Computer Blog

What is a firewall?

This is a common question. In IT, a firewall is used to keep unauthorized users away from a computer or a network. A firewall can be hardware-based, that is a physical box with software, or software based, which runs on a normal computer. Here is a short firewall overview.

The success of the Internet created the need for firewalls. A computer which is connected to the Internet is very likely to get attacked. The Morris Worm, released in November 1988, was the first large scale attack on the Internet. It was not malicious but infected thousands of computers. The main reason was that most system administrators had not expected to be attacked and had not secured their systems. The problems caused by the very simple Morris Worm changed Internet security. One of the main solutions for preventing attacks became the firewall.

The early firewalls were mainly using basic packet filtering, making it possible to specify allowed traffic and rejecting or silently dropping all other traffic. Packet filtering is easy to implement but it does not work well in a dynamic environment like the Internet. Another early feature of many firewalls was NAT, Network Address Translation, hiding the internal structure of the network behind the firewall. NAT also makes it possible to use private IP addresses (RFC 1918) on a network. This makes it possible to hide a whole network, using private IP addresses, behind one single public IP address. This both preserves IP addresses and increases the security of the private network.

Nowadays, you have a lot of firewalls to choose from. The high-end solutions are very expensive, aimed at large organizations which need to protect themselves against a number of threats. For a home network connected to the Internet with a broadband connection, a combined wireless hub/router/firewall is a cheap way of protecting your computers at home. Strictly speaking, such devices are no real firewalls but they can protect you against most threats. You should still run anti-virus software on your computers, even if they are protected by a firewall.

Windows operating system has firewall software as well. The software has been included since Windows XP. The early versions were very basic and often created problems. But the Windows Firewall software has been improved and provides a reasonable level of security. But it is highly recommended that you pay for anti-virus software which also protects your computer from external threats. They are much better than Windows Firewall software. Note that most of them will disable the Windows Firewall software.

When it comes to security, it is generally best to go for the popular solutions. Most of the security flaws have been detected and fixed. Firewalls that are not used much may not have as many known security flaws as the popular firewalls but that does not mean that they are better or more secure. On the contrary, firewalls that are not widely used could have some serious security holes but they have not been detected because very few uses the product. You don’t want to be the first one to detect a security flaw in your firewall.

The modern firewalls are very efficient, most IT security issues are generally created by insiders. Internal threats are nowadays much more serious than threats from the outside. Firewalls are used to protect the organization from threats from the outside world, not against attacks from the inside. Here you can learn how you can protect yourself against attacks from the inside. Today, the biggest threat from the outside for many organizations are distributed denial-of-service attacks. This is not really a security problem but it makes difficult for clients to reach the computers of the organization. Few firewalls are designed to handle such attacks. Fortunately, large scale distributed denial-of-service attacks are rare and only a problem for some well-known organizations.“

Another Type Of E-Mail Scam

Have you ever received an email from a friend (or friend of a friend) saying they heard about a recent scam? You must have!  I think it has happened to almost all of us at some point. Think about it…

You open your email, see a message from your friend, click it, and get bombarded with a message that they discovered the most recent email scam and want to share it with you.  By now, this has got to seem familiar.  The only twist is that the “discovery” email did not come from a trusted source, but from a random name you have never heard of.Now what?

Hit delete!  There is never a reason to open an email claiming to have heard about a scam from an untrusted source and there is definitely NEVER a reason to click on a link in an email from an untrusted source. Links and downloads from untrusted senders is the prime vehicle for malware, spyware, or a virus to be sent.

Always be on the lookout and avoid any emails that seem suspicious or have random links.  One click can put your entire computer system and all of your personal information in jeopardy. Tht’s why we always prefer disposable email providers

Viber – Free IPhone VoIP Application

Viber – the Free iPhone VoIP app without the hassle of registration or sign up. You install the app, run and authenticate your phone with a pin code (authenticated via SMS verification) and start making FREE calls, simple as that. More exciting than this it that it doesn’t require the app to be running all the time, even in the background. Sounds too good to be true? Brace yourself for the exciting ride! This is something Skype has been lacking all along. You’ll have to have Skype running and signed in to be able to make or receive calls.

With Viber, a logo appears next to your contacts so you know exactly who to call in Viber. I personally don’t think it could be any simpler than this. The call quality seems to be very good, a lot of people are claiming it to be better than Skype. But I guess, that’ll depend on your data connection (WiFi/3G) and speed.

But be careful before you get too excited and start using it aggressively over 3G because it is a VoIP app and it uses your data. So always keep an eye on your usage. Check out the video below and let us know your experience with Vibe

When Smartphones Killed Boredom

Smartphones are pretty damn useful and they’re also very distracting. It doesn’t take very long to scroll through a rapidly updating real-time timeline of what the world is doing right now. Same with checking where your friends are currently and who all are starting to fall into the trap of holy matrimony. Smartphones can let you do all that and more.

The part that bothers me the most if that we’ve traded the me-myself time with hours and hours of sending and receiving SMS . Getting bored meant sitting around or just waiting with nothing to do. It freed up the mind so it could cultivate ideas. I get some of the best ideas when I’m practically sitting like a duck for hours, doing nothing. It sounds annoying but it’s something I could really use.

Not anymore though! Now if there’s a minute to spare, my hands automatically search for the iPhone in my pockets or my table, pick it up and, almost as a reflex, open up Twitter, Facebook, Instagram and what not. With WiFi and 3G on the go, it makes things much easier for me. It’s kind of amazing that one can document almost every moment of their life, while ignoring almost anyone who might be standing right next to you.

It’s interesting and kind of worrying at the same time. The price you pay for technology.