In computing, a firewall is a network security system that monitors and controls incoming and outgoing network traffic based on predetermined security rules. A firewall typically establishes a barrier between a trusted network and an untrusted network, such as the Internet.
Firewalls are categorized as a network-based or a host-based system. Network-based firewalls can be positioned anywhere within a LAN or WAN. They are either a software appliance running on general-purpose hardware, a hardware appliance running on special-purpose hardware, or a virtual appliance running on a virtual host controlled by a hypervisor.

Use UTM Firewall

Unified threat management, commonly abbreviated as UTM, is an information security term that refers to a single security solution, and usually a single security appliance, that provides multiple security functions at a single point on the network. A UTM appliance will usually include functions such as: antivirus, anti-spyware, anti-spam, network firewall, intrusion detection and prevention, content filtering and leak prevention. Some units also provide services such as remote routing, network address translation (NAT), and virtual private network (VPN) support. The allure of the solution is based on simplicity, so organizations that may have had individual vendors or appliances for each separate security task can now have them all under one vendor umbrella, supported by one IT team or segment, and run through one console.