Is a device which is used to control the flow of
data to and from a computer.
Usually exchange data from a modem or
other serial cables.
Is often modems
Is used to create a session, maintain it, and
terminate between two devices to transfer
It also coverts signals for transmission.
Is a mobile phone standard by ITU, one
feature is to connect to mobile broadband.
This allows the user to connect to the
internet to transfer data.
Has a maximum download speed of 7.2Mb
and a download speed of around 2Mb
It works by phone towers send signal to each
other and then the closest one to the phone
send it to that phone.
Is a newer version of 3G mobile standard by
It allows faster speeds than 3G meaning
things that were difficult/ slow to use like
streaming video will be easier on 4G.
Has a download speed of around 50 Mb and
upload speed of around 14 Mb
However it only works for new phones and
where there are 4G phone towers.
Can allow users to call and send text to other
people with mobile phones.
It can also communicate with Bluetooth and
if it has access to the internet, depending on
the phone it can send E-mail, access social
networks and download data like pictures
Is a portable computer that can connect
wirelessly to routers, or hotspots to access
internet or transfer data.
It can also connect and transfer data to other
devices using Bluetooth.
Tablets are just like laptops, they both
communicate the same ways, they are both
portable, the only major differences tablets
don’t have a built in keyboard and touchpad,
might have a connectable one, it’s touch
screen and has less memory.
Tablets are mostly used on the go.
Speeds of around 70 kilobits per second
Is used to transfer data mostly used on 2G
phones, with this the phone must stay on and
can send data during calls.
This can be added to new phones but is slow
compared to 3G and 4G.
Is a devices used to connect and convert data
from a digital line to a network or device.
Is where signal/data is sent from one device
to another but can only go in one direction
meaning data can’t be sent the same way it
For example aTV stations transmits data to
the receive your house to view the channel
but nothing is sent back to theTV station.
Half duplex is where you can send and receive
data from devices at any time, however both
devices can’t send them at the same time.
Full duplex is just like half duplex where two
devices can send data but full duplex allows
both devices to send at the same time
without any collisions.
This is because the data link layer ensures
both are able to send and receive data at the