5.1 network Flashcards
what is a network?
an arrangement of computers and other devices connected together to share resources and data.
what is a local area network (LAN)
A network that covers a relatively small geographical area , often a single site.
what is a wireless local area network (WLAN)?
a local area network in which connected devices use high frequency radio waves to communicate .
what is a wide area network (WAN)?
a network that covers a large geographical area. It connects together two or more LANs and is usually under collective ownership. the largest wide area network is the internet.
?what is a a client-server network?
a network that has at least one server to provide services to the client computers.
what is a peer-to-peer network?
a network that doesn’t have any centralised servers. Each computers in the network can act as client and server.
what is a network topology ?
describes how the devices on a network are connected together.
what is a internet?
a worldwide system of interconnected networks that enables information to be exchanged and shared.
what is a communication media?
the means by which data is transmitted between devices on a network. Coaxial cable, fibre-optical cable and microwaves are all forms of communication media.
what is a protocol ?
a set of rules that govern how communication on a network should be formatted and what data they should include.
what is a Eavesdrop ?
having unauthorised sight of data being sent from one computer to another over a network. This is covered more fully in the later section on technical weakness .
bandwidth
the amount of data that can be carried on a network in a given period of time
checksum
an error detection techniques. a mathematical formula is applied to the data and the resulting numerical value is transmitted with the data. the recipient computer applies the same formula to the received data and then compares the checksum sent with the data to the calculated checksum. if the checksum don’t match the data is likely to have been corrupted and the recipient computer requests the data again.
weserver
powerful computer system that store web pages and any multimedia that the pages might contain
network security
activities designed to protect a network and its data from threats such as service attacks,data interception and theft, and equipment failure
denial of service (dos)
an attack on a network that attempts to prevent legitimate users from accessing its services
access control
this determines which user have access to which data, and what they are allowed to do with it
hacking
the act of gaining unauthorized access to a computer system and data it contains
physical security
controlling access to critical parts of a networks using psychical methods (such as locked doors) rather than software
malware
short for ‘malicious software’. it is used as a generic term for any kind of software that is designed to disrupt the use of a computer system
USB
universal serial bus sockets found on most modern computer systems
serial transmission
uses a single wire to transfer the data bits
parallel transmission
uses several wires to transfer the data bits simultaneously
simplex transmission
data is sent in one direction only
