Network security are rules, which are established by the network administrator for prevention and control of unauthorized access, abuses and adjust. Network security includes an access to datas, which control a network administrator. Users can choose their own ID and password, which allows them an acces to information and programs and not to anybody else.
Network security includes a set of networks; for example: public and private which are daily use worldwide.
Basically network security provides network as well as the protection and supervision of operations carried in them. Everyone who wants to connect to this network needs to know the right password.
Antivirus software
What is it?
it is a computer software used to prevent malicious software.
Principles and functions: searches and checks data on the basis of the virus database. This virus database has been updated to users for download, which is usually done automatically.
Firewall
Firewall presents something like a „wall“ between a computer and network. Firewall protects your computer before attacks of hackers and also controls datas.
Allows you to decide, if you permit to some programe ans access to the internet or not. Some firewalls warn a computer, if some program is running without your approval
Hardware
=external computer equipment
- indicates all of the physically existing technical equipment of computer. Hardware are components of computer without which they wouldn’t be able to work. These are electronic components that are on the base unit, sometimes called a motherboard on mainboard. The motherboard is the basic hardware of the most computers. A source is a hardware powered from the electrical net, which dirrects a current to the base unit and to the other hardware components that are not directly involved to some of the buses on the base unit and need the power to run.
Typical parts of Hardware
processor, memory, display, keyboard, printer, diskettes, drives, CD-ROM drives, tape drives, speakers…
Software
= internal computer equipment
set of all computer programs, which are used in computers which provide some operation. Software can also provides an unintended operation and in this case we are talking about programming error or computer viruses, malware, spyware, trojan horses and similar unwanted software.
Software can be divided by functions:
- System software = allows effective usage of computer
- Firmware = software contained in Hardware (BIOS, firmware input-output divices)
- Operating system = manages computer (creates environment for programes
- System tools = for the management of operating system
- Application software
- Graphics programs
- entertainment software: computer games…
http://hardwareasoftware.sweb.cz/
Free software vs Paid software
Free software
is computer software that gives users the freedom to run the software for any purpose as well as to study, change, and distribute the software and the adapted versions
Clearly said – Free software refers to a freedom, not to price.
- The freedom to run the program for any purpose
- The freedom to study how the program works, and adapt it to your needs
- The freedom to redistribute copies so you can help your co-worker
- The freedom to improve the program and publish the improvements to them can benefit the whole community
Examples:
- 7-Zip – Zipping and unzipping software that is truly free
- Firefox, Chrome – browsers
- VLC, MediaPlayerClassic – Video
- Spotify – Music
- Picasa – Photo Editor
http://www.gnu.org/philosophy/free-sw.cs.html
http://unlearner.com/toolbox/70-best-free-alternatives-to-paid-software/
http://lifehacker.com/paid-vs-free-software-your-best-arguments-870361592
https://cs.wikipedia.org/wiki/Svobodn%C3%BD_software
Paid Software
While the distinction between free and paid software almost seems irrelevant when you consider quality, it does matter in terms of support.
When you pay for software, you generally get the support systems that go with it — regular upgrades, software publishers who are more interested in what you want to do with the software than what they want to do with it, and more responsive technical support. Plus you get that God-given right to say „I’ve got a problem with your software, and I’d like your assistance in fixing it.“
There are exceptions to everything, of course. But in general, when it comes to software support systems, you get what you pay for.
Examples:
- Microsoft Office
- AutoDesk software
- Adobe content creation software
- MATLAB
Network attacks
Network attack is any attempt to destroy, change, stole or gain unauthorized access or unauthorized use of property by means of computer technology and computer networks.
Attack can be active or passive, inside or outside
By active attacks we are trying to change the system resources or affect their operation.
By passive attack, we are trying to learn or use the information from the system, but has no influence on system resources.
Types of attacks:
-
- Network
- wiretapping
- Port scanner
- Idle scan
- Network
- Active
- Denial-of-service attack
- Spoofing
- Network
- Man in the middle
- ARP poisoning
- Ping flood
- Ping of death
- Smurf attack
- Host
- Buffer overflow
- Heap overflow
- Stack overflow
- Format string attack