2. Networks Flashcards
what is a router?
routes data packets between different networks.
what can a router do?
- connects networks together
- manage and priories data traffic
- assign IP addresses to devices.
what are data packets?
small chunks of data that make up a larger piece of data, that has been broken down so it can be transmitted over the internet.
what do data packets consist of?
heard
payload
trailer
what does a header have/do
has source of IP address
Destination IP address
Packet number (1of 5 etc.)
Error checking
What does a payload have
actual data being transported
what does a trailer have
additional security information
end of packet notification
what is an IP adress
a unique identifier given. to devices which communicate over the internet
characteristics of IP address
dynamic, can change
silver data to the right device
address changes when connected to a different network
what is IPv4 and IPV6
unique addresses
what’s a NIC
Network Interface Card
so a computer can connect to a network
can be wired or wireless
allows the computer to send and receive data over a network
What is a hub?
a networking device used to connect multiple devices in a network
what a disadvantage of a “hub”
passes any info received on 1 connection to all connections.
leads to inefficiencies and security issues
what is a switch
a network device that connects multiple devices on. a network together
difference between switch and hub
only sends data to the device it was intended for, improves network efficiency
How do switches work
- when switch receives the data packet, it examines the destination MAC adress.
- Looks it up on the lookup table.
- Once found the matching adress, it forwards the data packet.
What is a MAC address?
Media Access Control
unique identifier given to devices which communicate over a LAN
characteristics of a MAC address
static, never change
helps switches forward data
any device that has a NIC has a MAC
what is a bridge?
a device used to connect 2 LAN’s together to create one larger network.
Unlike switch/hub, only connects LAN’S together.
what is a wireless network
a network where connections are made using radio waves to transmit data through the air
what are the common types of wireless connections
Wi-Fi
Bluetooth
What is WiFi
wireless network
common in homes
why would wifi be preferred over bluetooth
High speed data transfer is required
Long range communication is required
Many devices are needed to be connected at the same time
adv of wifi
Portability - Easy to move around, location is only limited by range
Cost - Less expensive to setup and add new devices
Compatibility - Most devices are manufactured with a built in Wi-Fi adapter
dis of wifi
Speed - Slower data transfer than Ethernet
Security - Less secure than Ethernet
Range - Relies on signal strength to the WAP, signals can be obstructed (up to 100m)
what is bluetooth
wireless network
common in homes
used for direct connection between 2 devices.
adv of bluetooth
Compatibility
Power - Very low power consumption
dis of bluetooth
Speed - Very slow transfer speeds
Security - Data can be intercepted by anyone in range
Short range (30m)
difference between wifi and bluetooth
no of connections : 30,7
range: 100m,30m
transfer speed: 75Mbytes, 3Mbytes
what is cloud storage
long-term storage of data that resides in a remote location, accessible only via Internet
where is data stored
on remote serves, SSD
what is public cloud
The customer and the cloud storage provider are different companies
what is private cloud
The customer and the cloud storage provider are a single organisation
whats is hybrid cloud
Combines both public and private cloud options
allows for sensitive data to remain private whilst providing public cloud services for less sensitive information
adv of cloud storage
Data can be accessed from anywhere
Data can be accessed by anyone with the relevant permissions, making it quick to share files and collaborate with others
Data can be accessed on any device with an internet connection
Allows customers to increase or decrease their storage capacity as needed
Providers often use multiple servers to store and backup data, reducing the risk of data loss due to hardware failure
dis of cloud storage
A stable internet connection is required to use cloud storage
Storing data in the cloud may be vulnerable to security breaches
The user is dependent on the storage provider for the availability and reliability of its services
as storage increases, service more expensive
what is the internet
is a global network of networks
what is WWW
collection of websites and web pages that are accessed using the internet
what is an intranet
operate only within a local area network (LAN)
characteristics of an intranet
provide companies with a secure platform
resources exclusively with their employees
private
advantages if intranet over internet
Better bandwidth than the internet
Data is kept within the organisation
Less chance of hacking and attacks
Administrators can manage access to external sites and links
what is an extranet?
allows authorised access from outside of the local area network
who are extranets useful for?
Customers
Clients
Key stakeholders
whats the similarities between internet, intranet, extranet
They are all web based technologies
They allow users to access information remotely
They all use client server architecture
They all use security measures such as authentication and encryption
They all promote and facilitate information and resource sharing
what is a network?
two of more devices connected together with the purpose of sharing resources
what are the 3 types of networks?
Local Area Networks (LANs)
Wireless Local Area Networks (WLAN)
Wide Area Networks (WANs)
What is a local area network?
(LAN) is a network which has a small geographical area
All of the hardware is owned by the company using it
adv of LAN’s
Allows centralised management
Can secure its devices with the use of firewalls to prevent unauthorised access
Allows users on the network to share resources such as printers and other peripherals
Allows the users of the network to collaborate and share files and folders
dis of LAN’s
If hardware fails, the network may not function properly
more prone to attacks than standalone computers
Access to data and peripherals can be slow depending on network traffic
Require maintenance to ensure that software is up to date, upgrades and backups which can be costly
What is a wireless local area network?
s a local area network where devices connect to the network wirelessly instead of using cables
adv of WLAN
Allows users to connect anywhere that is in the range of a Wireless Access Point (WAP) without the need for additional hardware or wiring.
Can be used in a variety of environments both indoors and out making them highly flexible
Additional wireless access points can be added relatively easily resulting in additional users being able to use the network or increased network coverage
Access to peripherals such as printers
dis of WLAN
Limited in their coverage and can be further affected by walls and other structures
Bandwidth speeds can become an issue in high traffic areas
Interference from other devices which can affect performance and connectivity
Vulnerable to security threats due to wireless signals being intercepted
What is a WAN
a network which has a large geographical area
characteristics of a WAN
They are a collection of LANs joined together
The computers on a WAN are connected via routers
The hardware used to connect the networks together is not all owned by the company using it.
The transfer of data on a network poses potential security risks, such as:
Unauthorised access
Data manipulation
Common causes of data transfer security risks
Hackers
Insider threats
Social engineering
Unencrypted transfers
Weak encryption
Insecure protocols
What are passwords?
are a digital lock to prevent unauthorised access to an account
encrypted/ciphered
ensure passwords are strong
periodically changed
What is authentication?
the process of ensuring that a system is secure by asking the user to complete tasks to prove they are an authorised user of the system
why is authenication used?
bots can submit data in online forms
how to authenticate
Zero login & biometrics
Magnetic stripe
Smart cards
Physical & electronic tokens
what is zero login & biometrics
Allows a user to login without using a username & password
Uses biometric data (fingerprint, face, gestures) to create a profile of a user so that they can log in without having to authenticate each time
adv of zero logs & biometrics
Convenient for devices when users need to log in frequently throughout the day e.g. smartphones
dis of zero logs & biometrics
If compromised, biometric data cannot be changed
Biometric recognition can be less than perfect and lead to failed login attempts and user frustration
whats a magnetic stripe?
contains unique data used to authenticate a user e.g. ID, name & date of birth
When swiped through a magnetic card reader, details are used to identify a user
adv of magnetic stripe
Easy and cheap to setup
Cards can be used to access multiple systems
Cards can be remotely deactivated
dis of magnetic stripe
Magnetic stripes can wear
Card readers must be maintained
Less secure than biometrics
what is smart cards
Enhances a magnetic stripe cards with the addition of a microchip to create a contactless card
Microchip stores additional information such as a pin to add
extra layer of security
Data in encrypted
adv of smart cards
More secure than magnetic stripe cards
Multi-purpose
Transactions can be much faster
dis of smart cards
More expensive to manufacture
Lack of compatibility can cause inconvenience
what is a physical token
A physical device used to authenticate a user
generates a random (OTP) that a user must type in
Banks may ask customers to insert their bank card into the device and use the OTP to access internet banking
OTPs change after a few minutes
adv and dis of physical token
Very secure
Inconvenient to the user as they need a physical device, card and login credentials to access one site
what is electric token
Software token generated by an app
App generates OTPs
Users authenticate in app e.g. fingerprint and OTP is generated
adv of electric token
Very secure
More convenient
What is anti-malware software?
is a combination of different software to prevent computers from being susceptible to viruses and other malicious software
The different software anti-malware includes
Anti-virus
Anti-spam
Anti-spyware
how does anti-malware work?
- scans through email attachments: to search for threats
- has a list of known malware signatures to block immediately if they try to access your device
- performs checks for updates to ensure the database of known issues is up to date
- will quarantine infected files
What is video-conferencing?
is a way of enabling real-time audio and visual communication between geographically separated parties
Video-conferencing is typically used for:
Staff meetings
Presentations
what hardware is needed for video conferencing
webcam
microphone
Speakers
large displays
adv of video conferencing
Convenience
Cost saving
Better for the environment
Attendees do not have to travel to the event
Anyone within the company can attend regardless of location
Events can be held at short notice as travel is not required
Allows other members outside of the organisation to attend easily without having to visit on premises
Some video conferencing software allows record and playback to allow members to review the meeting
dis of video conferencing
The initial purchase of equipment can be costly
Possible issues amongst employees when working across different time zones
Those using the system may need to be trained to use it effectively which can:
Take time
Be costly
Video-conferencing systems require a strong and stable network connection
Poor picture/sound quality caused by the speed of connection/quality of the hardware
Delays (audio & visual) can disrupt the flow of the meeting
what is audio conferencing
real-time audio only communication between geographically separated parties
adv of audio conferencing
Cheaper than video-conferencing as less hardware is required
More accessible as less training is needed for participants
Gives participants the ability to focus only on voice and not get distracted by video
dis of audio conferencing
participants can lose focus due to lack of visual interaction
A lack of visual clues may lead to miscommunication
Audio quality can be poor
Does not suit collaboration
what is web conferencing
real-time audio and visual communication between geographically separated parties on the internet
adv of web conferencing
Pre-shared/downloadable presentation notes/slides
Participants can use instant messaging within conference to ask questions
Collaboration via virtual ‘whiteboards’
Screen sharing/annotations
dis of web conferencing
Technical issues usually relating to participant internet connections
Security concerns, risk of data interception
Distractions
Some users may feel overloaded with information which can lead to a lack of focus
