A Firewall is a network security appliance or device that accepts or rejects data traffic to or from the internet (WAN) from a private network (LAN) based on access rules. Firewalls help secure an internal network from an untrusted network like the internet. There are hardware based firewalls and software based. Information technology best practices says the best combination is to have both. Windows operating systems have a basic built in software firewall called “Windows Firewall”, but by no means is it better than a comprehensive security suites like Sonicwall Firewall Services, Kaspersky, Symantec and Zone Alarm to name a few.
Hardware based firewalls usually sit on the perimeter of your network, though sometimes used to separate departments in an office. In many cases a hardware firewall solution is ideal for businesses that want an umbrella that can protect multiple systems at the same time. Low end firewalls are now found in combined devices with a router and a switch built in for your home, but they have their limitations. Hardware Firewalls usually have some router functions built in, along with other features to help manage your network like DHCP services.