It's about Firewall

Tuesday 27 July 2010

Rely solely on a software firewall is not enough. Collaboration in a compact with other security software is essential in making the PC an ideal defense in warding off a variety of malware and hackers.

Do you dare to fly a plane without a pilot's license? The answer is unlikely. Viewing the contents of the cockpit alone may directly reduce your guts. Although the use of soft ware firewall is not less complex as flying a plane, is generally not afraid amateur users to install it because the active firewall software automatically. Users who feel safe (because it has a firewall-protected) is finally with confidence direct "flight" to the virtual world. Did he really have a safe?

PC firewall as protection is still debated on the Internet. One of the Newsgroups with security specialization, even suggested the extreme to rule out some kind of firewall from a PC because of less effective to protect your PC, even spend the PC resources. The call above is true. What really is needed is a PC user protection system in a compact and complete. Firewalls are only one of its components. Then how firewalls work, manipulated, and integrated into a total security concept.

The workings of the firewall
If the company used to use a hardware-based firewall, personal users use a software firewall such as ZoneAlarm or the Windows default firewall. Today, WLAN router, the Netgear RangeMax NISO also has an internal firewall. All solutions above checks incoming and outgoing data packets, and filter it if necessary. The information is important for a firewall between the other PCs IP addresses (source and destination) and port (protocol) used to send or receive data packets.

Desktop firewall has a filter application (Application Control) to allow or disallow an application to access the Internet.

Many firewalls offer extra facilities, such as "Learn Mode" that adjusts the filter rules with user behavior and the "Content Filter" that block ActiveX components, JavaScript, and so forth. Firewalls of this type are sold as "webshield" or "Web Application Firewall." Who also began offering the "Stealth Mode" which block all unused ports request (Deny Mode).

One of the facilities are usually present at almost all hardware firewalls are "stateful Packet Inspection (SPI)." These facilities improve the standard filter rules. If you, for example, run the browser, some occur in parallel connection, so some of the services often send (receive) packet active simultaneously. In examining the data packet, the SPI refers to the connection status. Whether the data packet originated from an existing connection? Is required by the browser to receive the reply packet? Based on these questions and many others, the firewall decides whether the packet forwarded or blocked.

Any filtering system that used a firewall, the same goal, namely to block suspicious packets coming from the Internet (for protection against attacks from outside). If the malware could escape onto the hard disk, a firewall can no longer just went (some manufacturers firewaal still has its own arguments against this fact). Why?

Ideally, packet filtering can be relied upon to protect your PC. In fact, not so.
Prior to hackers trying to infiltrate a firewall, he should know, vulnerabilities that exist on the PC, such as a browser bug, or a file Windows service (printer) sharing the wrong configured. What also might happen is the inclusion of a trojan (when opening e-mail attachment) or malicious code (when accessing the website). All these attacks can pass through the firewall filters for e-mail client or browser are generally not blocked by the user. For example, MS Outlook can directly send or receive e-mail containing a trojan because of firewalls itself that gives him access.

As part of a comprehensive security package, desktop firewall must always be improving its ability to identify malicious code by working with other security modules, such as antivirus for better overall protection. A good firewall automatically evaluate the types of data traffic, open or block the connection without popup window always displays a disturbing, depending on whether the data packet is good or evil. Unlike the default Windows firewall, a good desktop firewall also checks the data traffic (incoming and outgoing) in standard configuration. He also provides Intrusion Prevention functionality that can anticipate and block new attacks, even when the system is not security holes are patched.


Dangerous from the desktop firewalls is that we've felt safe in the protection. Whereas some firewall protection mechanism still has weaknesses. Usually, the browser acces allowed the firewall to the Internet via HTTP connection. Conversely, an unknown program may not contact a service is also not yet known on the Internet. However, if a smart trojan neatly wrapped in HTTP communications and transfer them via a web browser that is connected to the Internet, firewalls automatically allow it. When we realize the limitations of a firewall and combining it with other security software with, for example, Antivirus, and treat system (updates, etc.) on a regular basis, the PC must be properly protected