what is the use of a router
what specific tasks do routers do (3)
- a device that connects devices on a WAN
- recieve packets, transmit packets and assign IP addresses to devices
why is ethernet a standard (3)
- its used by all manufactorers
- high bandwidth
- low maintenance cost
what does a firewall do
scans incoming and outgoing traffic and blocks unauthorised traffic
how are analogue sound waves converted to a digital form (4)
- analogue sound wave sampled
- amplitude measured, at regular intervals
- each sample stored as a binary number
- binary number for each sample is stored sequentially
why do we use layers
- separate tasks can be developed independently on each layer
- able to group together similar protocols
- easier for coders to change one protocol without distrupting the others
what does a switch do
connects devices together on a LAN
and uses MAC address to route traffic to the correct device
LAN vs WAN (3)
meaning, area, owning
- local area network, wide area network
- covers a small geographic area, covers a large geographic area
- hardware for the LAN is owned by the organisation using it,
infrastructure is hired from telecommunication companies who own it
what does a single core 2.5GHz processor mean
single core means only one processor
2.5GHz means a 2.5 billions FDE cycles run per second
what does user management do (3)
- allows the setting up of accounts
- security / setting of password
- set different access rights
what does memory management do
- moves data between RAM and VM
- gets data from RAM
- stores data to RAM
what does utility system software do
Perform housekeeping/maintenance tasks
what are 3 cultural impacts
increasing digital divide, people feeling like their devices are out of data, increased employment to build devices
what will an internal secondary system store
software e.g operating system
network performance
what does a higher wifi frequency mean
what does more interference mean
shorter range so more limited to people
causes more errors so signals need to be retransmitted which makes more traffic
network performance
what does more users mean
what does the type of network mean
each user has less bandwidth causing more traffic
transmitting videos and larger files takes up more bandwidth
how is packet switching used to send data from one site to another (4)
packets have a fixed size
these are sent individually
packets are sent in different routers
receiving computer waits for all the packets then rearranges them back into the right order
3 things malware can do
steal data, change data and delete data
what does a DNS do
converts a website address (URL) into an IP address
wireless transmission media
wifi
bluetooth
uses radio waves to transmit data, as long as device has a NIC
uses radio waves and has a very short distance
advantages (3) and disadvantages (2) of mesh network
- message will always be able to go through since so many routes
- data can be transmitted from several devices simultaneously
- new nodes added easily
-very expensive
-many connections make it impractical to set up
advantages (2) and disadvantages (1) of star network
- reliable because if one cable fails other nodes are fine
-data collision are avoided - can be expensive for all the cables
-if switch fails all devices lose their network connection
what does peripheral management do
deals with inputs and outputs from connected devices
what does FTP do
file transfer protocol
transmits files between client and server computers
POP
post office protocol
retrieving emails from an email server to your device
deletes messages on email server once downloaded
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primary storage6
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secondary storage and virtual memory16
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fetch-decode-execute cycle19
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units of measurement8
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CPU architecture17
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wired/ wireless networks, network and topologies27
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data storage1
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protocols and layers14
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character sets, images, sound, compression6
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operating system11
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worst qs31
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computational thinking5
