4.9.2 Networking Flashcards
What is a physical star topology?
A star network has a central node, which may be a switch or a server which acts as a router to transmit messages across the network
What is a logical bus topology?
Data cannot be transmitted in both directions. Every station receives all network traffic, and the traffic generated by each station has equal transmission priority. A device wanting to communicate with another device on the network sends a broadcast message onto the wire that all other devices see, but only the intended recipient actually accepts and processes the message.
What is peer-to-peer networking?
In a peer-to-peer network, there is no central server. Individual computers are connected to each other, either logically or or a wide area network so they can share files
What is client-server networking?
In a client-server network, one or more computers known as clients are connected to a powerful central computer known as the server. Each client may hold some of its own files but can also obtain and upload files onto the central server.
Where would peer-to-peer networking be set up and why?
In a small local area network, such as a home or small office, a peer-to-peer network is a good choice because it:
Is cheap to setup,
Enables users to share resources such as a printer,
Is not difficult to maintain
Where would client-server networking be used and why?
Large offices will use client-server networking because:
Security is better since all files are stored in a central location
Backups can be done centrally at the server
Data and other resources can be shared
However, client-server networks are expensive to install and maintain because professional IT staff are needed to keep it maintained
Explain the purpose of WiFi
This means devices can move freely around a network without a wire
What components are required in order to connect to a wireless network?
A wireless local area network enables any device with a wireless network adaptor to connect to the internet via a wireless network access point (WAP) that is connected to a router
How are wireless networks secured?
Strong encryption of data using WPA (Wireless Protected Access) or WPA2.
MAC white lists are used to only allow people to connect who have authorised.
Disabling your SSID broadcast will make your network invisible when people are trying to connect to nearby wireless networks
How does the CSMA/CA protocol work?
This protocol attempts to avoid collisions occurring on a data channel. Prior to transmitting, a node first listens for signals on the network and if it is clear then it will transmit its data. Else, it will wait a random amount of time before attempting to transmit the data again. If there is still traffic on the network then it will wait the same amount of time as last time as well as another random wait time on that.
What is RTS/CTS?
When the device detects that the network is available for transmission, the device will send a RTS (Request to Send) to the WAP and the WAP will send back a CTS (Clear to Send) if the channel is idle
Is CSMA/CD required in Ethernet?
Collision detection in Ethernet is not required for a wired LAN
What is the purpose of Service Set Identifier (SSID)?
An SSID is the informal name of the LAN. The purpose of the SSID is to identify the network