80. However, since the system has been in use for so long, it also comes with a certain limitations. While they might not been a problem when the system was first introduced, after all these years, the drawbacks seem serious. Individual files have an upper limit of 4 GB on the FAT 32 system. A partition formatted with FAT32 has a limit of 8TB which might not be too big of a problem now, but it is noticed by more heavy duty users. FAT file systems are the default file systems for removable media except CDs and DVDs. FAT 12 was suitable only for floppy discs, FAT 16, and FAT 32 are suitable for higher data storage devices.

2

•     NTFS (New Technology File System)

For many purposes, the NTFS file system is superior to FAT in terms of features and reliability. It was introduced with Windows NT OS in 1993 allowed ACL based permissions. An Access Control List (ACL) is list of permissions attach to an object, in short which users or system processes are granted to access objects , as well what operations (read, write, read/write, hidden ) are allowed to perform on objects. Other features supported by NTFS are encryption, compression, multiple file streams etc.

3

• exFAT (Extended File Allocation Table)

exFAT is a Microsoft file system introduced in 2006 for the optimization of flash memories such as USB flash drives and SD Cards. exFAT has been adobted by SD Card Association as default file system for Security Digital Extended Card (SDXC) cards larger than 32 GiB.

Like NTFS, this format too supports a large file and disk partition size limits therefore, you can surpass the 4 GB limit of the previous system. Being an upgrade over FAT 32 system, this is an obvious option to enjoy the benefits of the exFAT file system without the limitations. It is also compatible with NTFS, works with every available version of Windows as well as Mac OS. On Linux, if you find it not working by default, there are software available to enable compatibility.

What is a Keylogger

What is a Keylogger Software?

What is a keylogger?

A keylogger or simply keystroke logger is an application software or surveillance software which records keystrokes in order to get unauthenticated access to a computer. Keylogger stores the keystrokes in a file and sends it back to the receiver, when victim is connected to the internet.

Why use keylogger?

Keylogger can be used for various purposes it can be used to attack a user, to steal it account passwords, records of financial transactions or by large IT companies to tackle network and other technical problems. Families and business people use keyloggers to monitor network usage, without their user’s knowledge. It can also be used to monitor human interactions with computer.

Pros and Cons of a Keylogger

A keylogger can be used in various ways some would use it in negative way for instance to record personal transactions and some would use it to monitor their user’s interactions with computer. Following are the main pros and cons of a keylogger

Pros        &  Cons                                                                                                                                 

•   Monitor Network Usage                              
•   Ensure security of People especially by security agencies using keyloggers
•   Record Financial Transactions covertly
•   Steal personal passwords
• Monitor human interactions
•   Personal Data is uploaded to a website unknowingly.
•   Can enable remote login to the local machine from web.

Keyloggers (Software-Based)

Most of viral Keylogging techniques are given bellow:

•  Memory Injection: In this logging a hardware device is connected to your system which accesses directly into memory. The technique is generally use to bypass UAC (User Access Controls).
• JavaScript Keylogging: A malicious script tag is added to webpage which listens to key events such as document.write()
•   Form Grab Keylogging: This type of keylogger grabs data entered into forms <forms>--</forms> tags from webpages.
• Kernel Keylogging: software which resides in the kernel of OS and intercepts the keystrokes that pass through kernel. These keyloggers are the most difficult to detect keyloggers because they reside in kernel which a user barely knows.

Fight Back (Countermeasures)

• On-Screen-keyboard: Counter measures are not specific, means there effectiveness varies because there are different techniques of Keylogging. Every technique requires a different counter measure. In case of win10, win 8 or win7 windows on screen keyboard is a counter measure to avoid keyloggers but it cannot defeat all the keyloggers such as kernel based and screenloggers. 
•  
•  Anti keylogger: An anti-keylogger is a type of software designed to detect keyloggers. These software have the ability to immobilize hidden keystroke loggers. It scans all the files of computer against a database of keyloggers looking for similarities which might signal the presence of a keylogger.
• Live CD: A live CD (live CD or live Discs contains a complete bootable installation of operating system which runs from CD-ROM not from the hard disk). If bootable CD is clean of viruses and is updated patch then it will upgrade your system files and remove old ones.
•  Anti-Virus: Most of the antiviruses are designed to clean software based keyloggers however some of anti-virus programs are unable to detect them because keylogger is  legitimate software code
•  Speech Recognition: Speech-text-Recognition can also be used to avoid keyloggers. They convert your voice into text without touching any key button.
• Hand Writing Recognition: Stylus movements are also very fruitful in immobilizing keyloggers. Light pens are also suitable.

 A keylogger example of a screen capture, which holds potentially confidential and private information. The image below holds the corresponding keylogger text result.

 A log file from a software-based keylogger, based on the screen capture above.