Trojan horses and viruses are both artificial programs and computer viruses. Why did you mention the Trojan horse alone? As we all know, the role of computer virus in the past was actually to destroy and destroy the data in the computer. Apart from sabotage, other things are nothing more than deterrence and extortion by some virus makers in order to achieve certain goals or show off their technology. Unlike Trojan horses, Trojan horses are used to spy on others naked and steal their passwords and data, such as stealing administrator passwords-subnet passwords to destroy them. Or for fun, steal internet passwords for other purposes, such as game accounts, stock accounts, and even online banking accounts. To achieve the purpose of peeping into the privacy of others and obtaining economic benefits. Therefore, the role of Trojan horse is more useful than the early computer virus, which can directly achieve the purpose of users! Many program developers with ulterior motives write a large number of intrusion programs for the purpose of stealing and monitoring other people's computers, which is also the reason why a large number of Trojans are flooding the Internet at present. In view of these great dangers of Trojans and their different properties from early viruses, Trojans belong to a category of viruses, but they should be separated from virus types separately. They are independently called "Trojan horse" programs.

Generally speaking, if an antivirus software program can kill a Trojan horse with its Trojan killing program, then its own ordinary antivirus program can certainly kill this Trojan horse, because designing a Trojan killing tool specially for Trojans today can improve the product grade of this antivirus software and be of great benefit to its reputation. In fact, common antivirus software contains the function of killing Trojans. If people say that an anti-virus software does not have a program to kill Trojans, then the anti-virus software manufacturer seems a little guilty, although its common anti-virus software certainly has the function of killing Trojans.

One more thing, separating the Trojan horse killing program can improve the killing efficiency. At present, many trojan killing programs in antivirus software only kill trojans, without checking the virus codes in common virus libraries. That is to say, when users run trojan killing programs, the programs only call the data in the trojan code library, which greatly improves the killing speed of trojans. We know that the killing speed of common viruses is relatively slow. Because there are too many viruses now. Every file has to be tested by thousands of Trojan horse codes, plus nearly 65438+ million known virus codes. Isn't that slow? Do you improve efficiency and speed by omitting common virus code tests? That is to say, many anti-virus software's own Trojan killing programs only kill Trojans, and generally do not kill viruses, while their own common virus killing programs kill both viruses and Trojans!

All programs that can cause computer failure and destroy computer data are collectively called computer viruses. So in this sense, a worm is also a virus! As a computer program that is seriously harmful to the Internet, network worm virus's destructive power and infectivity cannot be ignored. Different from traditional viruses, worms take computers as carriers and networks as targets! In this paper, worms are divided into enterprise networks and individual users, and the characteristics of worms and some preventive measures are discussed from enterprise users and individual users respectively!

Similarities and differences between worm virus and general virus

Worm is also a virus, so it has the same characteristics as virus. An ordinary virus is parasitic in need. It can write its own instruction code into other programs by executing its own instructions, and the infected file is called "host". For example, the format of executable files under windows is portable executable files. When the pe file needs to be infected, a new segment is established in the host program and virus code is written into the new segment. The modified program entry point, etc. In this way, when executing the host program, the virus program can be executed first, and after the virus program runs, the control is given to the original program instructions of the host. It can be seen that viruses mainly infect files, and of course there are also linked viruses like DIRII and boot zone. Boot zone virus He is the boot zone of the infected disk. If a floppy disk is infected, it will also infect other machines after being used on other machines, so the mode of transmission is also a floppy disk.

Worms generally do not use pe format to insert files, but copy themselves and spread in the Internet environment. The infectivity of the virus is mainly aimed at the file system in the computer, and the infection target of the worm virus is all computers in the Internet. Shared folders, e-mail, malicious web pages in the network and a large number of servers with loopholes have become good ways for worms to spread. The development of the network also enables worms to spread around the world in a few hours! Moreover, the active aggression and sudden explosive force of worms will make people feel helpless!