Understanding Encryption

Encrypting data is a good way to protect sensitive information. It ensures that the data can only be read by the person who is authorized to have access to it. 

What is encryption?

In very basic terms, encryption is a way to send a message in code. The only person who can decode the message is the person with the correct key; to anyone else, the message looks like a random series of letters, numbers, and characters. Encryption is especially important if you are trying to send sensitive information that other people should not be able to access. Because email messages are sent over the internet and might be intercepted by an attacker, it is important to add an additional layer of security to sensitive information.

How is it different from digital signatures?

Like digital signatures, public-key encryption utilizes software such as PGP, converts information with mathematical algorithms, and relies on public and private keys, but there are differences:

• The purpose of encryption is confidentiality—concealing the content of the message by translating it into a code. The purpose of digital signatures is integrity and authenticity—verifying the sender of a message and indicating that the content has not been changed. Although encryption and digital signatures can be used independently, you can also sign an encrypted message.
• When you sign a message, you use your private key, and anybody who has your public key can verify that the signature is valid. When you encrypt a message, you use the public key for the person you're sending it to, and his or her private key is used to decrypt the message. Because people should keep their private keys confidential and should protect them with passwords, the intended recipient should be the only one who is able to view the information.

How does encryption work?

1. Obtain the public key for the person you want to be able to read the information. If you get the key from a public key ring, contact the person directly to confirm that the series of letters and numbers associated with the key is the correct fingerprint.
2. Encrypt the email message using their public key. Most email clients have a feature to easily perform this task.
3. When the person receives the message, he or she will be able to decrypt it.

Understanding Digital Signatures

Digital signatures are a way to verify that an email message is really from the person who supposedly sent it and that it hasn't been changed. 

What is a digital signature?

There are different types of digital signatures; this tip focuses on digital signatures for email messages. You may have received emails that have a block of letters and numbers at the bottom of the message. Although it may look like useless text or some kind of error, this information is actually a digital signature. To generate a signature, a mathematical algorithm is used to combine the information in a key with the information in the message. The result is a random-looking string of letters and numbers.

Why would you use one?

Because it is so easy for attackers and viruses to "spoof" email addresses, it is sometimes difficult to identify legitimate messages. Authenticity may be especially important for business correspondence—if you are relying on someone to provide or verify information, you want to be sure that the information is coming from the correct source. A signed message also indicates that changes have not been made to the content since it was sent; any changes would cause the signature to break.

How does it work?

Before you can understand how a digital signature works, there are some terms you should know:

• Keys - Keys are used to create digital signatures. For every signature, there is a public key and a private key.
  • Private key - The private key is the portion of the key you use to actually sign an email message. The private key is protected by a password, and you should never give your private key to anyone.
  • Public key - The public key is the portion of the key that is available to other people. Whether you upload it to a public key ring or send it to someone, this is the key other people can use to check your signature. A list of other people who have signed your key is also included with your public key. You will only be able to see their identities if you already have their public keys on your key ring.
• Key ring - A key ring contains public keys. You have a key ring that contains the keys of people who have sent you their keys or whose keys you have gotten from a public key server. A public key server contains keys of people who have chosen to upload their keys.
• Fingerprint - When confirming a key, you will actually be confirming the unique series of letters and numbers that comprise the fingerprint of the key. The fingerprint is a different series of letters and numbers than the chunk of information that appears at the bottom of a signed email message.
• Key certificates - When you select a key on a key ring, you will usually see the key certificate, which contains information about the key, such as the key owner, the date the key was created, and the date the key will expire.
• "Web of trust" - When someone signs your key, they are confirming that the key actually belongs to you. The more signatures you collect, the stronger your key becomes. If someone sees that your key has been signed by other people that he or she trusts, he or she is more inclined to trust your key. Note: Just because someone else has trusted a key or you find it on a public key ring does not mean you should automatically trust it. You should always verify the fingerprint yourself.

The process for creating, obtaining, and using keys is fairly straightforward:

1. Generate a key using software such as PGP, which stands for Pretty Good Privacy, or GnuPG, which stands for GNU Privacy Guard.
2. Increase the authenticity of your key by having your key signed by co-workers or other associates who also have keys. In the process of signing your key, they will confirm that the fingerprint on the key you sent them belongs to you. By doing this, they verify your identity and indicate trust in your key.
3. Upload your signed key to a public key ring so that if someone gets a message with your signature, they can verify the digital signature.
4. Digitally sign your outgoing email messages. Most email clients have a feature to easily add your digital signature to your message.

There are a variety of mechanisms for creating digital signatures, and these mechanisms may operate differently. For example, S/MIME does not add a visible block of letters and numbers within the message, and its digital signatures are verified indirectly using a certificate authority instead of directly with other users in a web of trust. You may just see an icon or note on the message that the signature has been verified. If you get an error about a digital signature, try to contact the sender through a phone call or a separate email address that you know is valid to verify the authenticity of the message.

Coordinating Virus and Spyware Defense

Using anti-virus and anti-spyware software is an important part of cyber security. But in an attempt to protect yourself, you may unintentionally cause problems. 

Isn't it better to have more protection?

Spyware and viruses can interfere with your computer's ability to process information or can modify or destroy data. You may feel that the more anti-virus and anti-spyware programs you install on your computer, the safer you will be. It is true that not all programs are equally effective, and they will not all detect the same malicious code. However, by installing multiple programs in an attempt to catch everything, you may introduce problems.

How can anti-virus or anti-spyware software cause problems?

It is important to use anti-virus and anti-spyware software. But too much or the wrong kind can affect the performance of your computer and the effectiveness of the software itself.
Scanning your computer for viruses and spyware uses some of the available memory on your computer. If you have multiple programs trying to scan at the same time, you may limit the amount of resources left to perform your tasks. Essentially, you have created a denial of service against yourself. It is also possible that in the process of scanning for viruses and spyware, anti-virus or anti-spyware software may misinterpret the virus definitions of other programs. Instead of recognizing them as definitions, the software may interpret the definitions as actual malicious code. Not only could this result in false positives for the presence of viruses or spyware, but the anti-virus or anti-spyware software may actually quarantine or delete the other software.

How can you avoid these problems?

• Investigate your options in advance - Research available anti-virus and anti-spyware software to determine the best choice for you. Consider the amount of malicious code the software recognizes, and try to find out how frequently the virus definitions are updated. Also check for known compatibility issues with other software you may be running on your computer.
• Limit the number of programs you install - Many vendors are now releasing packages that incorporate both anti-virus and anti-spyware capabilities together. However, if you decide to choose separate programs, you really only need one anti-virus program and one anti-spyware program. If you install more, you increase your risk for problems.
• Install the software in phases - Install the anti-virus software first and test it for a few days before installing anti-spyware software. If problems develop, you have a better chance at isolating the source and then determining if it is an issue with the software itself or with compatibility.
• Watch for problems - If your computer starts processing requests more slowly, you are seeing error messages when updating your virus definitions, your software does not seem to be recognizing malicious code, or other issues develop that cannot be easily explained, check your anti-virus and anti-spyware software.

Browsing Safely: Understanding Active Content and Cookies

Many people browse the Internet without much thought to what is happening behind the scenes. Active content and cookies are common elements that may pose hidden risks when viewed in a browser or email client. 

What is active content?

To increase functionality or add design embellishments, web sites often rely on scripts that execute programs within the web browser. This active content can be used to create "splash pages" or options like drop-down menus. Unfortunately, these scripts are often a way for attackers to download or execute malicious code on a user's computer.

• JavaScript - JavaScript is just one of many web scripts (other examples are VBScript, ECMAScript, and JScript) and is probably the most recognized. Used on almost every web site now, JavaScript and other scripts are popular because users expect the functionality and "look" that it provides, and it's easy to incorporate (many common software programs for building web sites have the capability to add JavaScript features with little effort or knowledge required of the user). However, because of these reasons, attackers can manipulate it to their own purposes. A popular type of attack that relies on JavaScript involves redirecting users from a legitimate web site to a malicious one that may download viruses or collect personal information.
• Java and ActiveX controls - Different from JavaScript, Java and ActiveX controls are actual programs that reside on your computer or can be downloaded over the network into your browser. If executed by attackers, untrustworthy ActiveX controls may be able to do anything on your computer that you can do (such as running spyware and collecting personal information, connecting to other computers, and potentially doing other damage). Java applets usually run in a more restricted environment, but if that environment isn't secure, then malicious Java applets may create opportunities for attack as well.

JavaScript and other forms of active content are not always dangerous, but they are common tools for attackers. You can prevent active content from running in most browsers, but realize that the added security may limit functionality and break features of some sites you visit. Before clicking on a link to a web site that you are not familiar with or do not trust, take the precaution of disabling active content. These same risks may also apply to the email program you use. Many email clients use the same programs as web browsers to display HTML, so vulnerabilities that affect active content like JavaScript and ActiveX often apply to email. Viewing messages as plain text may resolve this problem.

What are cookies?

When you browse the Internet, information about your computer may be collected and stored. This information might be general information about your computer (such as IP address, the domain you used to connect (e.g., .edu, .com, .net), and the type of browser you used). It might also be more specific information about your browsing habits (such as the last time you visited a particular web site or your personal preferences for viewing that site). Cookies can be saved for varying lengths of time:

• Session cookies - Session cookies store information only as long as you're using the browser; once you close the browser, the information is erased. The primary purpose of session cookies is to help with navigation, such as by indicating whether or not you've already visited a particular page and retaining information about your preferences once you've visited a page.
• Persistent cookies - Persistent cookies are stored on your computer so that your personal preferences can be retained. In most browsers, you can adjust the length of time that persistent cookies are stored. It is because of these cookies that your email address appears by default when you open your Yahoo! or Hotmail email account, or your personalized home page appears when you visit your favorite online merchant. If an attacker gains access to your computer, he or she may be able to gather personal information about you through these files.

To increase your level of security, consider adjusting your privacy and security settings to block or limit cookies in your web browser. To make sure that other sites are not collecting personal information about you without your knowledge, choose to only allow cookies for the web site you are visiting; block or limit cookies from a third-party. If you are using a public computer, you should make sure that cookies are disabled to prevent other people from accessing or using your personal information.

Recognizing and Avoiding Spyware

Because of its popularity, the internet has become an ideal target for advertising. As a result, spyware, or adware, has become increasingly prevalent. When troubleshooting problems with your computer, you may discover that the source of the problem is spyware software that has been installed on your machine without your knowledge. 

 What is spyware?

Despite its name, the term "spyware" doesn't refer to something used by undercover operatives, but rather by the advertising industry. In fact, spyware is also known as "adware." It refers to a category of software that, when installed on your computer, may send you pop-up ads, redirect your browser to certain web sites, or monitor the web sites that you visit. Some extreme, invasive versions of spyware may track exactly what keys you type. Attackers may also use spyware for malicious purposes. Because of the extra processing, spyware may cause your computer to become slow or sluggish. There are also privacy implications:

• What information is being gathered?
• Who is receiving it?
• How is it being used?

How do you know if there is spyware on your computer?

The following symptoms may indicate that spyware is installed on your computer:

• you are subjected to endless pop-up windows
• you are redirected to web sites other than the one you typed into your browser
• new, unexpected toolbars appear in your web browser
• new, unexpected icons appear in the task tray at the bottom of your screen
• your browser's home page suddenly changed
• the search engine your browser opens when you click "search" has been changed
• certain keys fail to work in your browser (e.g., the tab key doesn't work when you are moving to the next field within a form)
• random Windows error messages begin to appear
• your computer suddenly seems very slow when opening programs or processing tasks (saving files, etc.)

How can you prevent spyware from installing on your computer?

To avoid unintentionally installing it yourself, follow these good security practices:

• Don't click on links within pop-up windows - Because pop-up windows are often a product of spyware, clicking on the window may install spyware software on your computer. To close the pop-up window, click on the "X" icon in the titlebar instead of a "close" link within the window.
• Choose "no" when asked unexpected questions - Be wary of unexpected dialog boxes asking whether you want to run a particular program or perform another type of task. Always select "no" or "cancel," or close the dialog box by clicking the "X" icon in the titlebar.
• Be wary of free downloadable software - There are many sites that offer customized toolbars or other features that appeal to users. Don't download programs from sites you don't trust, and realize that you may be exposing your computer to spyware by downloading some of these programs.
• Don't follow email links claiming to offer anti-spyware software - Like email viruses, the links may serve the opposite purpose and actually install the spyware it claims to be eliminating.

As an additional good security practice, especially if you are concerned that you might have spyware on your machine and want to minimize the impact, consider taking the following action:

• Adjust your browser preferences to limit pop-up windows and cookies - Pop-up windows are often generated by some kind of scripting or active content. Adjusting the settings within your browser to reduce or prevent scripting or active content may reduce the number of pop-up windows that appear. Some browsers offer a specific option to block or limit pop-up windows. Certain types of cookies are sometimes considered spyware because they reveal what web pages you have visited. You can adjust your privacy settings to only allow cookies for the web site you are visiting.

How do you remove spyware?

• Run a full scan on your computer with your anti-virus software - Some anti-virus software will find and remove spyware, but it may not find the spyware when it is monitoring your computer in real time. Set your anti-virus software to prompt you to run a full scan periodically.
• Run a legitimate product specifically designed to remove spyware - Many vendors offer products that will scan your computer for spyware and remove any spyware software. Popular products include Lavasoft's Ad-Aware, Microsoft's Window Defender, Webroot's SpySweeper, and Spybot Search and Destroy.
• Make sure that your anti-virus and anti-spyware software are compatible - Take a phased approach to installing the software to ensure that you don't unintentionally introduce problems.

Recovering from Viruses, Worms, and Trojan Horses

Unfortunately, many users are victims of viruses, worms, or Trojan horses. If your computer gets infected with malicious code, there are steps you can take to recover. 

How do you know your computer is infected?

Unfortunately, there is no particular way to identify that your computer has been infected with malicious code. Some infections may completely destroy files and shut down your computer, while others may only subtly affect your computer's normal operations. Be aware of any unusual or unexpected behaviors. If you are running anti-virus software, it may alert you that it has found malicious code on your computer. The anti-virus software may be able to clean the malicious code automatically, but if it can't, you will need to take additional steps.

What can you do if you are infected?

1. Minimize the damage - If you are at work and have access to an IT department, contact them immediately. The sooner they can investigate and clean your computer, the less damage to your computer and other computers on the network. If you are on your home computer or a laptop, disconnect your computer from the internet. By removing the internet connection, you prevent an attacker or virus from being able to access your computer and perform tasks such as locating personal data, manipulating or deleting files, or using your computer to attack other computers.
2. Remove the malicious code - If you have anti-virus software installed on your computer, update the virus definitions (if possible), and perform a manual scan of your entire system. If you do not have anti-virus software, you can purchase it at a local computer store. If the software can't locate and remove the infection, you may need to reinstall your operating system, usually with a system restore disk that is often supplied with a new computer. Note that reinstalling or restoring the operating system typically erases all of your files and any additional software that you have installed on your computer. After reinstalling the operating system and any other software, install all of the appropriate patches to fix known vulnerabilities.

How can you reduce the risk of another infection?

Dealing with the presence of malicious code on your computer can be a frustrating experience that can cost you time, money, and data. The following recommendations will build your defense against future infections:

• use and maintain anti-virus software - Anti-virus software recognizes and protects your computer against most known viruses. However, attackers are continually writing new viruses, so it is important to keep your anti-virus software current.
• change your passwords - Your original passwords may have been compromised during the infection, so you should change them. This includes passwords for web sites that may have been cached in your browser. Make the passwords difficult for attackers to guess.
• keep software up to date - Install software patches so that attackers can't take advantage of known problems or vulnerabilities. Many operating systems offer automatic updates. If this option is available, you should enable it.
• install or enable a firewall - Firewalls may be able to prevent some types of infection by blocking malicious traffic before it can enter your computer. Some operating systems actually include a firewall, but you need to make sure it is enabled.
• use anti-spyware tools - Spyware is a common source of viruses, but you can minimize the number of infections by using a legitimate program that identifies and removes spyware.
• follow good security practices - Take appropriate precautions when using email and web browsers so that you reduce the risk that your actions will trigger an infection.

As a precaution, maintain backups of your files on CDs or DVDs so that you have saved copies if you do get infected again.

Understanding Hidden Threats: Corrupted Software Files

Malicious code is not always hidden in web page scripts or unusual file formats. Attackers may corrupt types of files that you would recognize and typically consider safe, so you should take precautions when opening files from other people. 

What types of files can attackers corrupt?

An attacker may be able to insert malicious code into any file, including common file types that you would normally consider safe. These files may include documents created with word processing software, spreadsheets, or image files. After corrupting the file, an attacker may distribute it through email or post it to a web site. Depending on the type of malicious code, you may infect your computer by just opening the file.

When corrupting files, attackers often take advantage of vulnerabilities that they discover in the software that is used to create or open the file. These vulnerabilities may allow attackers to insert and execute malicious scripts or code, and they are not always detected. Sometimes the vulnerability involves a combination of certain files (such as a particular piece of software running on a particular operating system) or only affects certain versions of a software program.

What problems can malicious files cause?

There are various types of malicious code, including viruses, worms, and Trojan horses. However, the range of consequences varies even within these categories. The malicious code may be designed to perform one or more functions, including

• interfering with your computer's ability to process information by consuming memory or bandwidth (causing your computer to become significantly slower or even "freeze")
• installing, altering, or deleting files on your computer
• giving the attacker access to your computer
• using your computer to attack other computers.

How can you protect yourself?

Use and maintain anti-virus software - Anti-virus software recognizes and protects your computer against most known viruses, so you may be able to detect and remove the virus before it can do any damage. Because attackers are continually writing new viruses, it is important to keep your definitions up to date.

Use caution with email attachments - Do not open email attachments that you were not expecting, especially if they are from people you do not know. If you decide to open an email attachment, scan it for viruses first. Not only is it possible for attackers to "spoof" the source of an email message, but your legitimate contacts may unknowingly send you an infected file.

Be wary of downloadable files on web sites - Avoid downloading files from sites that you do not trust. If you are getting the files from a supposedly secure site, look for a web site certificate. If you do download a file from a web site, consider saving it to your computer and manually scanning it for viruses before opening it.

Keep software up to date - Install software patches so that attackers cannot take advantage of known problems or vulnerabilities. Many operating systems offer automatic updates. If this option is available, you should enable it.

Take advantage of security settings - Check the security settings of your email client and your web browser. Apply the highest level of security available that still gives you the functionality you need

Dealing with Cyberbullies

Bullies are now taking advantage of technology to intimidate and harass their victims. Dealing with cyberbullying can be difficult, but there are steps you can take. 

What is cyberbullying?

Cyberbullying refers to the new, and growing, practice of using technology to harass, or bully, someone else. Bullies used to be restricted to methods such as physical intimidation, postal mail, or the telephone. Now, developments in electronic media offer forums such as email, instant messaging, web pages, and digital photos to add to the arsenal. Computers, cell phones, and PDAs are new tools that can be applied to an old practice.
Forms of cyberbullying can range in severity from cruel or embarrassing rumors to threats, harassment, or stalking. It can affect any age group; however, teenagers and young adults are common victims, and cyberbullying is a growing problem in schools.

Why has cyberbullying become such a problem?

The relative anonymity of the internet is appealing for bullies because it enhances the intimidation and makes tracing the activity more difficult. Some bullies also find it easier to be more vicious because there is no personal contact. Unfortunately, the internet and email can also increase the visibility of the activity. Information or pictures posted online or forwarded in mass emails can reach a larger audience faster than more traditional methods, causing more damage to the victims. And because of the amount of personal information available online, bullies may be able to arbitrarily choose their victims.

Cyberbullying may also indicate a tendency toward more serious behavior. While bullying has always been an unfortunate reality, most bullies grow out of it. Cyberbullying has not existed long enough to have solid research, but there is evidence that it may be an early warning for more violent behavior.

How can you protect yourself?

• Be careful where you post personal information - By limiting the number of people who have access to your contact information or details about your interests, habits, or employment, you reduce your exposure to bullies that you do not know. This may limit your risk of becoming a victim and may make it easier to identify the bully if you are victimized.
• Avoid escalating the situation - Responding with hostility is likely to provoke a bully and escalate the situation. Depending on the circumstances, consider ignoring the issue. Often, bullies thrive on the reaction of their victims. Other options include subtle actions. For example, if you are receiving unwanted email messages, consider changing your email address. If the bully does not have access to the new address, the problem may stop. If you continue to get messages at your new account, you may have a stronger case for legal action.
• Document the activity - Keep a record of any online activity (emails, web pages, instant messages, etc.), including relevant dates and times. In addition to archiving an electronic version, consider printing a copy.
• Report cyberbullying to the appropriate authorities - If you are being harassed or threatened, report the activity to the local authorities. Law enforcement agencies have different policies, but your local police department or FBI branch are good starting points. Unfortunately, there is a distinction between free speech and punishable offenses, but the legal implications should be decided by the law enforcement officials and the prosecutors. Depending on the activity, it may also be appropriate to report it to school officials who may have separate policies for dealing with activity that involves students.

Protect your children by teaching them good online habits. Keep lines of communication open with your children so that they feel comfortable telling you if they are being victimized online. Reduce their risk of becoming cyberbullies by setting guidelines for and monitoring their use of the internet and other electronic media (cell phones, PDAs, etc.).

Guidelines for Publishing Information Online

Remember that the internet is a public resource. Avoid putting anything online that you don't want the public to see or that you may want to retract. 

Why is it important to remember that the internet is public?

Because the internet is so accessible and contains a wealth of information, it has become a popular resource for communicating, for researching topics, and for finding information about people. It may seem less intimidating than actually interacting with other people because there is a sense of anonymity. However, you are not really anonymous when you are online, and it is just as easy for people to find information about you as it is for you to find information about them. Unfortunately, many people have become so familiar and comfortable with the internet that they may adopt practices that make them vulnerable. For example, although people are typically wary of sharing personal information with strangers they meet on the street, they may not hesitate to post that same information online. Once it is online, it can be accessed by a world of strangers, and you have no idea what they might do with that information.

What guidelines can you follow when publishing information on the internet?

• View the internet as a novel, not a diary - Make sure you are comfortable with anyone seeing the information you put online. Expect that people you have never met will find your page; even if you are keeping an online journal or blog, write it with the expectation that it is available for public consumption. Some sites may use passwords or other security restrictions to protect the information, but these methods are not usually used for most websites. If you want the information to be private or restricted to a small, select group of people, the internet is probably not the best forum.
• Be careful what you advertise - In the past, it was difficult to find information about people other than their phone numbers or address. Now, an increasing amount of personal information is available online, especially because people are creating personal web pages with information about themselves. When deciding how much information to reveal, realize that you are broadcasting it to the world. Supplying your email address may increase the amount of spam you receive. Providing details about your hobbies, your job, your family and friends, and your past may give attackers enough information to perform a successful social engineering attack.
• Realize that you can't take it back - Once you publish something online, it is available to other people and to search engines. You can change or remove information after something has been published, but it is possible that someone has already seen the original version. Even if you try to remove the page(s) from the internet, someone may have saved a copy of the page or used excerpts in another source. Some search engines "cache" copies of web pages; these cached copies may be available after a web page has been deleted or altered. Some web browsers may also maintain a cache of the web pages a user has visited, so the original version may be stored in a temporary file on the user's computer. Think about these implications before publishing information—once something is out there, you can't guarantee that you can completely remove it.

As a general practice, let your common sense guide your decisions about what to post online. Before you publish something on the internet, determine what value it provides and consider the implications of having the information available to the public. Identity theft is an increasing problem, and the more information an attacker can gather about you, the easier it is to pretend to be you. Behave online the way you would behave in your daily life, especially when it involves taking precautions to protect yourself.

Outlaws of Technology! Hacker or Cracker

In order to study the comparison the between the hackers and crackers, it is important to understand the respective definitions. While apparently the words hacking and cracking seems synonymous, yet there exist certain points of distinctions between the two and the meaning of the words will always be heated topics of debate.

Since the very dawn of the civilization, man's hunger to attain the unattainable have went on opening new horizons in almost every aspects of life, and the technology is of no exception to this nature of human.

Aims of Hackers and Crackers

The computer hackers actually trespass or circumvent artistically, yet scientifically into the other computer system with a hunger to know the programmable systems, how they perform and their internal structures, while cracking is slight different in sense. Cracking means to break off the computer's security system. This is a subject matter of hard-core science with an aesthetic undertone of artistic skill that has attracted a few millions of teenagers and young adults all over the world.

Who Is A Hacker And What Is His Aim?

Delving deep into the concepts, we can compare the hackers and crackers. A hacker is a person who commits the fraudulent act or the penal offense of exploring into the other computers in order to know the details of the programmable system and how they work. On the other level, a cracker is a person just more secretive as compared to the hacker. The cracker breaks through the system's security and proves to be far more dangerous than the hackers who just quench his or her thirst by simply discovering the workings of a system.

Hence the crackers can potentially be much more perilous as compared to the hackers. While it is often believed that the hacking is simply exploring into the other computer system with an intention to know how the programmable system works, which is not a fraudulent task unless any sort of vandalism and theft is done by this, another huge section stands strictly against the view and look at the act from the view point of a crime.

Who is A Cracker and What Is His Aim?

A cracker is a technical person who has mastered the art of breaking systems, often not for acquiring knowledge, by the dint of few programs and softwares used as tools. They are more interested in the system's security without the need of great deal of knowledge, thereby not benefiting much.

On the other hand, a hacker who cracks and hacks systems is not only interested in breaking the security of the system but also in knowing about the system's details, by which he gains much more than by simply cracking systems. Unlike a cracker, a hacker generally does not have intention destroy data maliciously or to steel things.

A cracker who is often termed to be a cyber burglar brings out significant harm to the network or steels the information like passwords or credit card numbers. A Trojan is capable enough to recognize and record even every single keystroke that you make. Hence even if you do not store any personal or financial records in your system, the hackers can still be able to obtain the information by recognizing the keystrokes


 Posted by Mr.Shrinath Dagabaj

Real-World Warnings Keep You Safe Online

Many of the warning phrases you probably heard from your parents and teachers are also applicable to using computers and the internet. 

Why are these warnings important?

Like the real world, technology and the internet present dangers as well as benefits. Equipment fails, attackers may target you, and mistakes and poor judgment happen. Just as you take precautions to protect yourself in the real world, you need to take precautions to protect yourself online. For many users, computers and the internet are unfamiliar and intimidating, so it is appropriate to approach them the same way we urge children to approach the real world.

What are some warnings to remember?

• Don't trust candy from strangers - Finding something on the internet does not guarantee that it is true. Anyone can publish information online, so before accepting a statement as fact or taking action, verify that the source is reliable. It is also easy for attackers to "spoof" email addresses, so verify that an email is legitimate before opening an unexpected email attachment or responding to a request for personal information.
• If it sounds too good to be true, it probably is - You have probably seen many emails promising fantastic rewards or monetary gifts. However, regardless of what the email claims, there are not any wealthy strangers desperate to send you money. Beware of grand promises—they are most likely spam, hoaxes, or phishing schemes. Also be wary of pop-up windows and advertisements for free downloadable software—they may be disguising spyware.
• Don't advertise that you are away from home - Some email accounts, especially within an organization, offer a feature (called an autoresponder) that allows you to create an "away" message if you are going to be away from your email for an extended period of time. The message is automatically sent to anyone who emails you while the autoresponder is enabled. While this is a helpful feature for letting your contacts know that you will not be able to respond right away, be careful how you phrase your message. You do not want to let potential attackers know that you are not home, or, worse, give specific details about your location and itinerary. Safer options include phrases such as "I will not have access to email between [date] and [date]." If possible, also restrict the recipients of the message to people within your organization or in your address book. If your away message replies to spam, it only confirms that your email account is active. This may increase the amount of spam you receive.
• Lock up your valuables - If an attacker is able to access your personal data, he or she may be able to compromise or steal the information. Take steps to protect this information by following good security practices. Some of the most basic precautions include locking your computer when you step away; using firewalls, anti-virus software, and strong passwords; installing appropriate software updates; and taking precautions when browsing or using email.
• Have a backup plan - Since your information could be lost or compromised (due to an equipment malfunction, an error, or an attack), make regular backups of your information so that you still have clean, complete copies. Backups also help you identify what has been changed or lost. If your computer has been infected, it is important to remove the infection before resuming your work. Keep in mind that if you did not realize that your computer was infected, your backups may also be compromised.

Safeguarding Your Data

When there are multiple people using your computer and/or you store sensitive personal and work-related data on your computer, it is especially important to take extra security precautions. 

Why isn't "more" better?

Maybe there is an extra software program included with a program you bought. Or perhaps you found a free download online. You may be tempted to install the programs just because you can, or because you think you might use them later. However, even if the source and the software are legitimate, there may be hidden risks. And if other people use your computer, there are additional risks.
These risks become especially important if you use your computer to manage your personal finances (banking, taxes, online bill payment, etc.), store sensitive personal data, or perform work-related activities away from the office. However, there are steps you can take to protect yourself.

How can you protect both your personal and work-related data?

• Use and maintain anti-virus software and a firewall - Protect yourself against viruses and Trojan horses that may steal or modify the data on your own computer and leave you vulnerable by using anti-virus software and a firewall. Make sure to keep your virus definitions up to date.
• Regularly scan your computer for spyware - Spyware or adware hidden in software programs may affect the performance of your computer and give attackers access to your data. Use a legitimate anti-spyware program to scan your computer and remove any of these files. Many anti-virus products have incorporated spyware detection.
• Keep software up to date - Install software patches so that attackers cannot take advantage of known problems or vulnerabilities. Many operating systems offer automatic updates. If this option is available, you should turn it on.
• Evaluate your software's settings - The default settings of most software enable all available functionality. However, attackers may be able to take advantage of this functionality to access your computer. It is especially important to check the settings for software that connects to the internet (browsers, email clients, etc.). Apply the highest level of security available that still gives you the functionality you need.
• Avoid unused software programs - Do not clutter your computer with unnecessary software programs. If you have programs on your computer that you do not use, consider uninstalling them. In addition to consuming system resources, these programs may contain vulnerabilities that, if not patched, may allow an attacker to access your computer.
• Consider creating separate user accounts - If there are other people using your computer, you may be worried that someone else may accidentally access, modify, and/or delete your files. Most operating systems (including Windows XP and Vista, Mac OS X, and Linux) give you the option of creating a different user account for each user, and you can set the amount of access and privileges for each account. You may also choose to have separate accounts for your work and personal purposes. While this approach will not completely isolate each area, it does offer some additional protection. However, it will not protect your computer against vulnerabilities that give an attacker administrative privileges. Ideally, you will have separate computers for work and personal use; this will offer a different type of protection.
• Establish guidelines for computer use - If there are multiple people using your computer, especially children, make sure they understand how to use the computer and internet safely. Setting boundaries and guidelines will help to protect your data.
• Use passwords and encrypt sensitive files - Passwords and other security features add layers of protection if used appropriately.  By encrypting files, you ensure that unauthorized people can't view data even if they can physically access it. You may also want to consider options for full disk encryption, which prevents a thief from even starting your laptop without a passphrase. When you use encryption, it is important to remember your passwords and passphrases; if you forget or lose them, you may lose your data.
• Follow corporate policies for handling and storing work-related information - If you use your computer for work-related purposes, make sure to follow any corporate policies for handling and storing the information. These policies were likely established to protect proprietary information and customer data, as well as to protect you and the company from liability. Even if it is not explicitly stated in your corporate policy, you should avoid allowing other people, including family members, to use a computer that contains corporate data.
• Dispose of sensitive information properly - Simply deleting a file does not completely erase it. To ensure that an attacker cannot access these files, make sure that you adequately erase sensitive files.
• Follow good security habits 

Good Security Habits

There are some simple habits you can adopt that, if performed consistently, may dramatically reduce the chances that the information on your computer will be lost or corrupted. 

How can you minimize the access other people have to your information?

You may be able to easily identify people who could, legitimately or not, gain physical access to your computer—family members, roommates, co-workers, members of a cleaning crew, and maybe others. Identifying the people who could gain remote access to your computer becomes much more difficult. As long as you have a computer and connect it to a network, you are vulnerable to someone or something else accessing or corrupting your information; however, you can develop habits that make it more difficult.

• Lock your computer when you are away from it. Even if you only step away from your computer for a few minutes, it's enough time for someone else to destroy or corrupt your information. Locking your computer prevents another person from being able to simply sit down at your computer and access all of your information.
• Disconnect your computer from the Internet when you aren't using it. The development of technologies such as DSL and cable modems have made it possible for users to be online all the time, but this convenience comes with risks. The likelihood that attackers or viruses scanning the network for available computers will target your computer becomes much higher if your computer is always connected. Depending on what method you use to connect to the Internet, disconnecting may mean disabling a wireless connection, turning off your computer or modem, or disconnecting cables. When you are connected, make sure that you have a firewall enabled.
• Evaluate your security settings. Most software, including browsers and email programs, offers a variety of features that you can tailor to meet your needs and requirements. Enabling certain features to increase convenience or functionality may leave you more vulnerable to being attacked. It is important to examine the settings, particularly the security settings, and select options that meet your needs without putting you at increased risk. If you install a patch or a new version of the software, or if you hear of something that might affect your settings, reevaluate your settings to make sure they are still appropriate.

What other steps can you take?

Sometimes the threats to your information aren't from other people but from natural or technological causes. Although there is no way to control or prevent these problems, you can prepare for them and try to minimize the damage.

• Protect your computer against power surges and brief outages. Aside from providing outlets to plug in your computer and all of its peripherals, some power strips protect your computer against power surges. Many power strips now advertise compensation if they do not effectively protect your computer. Power strips alone will not protect you from power outages, but there are products that do offer an uninterruptible power supply when there are power surges or outages. During a lightning storm or construction work that increases the odds of power surges, consider shutting your computer down and unplugging it from all power sources.
• Back up all of your data. Whether or not you take steps to protect yourself, there will always be a possibility that something will happen to destroy your data. You have probably already experienced this at least once— losing one or more files due to an accident, a virus or worm, a natural event, or a problem with your equipment. Regularly backing up your data on a CD or network reduces the stress and other negative consequences that result from losing important information. Determining how often to back up your data is a personal decision. If you are constantly adding or changing data, you may find weekly backups to be the best alternative; if your content rarely changes, you may decide that your backups do not need to be as frequent. You don't need to back up software that you own on CD-ROM or DVD-ROM—you can reinstall the software from the original media if necessary.

Debunking Some Common Myths

There are some common myths that may influence your online security practices. Knowing the truth will allow you to make better decisions about how to protect yourself. 

How are these myths established?

There is no one cause for these myths. They may have been formed because of a lack of information, an assumption, knowledge of a specific case that was then generalized, or some other source. As with any myth, they are passed from one individual to another, usually because they seem legitimate enough to be true.

Why is it important to know the truth?

While believing these myths may not present a direct threat, they may cause you to be more lax about your security habits. If you are not diligent about protecting yourself, you may be more likely to become a victim of an attack.

What are some common myths, and what is the truth behind them?

• Myth: Anti-virus software and firewalls are 100% effective.
  Truth: Anti-virus software and firewalls are important elements to protecting your information. However, neither of these elements are guaranteed to protect you from an attack. Combining these technologies with good security habits is the best way to reduce your risk.
• Myth: Once software is installed on your computer, you do not have to worry about it anymore.
  Truth: Vendors may release updated versions of software to address problems or fix vulnerabilities. You should install the updates as soon as possible; some software even offers the option to obtain updates automatically. Making sure that you have the latest virus definitions for your anti-virus software is especially important.
• Myth: There is nothing important on your machine, so you do not need to protect it.
  Truth: Your opinion about what is important may differ from an attacker's opinion. If you have personal or financial data on your computer, attackers may be able to collect it and use it for their own financial gain. Even if you do not store that kind of information on your computer, an attacker who can gain control of your computer may be able to use it in attacks against other people.
• Myth: Attackers only target people with money.
  Truth: Anyone can become a victim of identity theft. Attackers look for the biggest reward for the least amount of effort, so they typically target databases that store information about many people. If your information happens to be in the database, it could be collected and used for malicious purposes. It is important to pay attention to your credit information so that you can minimize any potential damage.
• Myth: When computers slow down, it means that they are old and should be replaced.
  Truth: It is possible that running newer or larger software programs on an older computer could lead to slow performance, but you may just need to replace or upgrade a particular component (memory, operating system, CD or DVD drive, etc.). Another possibility is that there are other processes or programs running in the background. If your computer has suddenly become slower, it may be compromised by malware or spyware, or you may be experiencing a denial-of-service attack.

Browsing Safely: Understanding Active Content and Cookies

Many people browse the Internet without much thought to what is happening behind the scenes. Active content and cookies are common elements that may pose hidden risks when viewed in a browser or email client. 

 What is active content?

To increase functionality or add design embellishments, web sites often rely on scripts that execute programs within the web browser. This active content can be used to create "splash pages" or options like drop-down menus. Unfortunately, these scripts are often a way for attackers to download or execute malicious code on a user's computer.

• JavaScript - JavaScript is just one of many web scripts (other examples are VBScript, ECMAScript, and JScript) and is probably the most recognized. Used on almost every web site now, JavaScript and other scripts are popular because users expect the functionality and "look" that it provides, and it's easy to incorporate (many common software programs for building web sites have the capability to add JavaScript features with little effort or knowledge required of the user). However, because of these reasons, attackers can manipulate it to their own purposes. A popular type of attack that relies on JavaScript involves redirecting users from a legitimate web site to a malicious one that may download viruses or collect personal information.
• Java and ActiveX controls - Different from JavaScript, Java and ActiveX controls are actual programs that reside on your computer or can be downloaded over the network into your browser. If executed by attackers, untrustworthy ActiveX controls may be able to do anything on your computer that you can do (such as running spyware and collecting personal information, connecting to other computers, and potentially doing other damage). Java applets usually run in a more restricted environment, but if that environment isn't secure, then malicious Java applets may create opportunities for attack as well.

JavaScript and other forms of active content are not always dangerous, but they are common tools for attackers. You can prevent active content from running in most browsers, but realize that the added security may limit functionality and break features of some sites you visit. Before clicking on a link to a web site that you are not familiar with or do not trust, take the precaution of disabling active content. These same risks may also apply to the email program you use. Many email clients use the same programs as web browsers to display HTML, so vulnerabilities that affect active content like JavaScript and ActiveX often apply to email. Viewing messages as plain text may resolve this problem.

What are cookies?

When you browse the Internet, information about your computer may be collected and stored. This information might be general information about your computer (such as IP address, the domain you used to connect (e.g., .edu, .com, .net), and the type of browser you used). It might also be more specific information about your browsing habits (such as the last time you visited a particular web site or your personal preferences for viewing that site). Cookies can be saved for varying lengths of time:

• Session cookies - Session cookies store information only as long as you're using the browser; once you close the browser, the information is erased. The primary purpose of session cookies is to help with navigation, such as by indicating whether or not you've already visited a particular page and retaining information about your preferences once you've visited a page.
• Persistent cookies - Persistent cookies are stored on your computer so that your personal preferences can be retained. In most browsers, you can adjust the length of time that persistent cookies are stored. It is because of these cookies that your email address appears by default when you open your Yahoo! or Hotmail email account, or your personalized home page appears when you visit your favorite online merchant. If an attacker gains access to your computer, he or she may be able to gather personal information about you through these files.

To increase your level of security, consider adjusting your privacy and security settings to block or limit cookies in your web browser. To make sure that other sites are not collecting personal information about you without your knowledge, choose to only allow cookies for the web site you are visiting; block or limit cookies from a third-party. If you are using a public computer, you should make sure that cookies are disabled to prevent other people from accessing or using your personal information.