If you have more than three computers in your home or business that use the same Internet connection, the hardware firewall is something you should consider. A hardware firewall is a device that is located between the Internet and the network, protecting every computer from inside against external intruders.
A (or Personal Firewall) software version against a hardware firewall was designed to protect all computers in place of a single computer. In general, it is more efficient and cost-effective to purchase a hardware firewall (as opposed to multiple software firewalls) if you need to protect three or more computers.
A hardware firewall is a special tool designed to prevent external intruders from bypassing the network (where they can easily access their computers and servers) . Firewalls can be configured to prevent access to certain types of applications that are dangerous to (such as P2P file sharing programs) blocking the communication ports used by the application. The firewall also protects against hidden spyware infections as it helps to stop outbound data packets that the infected computer sends to computer criminals.
Firewall is the first line of defense to protect computers against unwanted "visitors", such as hackers, worms, and remote control applications, against hidden spyware. Without protecting the firewall, the network is an "open door" for the Internet and anyone can easily access and exit from any of the (or whatever) . Even if there are no important files that protect you, hackers and intruder intruders will easily kill all your computers, take control of the network, or damage your hardware. A smaller investment in a firewall can not be compared to the cost of replacing or repairing computer equipment, which is the consequence of an intruder's visit.
Hardware firewalls use different techniques to protect network intruders and other Internet threats. All firewall rules can be configured to be applicable to outbound or incoming traffic, giving you a lot of flexibility and control over the firewall. Hardware firewalls can be simple or very complex, depending on the size of the network they are designed to defend. High-quality corporate firewalls must be installed by an authenticated technician, but most home and small-scale firewalls can be set up by any person who is generally familiar with networking and good technical capabilities.
Most hardware firewalls use some sort of packet filtering, somewhat similar to a "checklist". Some data packs are enabled and others can be blocked. If packages within or within the network meet the "blocked" conditions, they will not be allowed.
Another technique, often used with hardware firewalls, is also known as Stateful Packet Inspection, also known as SPI. With SPI, the hardware firewall analyzes additional features of the data packet to determine what to do with it. It looks at where the package comes from if it was sent as a response to a user request, if it's just "released" and so on. Combined with packet filtering, SPI actually creates a firewall device "intelligent" as it can decide whether or not to block data packets based on logic analysis.
Depending on network types, hardware firewalls can cost anywhere near $ 100 to a home firewall device for up to several thousand dollars for an enterprise-class device. Easy (easy to install and configure) offers hardware firewalls for home use by D-Link, Lynksys and NetGear. SonicWall and HotBrick are very popular firewalls for small and medium businesses.