Учебное пособие состоит из двух частей и англо-русского словаря. Материалом для пособия послужило американское издание для изучающих компьютер P. Norton "Introduction to Computers"
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- Бұл бет үшін навигация:
- E-mail Viruses
- Macro Viruses
- Viruses That Do Not Require Attachments
- Protecting Yourself
UNIT 8. Information Security
Protecting Your Online PrivacyInformation about our private lives is available to a degree unimaginable just a few years ago. With the Internet's explosion in popularity, people are revealing more about themselves than ever before. Some examples follow: If you purchase an item over the World Wide Web, you not only provide the seller with your e-mail address but you often include your credit card number. Many e-commerce Web sites also request other personal information, such as telephone numbers and mailing addresses. Many Web sites that offer special services, such as travel planning, job hunting, or car buying require clients to complete forms that store vast amounts of information about them. If you post a message to an Internet newsgroup or participate in a chat room discussion, you reveal your e-mail address and interests to anyone who happens to be in the group at that time. As an online consumer, you leave a trail of information about yourself wherever you go. This trail can be followed by marketers, spammers, hackers, and thieves right back to your PC--or even to your doorstep. There is not a lot you can do after your information has fallen into the wrong hands. You can take measures, however, to prevent too many people from getting that information, especially if you use the Internet or an online service regularly. Here are some tips that can help: Avoid Being Added to Mailing Lists. When you fill out a warranty, subscription, or registration form – either on paper or online – make sure it includes an option that prevents your information from being added to a mailing list. If the option is available, check it; if it is not, do not return the form. If there is any doubt, contact the organization and learn its policies regarding mailing lists. Make Online Purchases Only Through Secure Web Sites. Before you purchase anything over the Internet, make sure that the transaction is secure. You can protect your privacy in two ways. First, if you use a current browser, such as Internet Explorer 5.0 or Netscape Navigator 5.0, the browser can tell you whether the server is secure. Check your browser's security settings before proceeding with a transaction. Second, check the vendor's Web site to see whether you have the option to switch to a secure server before making the transaction. If this option is available, take it. Never Assume That Your E-Mail Is Private. Watch what you say, especially when using your company's or school's e-mail system. Never respond to an unsolicited e-mail message, especially if you do not recognize the sender. Be Careful When Posting to Newsgroups. Many Internet newsgroups and chat rooms are unsupervised. If you post a message to a group, your e-mail address and interests can make you easy prey for spammers and pranksters. Before posting a message to any group, watch the group for a few days to determine whether its users are trustworthy. Try to find out if the group is supervised by a system operator and get that person's address, if possible. Don't Flame. An online argument can have disastrous results. There are many documented cases of ISPs being shut down by spam as a result of a flame--a critical or insulting message--posted by one of the ISP's users. This practice can result in a loss of online privacy and in your Internet service being cut off by the ISP. Resist the urge to be critical or argumentative online. E-mail VirusesUntil recently, it was not considered possible to spread viruses within e-mail messages. Because e-mail messages are predominantly text, they could not carry viruses, which require executable code to run. Newer-generation e-mail programs, however, support e-mail messages in various formats, including HTML. They also support attachments – you can attach a file (such as a DOC, EXE, or other binary file) to a message and send it to a recipient, who can open the file on receiving it. These features of e-mail programs have made them more convenient and useful. However, both features have also opened the door to new types of viruses – e-mail viruses –which can be devastating to anyone who receives them. Macro VirusesThe more common type of e-mail virus called a macro virus relies on a file attached to the message. To create an e-mail virus, the programmer selects a popular application that has a macro language, such as Microsoft Word or Lotus 1-2-3. Then he or she creates a document in that application and places a macro within the document. The macro can contain commands that perform various tasks, including copying and deleting files, changing system settings, creating new e-mail messages, and more. Finally, the programmer attaches the document containing the macro code to an e-mail message and sends the file to one or more unsuspecting recipients. When a recipient downloads the attachment and opens it, the macro in the file runs automatically. Once released, the virus looks for the recipient's e-mail address book and sends copies of the infected attachment to people in the address book. The virus may also remain on the first recipient's machine and do considerable damage, like a regular virus. A newer and more frightening breed of e-mail virus does not require an attached file to inflict damage. Viruses That Do Not Require AttachmentsThis type of virus can reside directly within the text of an HTML-format e-mail message, in unseen code and written in a programming language such as Visual Basic Script (VBScript). The first known virus of this type called "BubbleBoy" was transmitted in November 1999. Although the virus did not become widespread, it aroused a new sense of urgency in development and antivirus communities. To become infected with the BubbleBoy virus, the recipient did not have to do anything; it was enough simply to receive the infected message. On restarting the computer, the user activates the virus code and the virus makes changes to the Windows Registry settings and sends copies of the infected e-mail message to everyone in the recipient's address book. Protecting YourselfUnlike other types of viruses, there may not be much you can do to protect yourself from e-mail viruses, but you should take the following precautions: Do not open e-mail attachments from people you do not know. Install a reputable antivirus program, run it frequently, and keep its virus definitions up to date. Some experts suggest using two different antivirus programs and running them on an alternating schedule. Check your Web browser, e-mail program, and newsreader and make sure that their security settings are set to the highest possible level. In addition, you may want to set your e-mail program not to accept messages delivered in HTML format. Be alert to new developments in viruses by periodically checking virus-related sites on the Web. These sites are hosted by the makers of antivirus programs, universities, and security experts. жүктеу/скачать 0,7 Mb. Достарыңызбен бөлісу:
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