physical layer: Layer for actual data transmission over physical mediums
script kiddies
mostly teens without much technical expertise who use downloadable software or source code to perform malicious break ins.
encryption
the process of encoding a message so that its meaning is not obvious
Wide area networks (WAN)
communication network that covers a wide geographic area, such as a country or the world.
Infrared Transmission
Infrared wireless transmission sends data signals using infrared-light waves at a frequency too low for human eyes to receive and interpret
The second layer of OSI
Data Link layer: Manages data packet transmission within the same network
Hactivists
break into computers for politically or social motivations
decryption
the reverse process of encoding a message so that its meaning is not obvious
Metropolitan area Network (MAN)
is a communications network covering a city or a suburb
Broadcast Radio
When you tune into AM or FM radio stations, you are using broadcast radio, a wireless transmission medium that sends data over long distances at up tp 2 megabits per second- between regions, states or countries.
The third layer of OSI
Network Layer: Handles routing and addressing for inter-network communication
Black hat hackers
break into computer systems to steal or destroy information or to use it for illegal purposes
Plaintext
the original form of a text
Local Area Network (LAN):
connects computers and devices in a limited geographic area such as one office, one building, or a group of buildings close together.
Cellular Radio
widely used for cell phones and wireless modems, using high frequency radio waves to transmit voice and digital messages.
fourth layer of OSI
transport layer: Ensures reliable end-to-end data delivery
Cyber terrorists
politically motivated persons who attack computer systems so as to brung physical or financial harm, or destroy information
Cipher text
the encrypted form of a message
Home Area Network (HAN)
uses wired, cable, or wireless connections to link a household’s digital devices.
Microwave Radio
transmits voice and data at 45 megabits per second through the atmosphere as super high frequency radio waves called microwaves, which vibrate at 2.4 gigahertz (2.4 billion hertz) per second or higher.
Fifth layer of OSI
Session Layer: Establishes, manages, and terminates application connections
white hat hackers
break into computer systems and networks to expose security flaws that can then be fixed.
Cryptography
achieving security by encoding messages to make them non-readable
Personal Area Network (PAN)
uses short range wireless connections to link a household’s digital devices.
Communication Satellites
are microwave relay stations in orbit around the earth. Transmitting a signal from a ground station to satellite called uplinking: the reverse called downlinking