Firewall is software that allows to protect our computers and servers against attacks that nowadays occur every few minutes. The firewall allows you to determine which elements of the network are trustworthy and properly filter access to the local network. What is a firewalls?
Most often a firewall is a dedicated program that the user installs in the operating system. It is also a service that you can activate with an Internet operator for a small fee, or an element of network infrastructure – a separate computer, network module or router element.
A firewall is a first-line defense tool for any good network protection system. It prevents data intrusion and theft, which is quite important at a time when each of us uses online stores and online banking. After all, none of us wants a hacker to intercept our financial information!
A firewall, as IT definitions say, blocks unauthorized data transmissions from inside or into our private computer network. A firewall is a way to prevent data being stolen by hackers and intruders to place malicious data on your computer. The firewall also blocks unwanted installations of malware via the Internet. Thanks to this, figuratively speaking, a hacker encounters this “wall of fire” if he is trying to access data on our computer.
A pingflood attack involves “bombarding” a computer with ICMP packets of larger than allowed size (ie greater than 65,536 B). The ping program is used to send them. As a result, the compromised computer (or server) may be heavily loaded or may even restart automatically.
The effects of a land attack can be the same as those described above for pingflood. However, the course is different. The attacker sends a forged packet in which the IP address of the recipient computer is the same as the sender’s IP number. The victim machine tries to respond to the information received, but since the sender’s address was forged, it connects to itself.
Many ICMP protocol packets are routed to the network, whose return address has been replaced with a broadcast address (so-called broadcast; in some literature it is called a broadcast address). As a result, all computers in the network begin to respond to the information received. The attack affects the amount of unnecessary traffic generated.
This type of attack often announces another one (for example, attempting to infect your computer with a Trojan horse or worm). A cracker (or script written by a cracker) scans your computer to detect free ports through which it will be possible to “implant” malicious code, or to gather some information about how the network is used (e.g. whether the attacker uses peer to peer programs or email).
Given the scale of threats we are exposed to on the network, implementing a firewall is necessary for the efficient and, above all, secure operation of the company. It is a security that effectively protects against port scans and attempts to infect your computer, the desire to eavesdrop and send messages aimed at intercepting and stealing data.
Remember that the firewall does not protect against viruses! It provides security against another, equally dangerous type of attack – direct hacking into the computer.