networks pmt flashcards
what is a network
two or more computers connected together that transmit data
what are protocols
set of rules defining how two devices communicate with each other
why are protocols standard
protocols are standard so devices from different manufacturers don’t have problems communicating
define the structure of the internet
the internet is a global network of interconnected networks
what does the TCP stand for
transmission control protocol
what does IP stand for
internet protocol
what is the function of the application layer during data transmission
the application layer specified what protocols need to be used to relate the application to what its being used for
what is the ole of the transport layer during data transmission
establishes an end to end to end connection between the source and recipient computers.It also splits up data into packets
what is the role of the network layer during data transmission
adds the source and destination IP address
What does the application layer do when it receives data
presents data in the form it was sent
what does the transport layer do when it receives the data
removes the port number and reassembles the packets
what does the network layer do when it receives the data
removes the IP address
what does the link layer do when it receives the data
removes the MAC addresses
what is a local area network
a network spread over a small geographical area/ positioned on a single site
what is a wide area network
a network spread over a large geographical area , usually requiring extra hardware
what does the DNS stand for
domain name system
what is the DNS
the name given to the method of naming internet resources(.com , uk)
what is circuit switching
the process of creating a direct link between two devices and transferring data the entire duration of the link
what is a requirement of circuit switching
the transfer and download rates must be identical on both devices
what is packet switching
a method of communicating packets of data across a network
give an advantage of packet switching
-multiple methods to ensure data arrives correctly
-multiple methods to arrive to destination, if one breaks you can always go through another route
-transfer packets over a very large network
give an disadvantage of packet switching
time is spent deconstructing and reconstructing the packets
give an advantage of circuit switching
data arrives in logical order which results in a quicker reconstruction of data
-enables two users to hold on a call without any delay in speech
give two disadvantages of circuit switching
-bandwidth is wasted during periods when no data is sent
-devices must transfer and download at the same rate
-switches introduce electrical interference which can corrupt or destroy data
what does the header of a data packet contain
-the sender and recipient IP address
-protocols being used
-order of the packets
-the time to live
what does the packet payload contain
raw data
what does the packet trailer contain
checksum or cyclic redundancy check
what is a client server networking
a relationship between terminals (computers) and a single server which allows them to communicate and share resources
give an advantage of client server networking
-increased security
-central single backups
-data and resources can be shared
name a disadvantage of client server networking
-expensive to set up
-trained staff are required to maintain the network
what. is a peer to peer network
a network where the terminals are all connected to each other to share resources
give two advantages of peer to peer networks
-cheaper to set u
-easy to share resources
-easy to maintain
give tw disadvantages of peer to peer networks
can reused to contribute towards piracy
-each computer has to be backed up independantly
