Layered security is a computer security philosophy that emphasizes using more than one security program for a computer or network, because it may be impossible for a single program to stop all attackers. Different programs from the same security brand do not count as separate layers; a new layer must be a security program from a separate brand. Aside from minimizing the errors in each security system, layered security also tries to deter attackers, because many hackers will become frustrated if they need to penetrate many security layers. Along with multiple layers, the computer or network should have a strong password, because a weak password can make all the layers useless.
When someone uses layered security, he is using two or more security programs simultaneously to protect a computer or network. The main reason for using two or more security programs is that one program may not be able to stop all attackers. By using several different programs at once, each one compensates for errors or gaps in the other programs by adding a new layer of security.
Most security program providers offer several different products, such as a firewall, an email spam blocker and an antivirus program, but these do not count as separate layers. Each layer must come from a different brand's security system if it is to be a viable layer. This is because, even though each program within the one brand has a separate function, each program in the suite is assumed to have similar errors or problems as all other programs in the suite.
Aside from minimizing the errors in each security system by adding layers, layered security also attempts to deter attackers with frustration. While some attackers like a complex challenge, most want to get into a system, cause damage and get out. With layered security, attackers may have to go through 100 security systems before they reach the actual system. Most attackers will give up before they breach the last layer, especially if they do not know how many layers are in the computer or network’s security.
While layered security is often effective, it has one potential weak spot: a weak password. If the user has a weak password that can be easily cracked, then the attacker can bypass all the security systems without much trouble. Regardless of how many security layers are used, the user should still make a strong password that cannot be easily guessed or figured out.