Network Security
What does WLAN stand for
wireless local area network
What is an OSI (Open Systems Interconnection) model?
the blueprint for how computers talk to each other over a network.
What is a packet?
A unit of data that is routed between an origin destination on a network.
What does VPN stand for?
Virtual Private Network
What is the purpose of a firewall?
Describe one disadvantage of a wireless network
Hackers
Limited Range
Interference
Health Concerns (radiation)
What is the layer the user interacts with (The final layer)
Application
Header, Payload
What is the purpose of a VPN?
Allows the user to access networks remotely by encrypting the connection
Name 1 software component in wireless networking
network operating system
protocol stack
applications
What is the first layer in the OSI model?
Physical (media)
Name two pieces of information stored in the header of a packet.
The origin address and destination address, and the header length, timestamp
What are the two fundamental VPN technologies and their definitions?
Encryption: encoding data with a key that only the user can access
Tunnelling: encapsulating one data transmission protocol within another so the data can travel securely.
Describe the three factors in three-factor authentication?
1: something you know (password)
2: something you have (phone number/email/card)
3: something you are (biometric/finger/retina)
List 2 hardware components in a wireless network
NIC
node (computer)
radio waves
router
List four different layers of the OSI model.
Application
Presentation
Session
Transport
Network
Data Link
Physical
What happens to a the data as it is transported from the origin to the destination
It is pulverized into packets at the origin, then transported through various routes and reorganized and reassembled at the destination.
What are the four requirements for a VPN
A LAN with internet connection
A computer outside the LAN with a connection
VPN client and server running on both networks
Internet Connection
List 3 disadvantages with encryption security
users make easy passwords
some encryptions have built-in backdoors
passwords needs to be sent through a network to the user
What is a feature of 4G wireless that other generations do not boast?
HD streaming/HD phones, lightning fast connection
Name all the layers of an OSI model in order
Application
Presentation
Session
Transport
Network
Data Link
Physical
Explain the difference between lossy and lossless compression and the way these methods are carried out in the process of packet switching
Lossless Compression
Nothing is lost — all original data can be perfectly restored.
Looks for patterns or redundancies in data (like repeating letters or numbers).
Decompression restores the exact original data.
Lossy Compression
Some data is permanently removed — can't get back the original exactly
Removes data that's less noticeable to humans (like subtle colors or sound frequencies).
Achieves much smaller file sizes than lossless methods.
Ex. Audio and Video