The internet is a powerful tool for every business. It also introduces a threat to networks, computers and its users.  The firewall is the network appliance that protects an internal network from the outside world.  It monitors the data on the network allowing or blocking traffic based on set rules.  The firewall also allows a network to split it into secure parts, record where users visit and allow remote access.

firewall - hardware firewall - windows

 Firewall Software and Firewall Appliances

  • Software firewalls, built-in to operating systems like Windows or Mac OSX, are basic and can only block a few attacks in a way suitable for home-use.
  • Software server firewalls are applications that can be installed on servers with other network applications.
  • Hardware firewalls are stand-alone devices whose only job is to act as a firewall.

Functions of a Firewall

  • Block or allow incoming or outgoing network traffic
  • Internet content filtering
  • Allow internal resources to be available remotely
  • Configure a VPN (Virtual Private Network)
  • Generate reports on traffic
  • Create VLANs (Virtual Local Area Networks)

What firewalls can’t do!

Firewalls cannot protect against internally introduced attacks that come from infected USB Flash drives or from outside machines brought in and connected to a network. Be careful what is allowed to be brought in!

Wireless Networks and Firewalls

firewall - wap

Using the firewall, a network can be split into public and private parts or Virtual Local Area Networks (VLANs).  The public WIFI allows access to the internet and possibly some internal information. The private, secured WIFI allows access to the entire network.  For example, “Public-WIFI” or “Private-WIFI” seen at airports or hotels.

A VLAN-capable, business-class firewall or wireless device is required.