A Firewall is basically a logical layer between the network connection and your computer which filters out the data entering and leaving your computer.

When you are using the internet, you are using a two-way traffic. Even while surfing you are both downloading and uploading data at the same time. You are never sure over the internet of the fact that whether the content you are viewing is perfectly safe or being used to open a port on your computer through which a third party might steal out  your personal or crucial information. The internet is filled with hackers who are looking for opportunities like this to step into a connected computer and may leave everything intact or may harm your data or compromise some crucial information like credit card numbers and passwords. This is the point where a Firewall comes into play. It is one of the most popular measures to reduce the probability of being compromised by a wandering hacker or a website which might leak your private information.

“Technically, a firewall can be a router programmed to filter some specific type of data or a PC combination of hardware and software configured specially for monitoring incoming and outgoing traffic from the host computer.”

“Theoretically, all the data travelling over the network will pass through the firewall, so it will be monitored according to the firewall’s rules, reducing chances of unauthorized access.”

Firewalls are not gateways, but they often do work in association with gateways. Both firewalls and gateways tend to sit between networks. The gateway’s job is to translate packets as they move between different network environments; the firewall’s job is to filter the packets. Generally a gateway can be taken as the gate or path which joins together two networks that use different base protocols. Then, a firewall can be treated as a guard standing in that gate who permits or denies data packets.

There are several ways of threats through which information regarding your network can be compromised if preventive measures are not made. Some of these are; Remote Login, Application Backdoors, SMTP session hijacking, operating system bugs, Denial of Service attacks, Email bombs, Macros, Spam, Redirect bombs.

It is not necessary that a firewall detects and eliminates all of the above mentioned threats, but there is a highly reduced chance of security being compromised through these threats when you have a decent firewall at the head of your network. A firewall is usually configured to allow only specific data to be directed through the network. Although it’s always a good plan to setup anti-viruses on all your workstations, firewalls are specialized for network traffic while anti-viruses are particular for local traffic (information flowing within a single computer). Firewall can also be set on workstation which just protect that single workstation.

Watch that how a firewall works in the video below:

A while ago when I was searching for a cooling solution for my laptop as it was running hot due to its high specifications and thus delivering the high performance. I got the cooling solution that I never saw before. It was a cooling fan that is used to extract the hot air out from the notebook. Unlike the traditional cooling pads it fits on the outer side of the air vent of a notebook. It is compatible with all the major notebook brands but keep in mind that it simply fits on notebooks which have vertical rectangular opening bars on the air vent of the notebook and it may not fit properly on notebooks which have diagonal rectangular bars or some other design air vent. I am using it with my Thinkpad notebook W500 as it is equipped with ATI Radeon Mobility graphics with 512MB of memory plus system memory sharing which totals upto 2GB of graphics memory which gives extra ordinary performance and also a large amount of heat which is obvious with such performance, so in order to keep my notebook cool and making it reliable I decided to look for a different and more effective cooling system and this evercool air extracting fan really impressed me due to its unique and traditional style of cooling i.e. extracting the hot air out of the system. While the other cooling pads do not cool notebooks in this way, those just cool the bottom surface of the notebook and not much the inner components.

Most of the notebooks have their CPU heat sink fans enough away from the air vents due to which they can’t push all the heat out of the system easily. So an air extracting fan be much effective as compared to the cooling pads. Despite of the way of cooling the speed of air flow is also sufficiently increased in air extracting fans. The average fan speed range of cooling pads is 600-1800 RPMs while that of air extracting fans is 3000-3800 RPMs.

The manufacturer of this fan says that it is the world’s first Patented NB Air Extracting Fan. Hope this topic is helpful to you and it increased your knowledge. Please write the comments if you want to say anything.