One of my friend has got two computers and I have connected one through the other. So, on the main computer, which is connected to the internet, I have installed anti virus. Do I need to install the AV on the second one as well? The antivirus on the main computer will not stop any viruses in this way?
Can you explain how you have connected the computers together? I have used a switch (hub) or a direct crossover cable? Generally speaking, it would be a good idea to install AV on the second computer as well. Or you could install an AV server on the first machine, which would be able to protect the second computer as well. However, AV server software is quite expensive. You might want to check out Avast Antivirus Server Edition You should install a firewall on the computer directly connected to the internet. You do not need a firewall on the second machine (assuming it is connected directly to the first computer and not the internet)
Lets call main computer - A and second one -B So, A has two PCI network cards. One I have connected to the modem and second one is used for the B. I have used Cat5e to connect the comp A with B. I have installed AV on A. I thought that all the data is coming throught the A, so AV must be checking it. I know I can install Avast on the B as well but it will affect the speed and why do I install the AV on both the computers if A is doing that work for me. Have you got my point?
Take this example: You are downloading a ZIP archive onto computer B. An antivirus program won't scan that archive until you open it. So that ZIP file will go straight past the Antivirus program on Computer A. When you open it on Computer B, there is no antivirus program to detect the presence of a virus.
