1.3.2 Networks

two or more computers connected together that transmit data

the physical layout of the network

topology that describes the flow of data through a network

topology in which all terminals are connected to a backbone cable

cheaper to set up, doesn’t require any additional hardware

if backbone cable fails, entire network gets disconnected, as traffic increases, performance decreases, all computers can see data transmission

network which uses a central node to direct the flow of data, each terminal is connected to the central node

performance is consistent with heavy network usage; f one cable fails only that station is affected; transmits data faster, so it gives better performance; it’s not difficult to add new stations; no data collisions

expensive due to switch and cabling, if the central switch fails the rest of the network fails

topology in which every node is connected to every other, most commonly found with wireless technology

no cabling cost; as number of nodes increase, reliability and speed increases; new nodes automatically get incorporated; faster since data doesn’t travel through a central switch

need to purchase devices with wireless capabilities, maintaining the network is difficult

sets of rules defining how two devices communicate with each other

so devices from different manufacturers don’t have problems communicating

a global network of interconnected networks

transmission control protocol

internet protocol

specifies what protocols need to be used to relate the application to what it’s being used for

establishes an end-to-end connection between the source and recipient computers, it also splits up the data into packets

adds the source and destination IP address

presents data in the form it was sent

removes the port number and reassembles the packets

removes the IP address

removes the MAC addresses

a network spread over a small geographical area

a network spread over a large geographical area, usually requiring extra hardware

domain name system

name given to the method of naming internet resources

process of creating a direct link between two devices and transferring data the entire duration of the link

transfer and download rates must be identical on both devices

a method of communicating packets of data across a network

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

time is spent deconstructing and reconstructing the packets

data arrives in logical order which results in a quicker reconstruction of data; enables two users to hold a call without any delay in speech

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

the sender and recipient IP addresses, protocols being used, order of the packets, the time to live/hop limit

the raw data

checksum or cyclic redundancy check

a relationship between terminals (computers) and a single server which allows them to communicate, and share resources

increased security, central single backups, data and resources can be shared

expensive to set up, trained staff are required to maintain the network

network where the terminals are all connected to each other to share resources

cheaper to set up, easy to share resources, easy to maintain

can be used to contribute towards piracy, each computer has to be backed up independently