Computer network security is becoming more and more important. Windows 7 as Microsoft's next-generation operating system, a new interface, more user-friendly features make operation easier, especially in terms of security than the previous system is more stable and reliable. But win7 really safe? The answer is no, then how to resist viruses Win7 system.
often hear "more professional" IT staff that "the user installed antivirus software even , but that the concept of anti-virus did not, thinking that it would not be poisoning you? "
order not to poisoning, more importantly, to better understand the operating principles of preservation of the virus, and anti-virus software Road. Here, I hope that for the computer users of general enterprises, we can provide some "anti-virus concepts" that are sufficient. Maybe not "guarantee" anything, but at least you can have a synopsis of what the computer to recognize it happen!
delicate fragile boot program
computer had to be switched from the open The power is always loaded until the operating system is loaded. This is commonly known as the "boot program." Since most viruses will try to allow themselves to be part of the "boot procedure" (and to a parasitic infection), so you have to know the entire program What are the steps:
1. Power On, if the hardware is carried out as usual the next step
2.BiOS (basic input /output system) to perform routine boot check, then the default storage means take over the boot program
3. in accordance with a recognized standard, pre means provided in the boot (typically a hard disk unit) to begin the boot software programs sequentially loaded core operating system, drivers ......
4. loading the operating system kernel, but also according to the setting, loaded using various resident program (antivirus software, IM software ......) specified by each of the above
a boot program, a step from this to the next step, will leave a "hook point." For example, the BiOS system on the motherboard should execute the boot program of the storage medium. It will execute the boot command from a fixed location. Where is this fixed location? We don't need to know it, but this location is definitely a public specification.
so, write the operating system knows the location of the boot storage media, write disk maintenance programs people know, people know to write utilities, and people who write viruses ...... certainly know, so there The so-called "boot-type virus."
However, this modern "open type virus" is very rare, mainly because of the boot, load the operating system are quite large and complex, this virus can be difficult in such a complex situation the boot working normally. Most of the current viruses are mostly destroyed in the operating system.
possibility can not boot there ......
whether it is Windows, MacOS, Linux or BSD, start loading the operating system is constituted by sophisticated sequential steps, followed by a link ring. The operating system usually has to set the operating mode of the processor, load the system core, driver and drawing interface, then load the resident program, and finally hand over the usage rights to the user. If this series of "exquisite" but also "fragile" process has a little mistake, the system can not load, the user will say "ah, this computer is hung up /crashed /can not open /died... many say, to name a few:
driver is out of the question
core program out of the storage disk problem
OS kernel of a problem
resident program users
a problem as long as there is a small link error, you can make the operating system can not properly load ── Fortunately, this situation does not happen often.
this So far, the above concepts seem to be very simple?