3.1 B Network Topologies Flashcards
Point-to-Point
Two Networks connected
Bus
Where every device is connected to a single cable that runs from one end of the network to the other.
Pros:
–> Easy installation
–> Fewer cables
–> Easy to manage and expand
Cons:
–> Easily congested on busy periods
–> Efficiency decreases rapidly with each added node
–> Data can only transfer in one direction
Star
Consists of One central Node to which all other nodes are connected
Pros:
–> Durable
–> Easy to manage from one point
–> Easy to add and remove nodes
Cons:
–> Requires specialist network hardware (the switch)
–> A finite number of switch ports limits the network’s size
Ring
each device is connected to two other devices (Coaxial cable)
Pros:
–> Low cost
–> Low incidence of collision
Cons:
–> One faulty node will bring the entire network down
–> Performance declines rapidly with each additional node
Mesh
All devices in the network are interconnected
Pros:
–> High speeds data transfers
–> Very secure
–> Easy to identify faulty equipment
Cons:
–> Requires a very large amount of cable
–> Takes a long time to set up
Tree
structure that is shaped like a tree with its many branches. Tree topologies have a root node that is connected to another node hierarchy
Pros:
–> Easy to expand
–> Easy to manage
Cons:
–> Involves a lot of cable
–> The network is dependent on the health of the root node
Fully Connection
A network topology in which there is a direct path (branch) between any two nodes
Hybrid
Composed of two or more different topologies
Pros:
–> Very flexible
–> Infinitely extendible
–> Adaptable to optimize equipment use
Cons:
–> Requires professional management
–> Needs monitoring software
–> Equipment costs are high
Wireless Networking
Devices communicate and exchange data through r radio
Pros:
–> Installing cables can be expensive
–> Easy to set up a temporary link
–> A lot of public access points exist
Cons:
–> Health Concerns (radio waves)
–> Relatively low speed
–> High error rates
Social, and Environmental Issues
Social:
–> Cellphones cause 26% of all motor crashes
–> Creates comfort, convenience
Environment:
–> Tech Devices contain hazardous materials (‘g. mercury and lead)
–> Active mobile users ( 7.3 billion in 2014)
Wireless Network Adapter
Required for each device on a wireless network
Wireless Antennas
Access points and routers frequently utilize WI-FI antennas that significantly increase the effective communication area of a wireless network.
–> Antennas are fixed, optional, and removable
Wireless Repeater
(Signal boosters or range expanders) Connects to a router or access point and to rebroadcast it
Ethernet to Wireless Access Point or Wireless Access Point to Ethernet
It uses Ethernet cables to carry the signal to the wireless repeater or WAP
Ethernet over Power line to Wireless repeater or WAP
Uses Power lines to carry the signal to the wireless repeater or WAP
DHCP
Dynamic Host Configuration Protocol
Network Protocol that allows a server to automatically assign an Ip address to a client device.
Software Firewall
Network Security system that determines what data comes in and goes out of a network or a PC.
Name/ SSID
Service set identification is a set of 32 alphanumeric characters.
Used to differentiate one WLAn from another
NIC Drivers
Network Interface Card Driver
Operates or controls the hardware of the card. Acts as a translator between the wireless card and the application or OS of the device
OS
Operating System
Handles system resources and is responsible for managing all protocols, hardware, and applications that have to cooperate in order for the network can exist
Security Software
Software that prevents unauthorized:
–> Access
–> Use
–> Disclosure
–> Modification
–> Modification
–> Recording
–> Destruction
WAP
Wireless Application Protocol
Specifies a set of protocols for accessing information over a mobile wireless network.
Web Browser
Application Software that is used to find retrieve and display content on the world wide web
(eg. image, audio, video, other web)
Bit Rates
Kilobit per second (kbits/s) –> 10^3
Megabit per second (Mbit/s) –> 10^6
Gigabit per Second (Gbits/s) –>10^12
1G/2G
First Gen of mobile technology
Used Analog Transmission.
3G
Widely used in telephony
GPS
Video Calls
Mobile TV
Transfer rate of 200kbit/s
More Secure than 2G Networks
4G
Mobile Internet access for laptops, smartphones and other devices
Transfer Rate of 100 Mbit/s
LTE
Long Term Evolution (4G network) is also a wireless communication of high-speed data
Transfer rates of 300 Mbit/s
Upload rates of 75 Mbit/s
WiMax
Telecommunications technology aimed at providing wireless data over long distances in a variety of ways
Sensor Network
Measures data and parameters such as temperature, sound, and pressure for physical and environmental reasons.
WiMAX v.s LTE
Both are 4G technologies
Both are Ip Technologies
They use different channels
LTE is compatible with 2G and 3G whereas WiMAX isn’t
LTE is more expensive
Encryption
Protects data from unauthorized access during internet use or any other untrusted network.
Uses Complex mathematical algorithms and encryption keys to alter a message into a form that is not understandable to an unauthorized person.
- Symmetric-Key Encryption
- Public-Key Encryption
Symmetric-Key Encryption
The same key is used for encryption and decryption.
The same key is used by both the sender and the recipient of the message.
Pros:
–> Secure data transmission
–> Relatively fast and efficient
Cons:
–> The key needs to be distributed securely among many users
–> If the key is compromised, all the encrypted data is at risk.
Public-Key Encryption
Uses a pair of keys to encrypt and decrypt data. First key with owner and second key is public
Pros:
–> Secure
–> Eliminates the need for secure key exchange between sender and recipient
Cons:
–> slower and more computationally intensive
Free Access
Wireless data transmission extends beyond walls and window screens.
