In order to effectively protect your system you need to take pro-active guard as well as take preventive measures. In this article, you will learn about methods of data encryption to protect existing data from unauthorised users and you will also learn about taking care of your data against virus attacks.

Symmetric Encryption

Symmetric encryption, also known as secret key encryption, is a type of encryption which focuses on the data encryption standard (DES) process. Algorithms that are used with the latest encryption methods, like Rijndael for example, are different from DES method. At the same time, there are a number of similarities that the two methods have in common.

By understanding symmetric encryption, you will be able to make wiser decisions when implementing data encryption. The first thing you should note is that there is not much need to learn about the internals of encryption, and the reason for this is because most classes conceal the mathematical complexities which comprise them.

This means that developers get to focus on the most important issue, which is the protection of the key. While knowing how to use any given piece of technology is very important, having some knowledge of how this technology actually works can assist you in making decisions which enhance performance, and this is especially true with encryption.

Overall, the concept of encryption is relatively simple: you protect data so that unauthorized people cannot access it. The most basic way to accomplish this is through the use of computers. The reason for this is because data within computers will be represented with both 1’s and 0’s, and if you can shuffle around the bits, you can make it harder for people to gain access to data they should not see.

While those familiar with encryption will agree that this is an overly simplified definition of encryption, however, the key with encryption is the "shuffler." In addition to this, encryption will replace the bits based on substitution tables which are preset.

DES (Data Encryption Standard)

DES is perhaps one of the oldest forms of encryption in the world which is computer based. It was created by IBM during the late 1970s, and most consider it breakable due to the fact it is small in size (only 56 bits). While the algorithm was broken in the late 1990s, it took using a machine which was dedicated to this task, and the machine cost $250,000. In addition to this, it took the machine three days just to finally crack it. While DES is breakable, it takes a lot effort to break it.

While less effort would be needed today, DES is still pretty difficult to crack, but it can still be used depending on the level of security you need, as well as the importance of the data you want to secure. It is challenging to discuss the gritty details of encryption without getting into mathematical terms.  First off, no matter how complex an algorithm may appear, one thing that you have to keep in mind is that encryption basically involves shuffling.

The first thing you will want to do is create a text input which is plain, and split it into blocks which are 64 bits in size. The reason for this is because DES is an encryption method which is block based, and the blocking is very important. The encryption key would be 16 sub keys which have a length of 48 bits. This is also based on shuffling. When every subkey that is generated, the previous sub key will be split in half, and the bits for each half will be moved to the left(one bit only at a time). The first bits will be encased around the end.

The two fresh halves will be rejoined to showcase a newer key. The 56 bit key that you offer for the encryption method will only be used for creating the first sub key, and will not be used directly to encrypt the data. After the plain text has been broken down into a collection of 64 bit blocks, it will be shuffled (via a process called permutation), which is dependent on the known shuffle table that defines how the bits can be shuffled. This means that bit 1 can be placed within bit 40, while bit 2 can be placed within bit 23. You should note that this does not really make the encryption more secure.

Actually, it makes the method more challenging when it comes to utilizing an algorithm which is software based. After the shuffle has been completed, the bits will be transferred through a group of 16 steps, which may also be known as rounds, and this is done through the use of 16 sub keys which are generated. The 64 bits which were shuffled earlier are passed to the round, and here it is broken down into twin blocks which are 32 bits each, and they are processed in opposition to the corresponding key for this round.

Protect Your System Against Viruses

A computer virus is a bit of code that has been specifically designed to infect computers. Once the virus enters your computer, it can effect your files in various ways. While some viruses are relatively harmless, others are extremely dangerous, because they can either damage or eliminate your data, and if this data is sensitive, the consequences can be devastating.

Computer viruses can compromise the security of your entire system. A number of studies have indicated that there are as many as 10,000 computer viruses in existence, but since more are being created on a regular basis, it is likely that this data is old. If you use a computer that is connected to the Internet, the chances of you getting a computer virus are dramatically high. In fact, the only way to truly prevent yourself from getting a virus is to not be connected to the Internet at all, and be wary of what media you place in your system.

Unfortunately, most of us do not have that option. The Internet has become an important part of our lives, and disconnecting from it simply to avoid viruses is not very wise. At the same time, a number of studies have indicated that as many as 60% of computer users have no anti virus software installed. This means that a virus can easily spread in the systems of most people, and they can get the viruses via email attachments, bulletin boards, or downloads. The good news about computer viruses is that there are a number of things you can do to protect yourself from them.

How Computer Viruses Function

Like its real world counterpart, the computer virus will replicate itself once it enters a system. While viruses may differ from one another, the one thing they all have in common is this: to replicate and spread to every area of a system, taking it over completely. Once a computer has become infected with a virus, if you save any file to your desk, there is a good chance that the virus will get on this disk, and can infect the computer of anyone who uses it. It is basically a vicious cycle. There are many unscrupulous people that make a hobby out of creating computer viruses, and understanding how your system is exposed to them can stop you from becoming a victim.

A virus can be written into virtually any file, so this is the first thing that you should know about them. This is especially true for when you install software on your system. There are many cases in which viruses where inadvertently added to licensed software, but most of the time, you are safe when handling licensed software, since you purchased it through legitimate channels. There are two basic ways in which a virus can enter a system, and this is either through external media that is introduced to it(such as floppy disks, zip drives, CDs, or DVDs), or via the Internet.

It is also possible to get a virus through an email attachment, but I should note that it is not possible for a virus to be put in the main text of an email, so simply opening an email will not cause your system to get infected. One myth which is frequently made about viruses is that the only way they can enter your system is through executable program files, which come with the designation .exe. Some also believe that viruses can’t be activated unless certain programs are launched. However, macro viruses prove these myths to be wrong, since they can reside in any application that utilizes the macro language.

How to Prevent and Eliminate Viruses

As with real world viruses, when it comes to computer viruses, prevention is a lot better than the cure. Taking the necessary steps to stop viruses from entering your system is a lot easier than getting rid of them once they are present. The first step in preventing computer viruses is to install anti-virus software. While there are people who are computer savvy and do not need an anti-virus software to protect their systems, unless you fall under this category, you will want to get anti-virus software. This software is either really cheap, and some versions may be offered for free. The software will conduct daily scans of your system, and will immediately notify you should it detect or find a virus.

Other methods of preventing viruses include being careful where you surf on the web, and being cautious with what you download. Some, though not all adult sites are known for being sources of not only spyware, but viruses as well. If you like using P2P software, or filesharing networks, again, many viruses are circulated in these sources. Avoid opening email attachments from any email which comes from an unknown source, and be sure to keep your anti-virus software updated at all times. Because viruses are being created regularly, your anti-virus software should update itself at least once per day.