Types of Computer Security - Safety Concerns on Internet and Networks
Internet Security, among different types of computer security, covers malware and hacking techniques. The Internet is an open zone where anyone can create a website that may place malware on your computer or server. This is also the space that gives shelter to people who are on the prowl to reach your computer or servers to access your data for misuse.
You can divide the Internet into unknown and trusted sites. Trusted sites are simply the ones that you can trust, with a good example being your own office website. Obviously, you won't knowingly place any code on your own website to compromise the computer security of people visiting it. Another way to divide the Internet is into secure and non-secure zones. The secure zones are normally represented by a lock symbol in the address bar of your computer. An example of such sites can be your Internet banking site that employs high level encryption to secure their database as well as your computer.
While you already know about malware, there are two more common techniques used by hackers to access your data: port knocking and packet sniffing.
There are several ports on your computer that allow different applications to transfer data to and from your computer. A good application would instantly close the port as soon as it sends or receives information. However, there are some applications that delay or forget to close these ports. Sometimes it is the OS to blame. Port knocking, or port scanning, is the technique where hackers keep on trying to access the different ports on your computer or server. Once they find an open port, they can easily reach your data and use it the way they want.
You might know that to transmit data over Internet, it is divided into several chunks (called packets) of equal size. Each packet contains the sequence number of the packet preceded by the IP address of the computer or website (server) to where it is send. They also contain the IP address of source computers/network components such as servers (websites). These packets are mostly encrypted before leaving for the destination. Packet sniffing is another effective technique that helps hackers gain control over the source as well as destination computers. This is more dangerous than port knocking as it affects the entire network system. The technique involves observing the encryption and transmission patterns from a computer/server to the ISP's server. Other hackers can also sniff data transmission from certain websites. Once they crack the encryption, or if the ISP or website does not support high level encryption, the data is easily accessed by the hacker. Once accessed, even a data chunk can give further clues to the hacker for gaining total control over a computer, network, and even a website.
This is why most browsers use high level SSL encryption to keep your data safe. Still, no software is perfect and may give out details if there is any kind of security lapse on part of end-user, ISP, or the website developers.