For those of you who are used to connect to the internet, may have often heard the term firewall. Do you know what is Firewall means?
A firewall is a system or device which allows network traffic that is considered safe to go through and prevent network traffic that is not safe. In general, a firewall is implemented in a dedicated machine, which runs on the gate (gateway) between local networks , etc. Beside network, it is also used to control access to anyone who has access to a private network from outside parties.
Firewalls are divided into two types, namely:
1. Personal Firewall: Personal Firewall designed to protect a computer connected to the network from unwanted access. This type of firewall lately turned into a collection of programs that aim to secure the computer in total, with the addition of several additional security features - such a protection device against viruses, anti-spyware, anti-spam, and more. Today there are some other firewall product comes with interference detection function network security (Intrusion Detection System), for example: Microsoft Windows Firewall (which has been integrated into the operating system Windows XP Service Pack 2, Windows Vista and Windows Server 2003 Service Pack 1), Symantec Norton Personal Firewall, and others. Personal Firewall is generally only has two main features, namely Packet Filter Firewall and Stateful Firewall.
2. Network Firewall: Network firewall designed to protect the entire network from various attacks. Generally found in two forms, namely a dedicated device or as an installed software in a server. Examples of this firewall is the Microsoft Internet Security and Acceleration Server (ISA Server), Cisco PIX, IPTables in the operating system GNU / Linux, and sunscreen of Sun Microsystems, Inc.. that create a package in the Solaris operating system. Network firewalls generally have several key features, which is owned by other than personal firewall (packet filter firewall and stateful firewall), Circuit Level Gateway, Application Level Gateway, and also NAT Firewall. Network firewalls are generally transparent (not visible) from the users and uses routing technology to determine which package is allowed, and where the package will be rejected
