Personal firewall

From ArticleWorld

A personal firewall represents software placed on an end-user's computer that functions like a conventional firewall. The main difference between a personal firewall and a conventional one is the lack of specific hardware. The personal firewall is simply a piece of software, and it is usually designed to protect no more than one computer. Personal firewalls usually tend to assume that an user is present at the computer most of the time, and therefore it is common practice for them to prompt the user for an answer if a rule is not defined, but suspicious behavior is noticed.


  • Prevent some applications from accessing the network.
  • Restrict the access to some services
  • In some cases, some intrusion detection features are present, allowing such measures like terminating an application on which an intrusion suspicion is pending.

Personal firewalls tend to be easier to use and configure than most of their conventional counterparts, since they are targeted at users with less computer experience.


Although many specialists agree that it is a good idea for a home user to install a personal firewall, some criticism does exist, especially targeted against the fact that a personal firewall is not enough to secure a computer.

The main things pointed out by critics are:

  • It is common practice for users to install a firewall, even though they don't actually require such advanced functions. For many computers, simply shutting down any unneeded programs that use the network is enough. For example, a computer used only for browsing the web, especially with a more secure browser like Opera, hardly needs any form of firewall.
  • Firewalls are pieces of software, so they are all vulnerable to bugs. If an attack can be designed to target the firewall itself, it can affect the host system as well. This is rarely the case of attacks which try to obtain access to the host, but DoS attacks against a firewall are known to have been attempted. Firewalls are also susceptible to be "sabotaged" by malware software already present on the host when the firewall is installed.
  • Personal firewalls often grow more paranoid than they should, alerting the user about an attack even though there's nothing wrong. Some actually see this as nothing but a marketing strategy of commercial personal firewalls distributors who try to make the user believe it is much unsafer to work without a firewall than it actually is.