Firewall is a software or hardware device that protects your computer from being attacked over the internet by hackers, viruses, and worms. This may occur either at a large corporate network, or simply at a small home network; both have the same security issues.
Having a firewall in each company’s internet connection allows the business to setup online rules for the users. For example, with the firewall the company can control the access to certain websites, giving it the control of how employees use the network. These are the different ways of how a firewall controls the online activities:
Packet filtering: small amount of data is analyzed and distributed according to the filter’s standards. .
Proxy service: online Information is saved by the firewall and then sent to the requesting system.
Stateful inspection: matches specific details of a data packet to a database of reliable information.
Firewalls allow you to either add or remove filters based on certain circumstances such as:
IP addresses: If a certain IP address, not belonging to the company’s network is accessing too many files from the server, this IP can get blocked by the firewall.
Domain names: with the firewall, a company is able to block or allow access to certain domains.
Specific words and phrases: The firewall will scan each packet of information to match the filter content. You may select any word or sentence to be blocked.
Protect your home computer at home by turning on a firewall, or if you have more than one, use a hardware firewall (such as a router) to protect your network. If you use a “public” computer, you should follow the network administrator’s policy.
Even though some firewalls offer virus protection, it is recommended to install anti-virus software on each computer. Depending on the layers of security you use, you will determine how many threats can be blocked by your firewall, and prevent any outside user to login into your private network.
In cases when you need to allow remote access from others to your network, you may create a DMZ (Demilitarized Zone). This is an option provided by most of the software firewalls; they will designate a directory on the gateway computer as a DMZ.