fundamental of communication and networking Flashcards
symbol
a particular pattern of bits represented by a signal
baud rate
the number of signal changes in the medium per second
bit rate
the number of bits that are transmitted over the medium per second
bandwidth
the range of frequencies that a communication medium is capable of transmitted
latency
the difference in time between action being initiated and its effect being noticed
protocol
a set of rules relating to communication between devices
serial data transmission
data is sent one bit at a time
parallel data transmission
numerous parallel communications lines send multiple bits between components simultaneously
crosstalk
signals from the tightly packed communication lines can leak into others
skew
each of the lines will have slightly different electrical properties
adv of serial
doesnt suffer from skew / crosstalk
synchronous transmission
a clock signal is shared by both the reader and the receiver
the signals sent at regular intervals will be received in the same order sent
asynchronous transmission
start and stop bits are used to indicate the duration of a transmission
the start bit can either be 1 or 0. stop bit must be opposite
what does asynchronous data require?
same baud rate
synchronise clocks
two types of physical network topology to learn
bus + star
client server networking
one of more central servers provide services to the client on the network
allows central management
peer to peer
do not use shared server
services are provided by the clients themselves
an ssid
is a name that identifies a wireless network
mac address
assigned to every wireless device
csma
when device ready to send
listens to communication channel to see if its idle
rts/cts
request to send/ clear to send
requests to send first, if idle then yeah
