Theshiva: antivirus

Welcome to RAV AntiVirus Online Virus Scan!

Welcome to RAV AntiVirus Online Virus Scan! Here you can scan and clean free of charge your PC of viruses and other malwares! Virus infections really happen on your home computer as well as at the office. To protect permanently your computer of viruses, Trojans or worms, you may want to consider testing or acquiring a RAV AntiVirus commercial product. All RAV AntiVirus products are also available as fully functional evaluation versions.

COMPUTER VIRUSES

An ever-growing menagerie of worms, trojan horses, viruses and other malicious codes are out to get your computer. Here's what to watch out for and how to minimize your data's vulnerability.

AnnaKournikova, ILoveYou, Christmas Tree, Melissa, Homepage, Bubble-Boy.... These seemingly harmless names usually show up in the subject lines of e-mail messages, tempting people to open them with promises of interesting stories, funny animations, cool web page links, or tantalizing graphics. In reality, though, these are actually bugs -- programs that can destroy software programs, allow hackers to access a network, or cause some other kind of electronic vandalism, and then move on to the next computer.
Melissa, AnnaKournikova, and a handful of others are already infamous enough so that most people know to avoid them, but thousands of worms, viruses, and other so-called malicious codes are out there, posing a risk to anyone who isn't prepared to deal with them (and even to those who are).
Computer viruses are getting smarter, more widespread, and increasingly difficult to detect, and dozens more are added to the menagerie each day. But don't panic: antivirus software is becoming more sophisticated, too.
Take sonar equipment out of the water and put it on your desk, though, and it isn't very useful at all -- until recently, that is. By exploring the possibilities of a scientific application known as magnetostriction, researchers and companies are taking some of the technology behind sonar and making it useful out of water. By the middle of next year, REALTORS® could be using this technology to speak with clients over the phone. The office of the near future may be full of the same sonar technology, incorporated into walls and furniture, changing the ways we communicate.

What Are Computer Viruses?
In a nutshell, computer viruses are small programs that attach themselves to computer applications and wreak havoc on a computer system. Some actively destroy software or entire computer systems to render them unusable, some can delete files, some open up a doorway to let hackers onto a network undetected, some can be used to initiate denial of service attacks (see Web Intelligence Summary #3 for more on DDoS attacks), some cause text or graphics to be displayed where they aren't wanted, some slow down a computer's communications and processing capabilities, some just sit there and don't do much of anything.
They can also cause significant economic damage: In May 2000 the I Love You virus, according to the International Center for Security Analysis, caused nearly $2.6 billion in damages within the first 72 hours of its initial release.
There are several different kinds of these malicious codes (usually referred to collectively as viruses, bugs, or malware). The basic types include:
Viruses are programs that spread when infected files are transferred from one computer to another. A virus program will associate itself with another program, so that when the program is started, the virus is released at the same time.
Worms often infect whole computer systems, and are often spread through e-mail attachments. When a person clicks on the attachment, the worm is launched, and then spreads itself by mass-mailing itself to the e-mail addresses listed on the infected computer. Other worms, however, can spread on their own, without human intervention.
Trojan horses are programs disguise themselves as something else. A user might open a file expecting to see a photograph or a spreadsheet, but turns out to be malicious code instead. True trojan horses are targeted to specific computer systems, and are not made to distribute themselves around. Like other bugs, Trojans can cause damage to files and allow hackers to access a system, but according to a recent report from Wired New, they can even be used to give a remote user complete control over a computer's functions in some cases.
Most of the malicious codes infecting systems today are actually hybrids or mongrels, combining different characteristics of viruses, worms, and/or trojan horses. The AnnaKournikova virus, for example, is both a worm and a trojan horse: users click on the e- mail attachment expecting to see a picture of the famous tennis star, unknowingly releasing the bug to do its work and e-mail itself to other computers. More recently, another trojan horse/worm began showing up in e-mail boxes in mid-May, disguising itself as an antivirus warning from Symantec, one of the top makers of antivirus software; readers who opened the message expecting to find out how to protect themselves from a new virus unwittingly exposed themselves to one instead.
As of December 2000 there were 55,000 known bugs, with 10 to 15 new ones created each day.

How Does It Work?
The key behind the Soundbug is a small piece of Terfenol-D, a mixture of iron and rare earth metals. Terfenol-D was first developed by the U.S. Naval Surface Warfare Center in the 1970s for use in underwater sonar systems. Newlands Scientific, a research firm spun off from England's Hull University, recently began exploring the possibilities of Terfenol-D, and came up with the Soundbug as its inaugural product. The Soundbug transmits sound to flat, smooth surfaces through the piece of Terfenol-D, which is encased in aluminum. A coil is wrapped around the aluminum case. When electricity is passed through the coil, the Terfenol expands, making the flat surface vibrate and broadcast sound. It works best when attached to dense materials.
The magnetostrictive technique allows sound to be spread evenly over the whole surface of an object, creating a more uniform distribution of sound than is possible with conventional loudspeakers. So in a restaurant, for example, instead of having loudspeakers installed in a few single locations, magnetostrictive devices could be placed in the ceiling tiles to spread background music evenly across the entire room.

Prospects & Potential Uses
Malicious codes have been around almost as long as desktop computers. The first viruses appeared in the late 1970s and early 1980s, spread via floppy disk. Some still travel on floppy or zip disks, while others move on their own through network connections, but more often than not, e-mail is the main means of transferring bugs from one computer to another. The number of viruses arriving through e-mail increased 300% in 2000.
In general, computers that run on popular Windows 3.1, 95, and 98 operating systems have been the most vulnerable to viruses. Bugs have been able to proliferate and spread using weaknesses in e-mail programs, word processing macros, and other common applications found on Windows-based computers worldwide. Other types of systems can also be exposed, however. In recent months, new viruses have appeared that focus on computers running the Apple and Linux operating systems. A few that even attack handheld computers and wireless devices have also started cropping up. Currently, Windows NT and UNIX systems seem to be the safest, since they include a host of security features that help keep viruses away.
Another recent development in viruses is the emergence of programs that can alter themselves slightly in order to avoid detection. All malicious codes have their own distinct signatures; antivirus programs work by detecting these unique signatures and reacting appropriately when one is found. Some of the new viruses, especially one called Hybris, have the ability to morph -- changing a bit of its own code so that antivirus programs won't recognize its signature. Each time Hybris jumps to another computer, it changes, making it extremely difficult to track. More and more viruses are displaying this trait.
In the effort to protect computers from viruses, major antivirus companies such as McAfee.com, Symantec, and Finjan Software are coming up with new tactics. Antivirus software works most effectively when a computer has up-to-date virus definitions to refer to. The companies rely on their subscribers to dial into the antivirus servers and update their software with the latest definition files on their own. Because too many computer owners don't update their software regularly and since so many new viruses are created daily, antivirus programs often are unable to work as well as they could. McAfee.com has started to work around this problem by distributing its antivirus definitions to subscribers automatically through peer-to- peer networking (see Web Intelligence Summary #13 for more on this topic); when a subscriber's computer is connected to the Internet, McAfee's new distribution technique allows the computer's antivirus software to update itself as often as once every minute.
However, even constantly updated antivirus software is not infallible. Antivirus programs can only keep computers from being infected by bugs whose signatures they recognize; variants and brand-new bugs can easily slip through. A few companies, including Finjan Software, have been researching a new kind of antivirus software that can block malicious codes even before they have been officially identified. Instead of detecting virus signatures, this new antivirus software watches for certain behaviors generally associated with viruses and prevents the bug from infecting the rest of the computer system.
Impacts on REALTORS® & the Real Estate Industry
Like anyone else who uses the Internet, REALTORS® and association executives have a vested interest in ensuring that their computer systems are protected as much as possible from the threat of viruses. Several real estate offices and REALTOR® associations were affected by the outbreak of the Melissa virus in 1999; countless others have experienced problems caused by other forms of malware since then.
Serious viruses can bring down an MLS server or company website, preventing prospects from searching for listings or accessing a broker's homepage. They can ruin expensive software or compromise sensitive customer and member information. They can also cause major damage to a company's reputation: imagine what might happen if a virus infected an agent's computer and then redistributed itself to everyone in the computer's e-mail address book, including those used in online farming campaigns.
The costs of replacing software and hardware, lost employee time, the loss of potential customers, and other damages can really add up: according to the International Computer Security Association, an average company (this includes all firms, not just real estate companies) spent an average of $120,000 in 2000 as a result of damages from computer malware.
In order to prevent problems and loss of business from virus attacks, real estate companies and associations should make sure that their computer systems are equipped with e-mail filters, antivirus software, and up-to-date antivirus definitions. It is also essential that agents, personal assistants, and other employees be educated about the dangers malicious codes can present, and how they can take steps to minimize the risks. Like lockboxes and practicing safety measures at open houses, effective computer security plans should be an integrated, carefully considered aspect of any company's safety policies.

Avoiding Computer Viruses
Ultimately, antivirus experts believe, the only way to truly prevent malware from infecting computers is through a global immunization system. Such a system would be able to detect new viruses anywhere on the Internet, create an antivirus to combat it, and then distribute it automatically to every computer connected to the Web.
This concept is a very long way from becoming reality, however. Until then, there are a number of ways you can minimize your computer's exposure to worms, viruses, trojan horses, and other electronic bugs:
Use antivirus software: Invest in antivirus software for your computer system. Packages are available for individual users and larger networks. Symantec and McAffee are among the best- known antivirus programs for individual or networked computers, and can usually be purchased for under $100 for single computers. Some computer security experts also recommend using antivirus software from more than one vendor for even further protection. The University of Magdeburg in Germany has an extensive antivirus testing website (in English) that reviews the effectiveness of different packages:http://www.av-test.org.
E-mail filters can also be an effective means of stopping viruses in their tracks. Filters can be set to examine any or all e-mail attachments, and then block or isolate any suspicious files trying to enter the system.
Once the antivirus software and e-mail filters are properly installed on your computer, make absolutely certain to keep the software and antivirus definitions updated. Most computers can be scheduled to run the updating process automatically; once or twice a week is usually sufficient for the average user.
Real estate companies and local associations might even consider outsourcing their security measures to ensure that software is properly installed and kept current. Another option recommended by security experts is to assign someone to be the "antivirus czar" in each team or department, someone who will be responsible for making sure the other employees keep their systems updated and knows what measure to take when a virus hits.
Avoid macros: A number of viruses can enter a computer system through macros, which are often used in Microsoft Word documents. The Macro Virus Protection option should be enabled in all Microsoft applications (in Word, open the Tools menu, then choose Options, then select Macro Virus Protection under the General tab). If an e-mail attachment comes with macros, it is usually best not to install them on your computer; the document should still be usable without them.
Don't allow Windows to hide file extensions: As mentioned above, the vast majority of malicious codes travel from computer to computer via e-mail. More often than not, they come in the form of a VBS file. VBS, which stands for visual basic script, is a programming language used in many computing applications, and is often the format-of-choice among those who write malicious codes. VBS files can sneak into a system by piggybacking on another file extension: The Anna Kournikova virus, for example, was sent out as a JPEG file, which most computers recognize as an image. In fact, it was actually AnnaKournikova.JPG.VBS -- the VBS was ignored because most Windows systems are usually set to display only the first extension they see.
VBS, VBX, and EXE are signals that the file is a program and possibly a virus. Making Windows show these extensions on any files you receive will go a long way towards averting potential e- disasters.
You can easily set Windows to show the entire file name, with all extensions, of an e-mail attachment by entering the Windows Explorer program. Select View, then Folder Options, and uncheck "Hide file extensions for known file types." (Check with your company's computer help desk first, since there are some system files that are hidden in order to keep them from being accidentally deleted.)
Create backups of important data: Make it part of your routine to create duplicates of any essential files on your computer and keep them on a separate disk. In case a virus does hit your system, these backup files will help ensure that your important information isn't permanently lost.
Be careful: Although it sounds pessimistic, one of the most important tips for avoiding malicious codes is to trust no one. In other words, keep an eye open for anything suspicious. If your friends and colleagues are suddenly sending you e-mails with unexplained attachments that they don't normally send, or if spam from unfamiliar companies appears in your inbox, resist the temptation to open them. Only download software programs from reputable websites; pirated versions of well-known software might be cheaper in the short run, but they can often include viruses. If you're unsure what a file is going to do before you open it, then don't click on it.
These tips won't prevent all viruses from infecting a computer, but by using antivirus programs and being wary, you'll be well-equipped to avoid most bugs and keep your data, pocketbook, and reputation intact.

NAR's Web Intelligence Summary

http://www.realtor.org/

Online Antivirus

Horoscopes

Currency Exchange Calculator