Communication Protocols Flashcards
what is a transmission protocol/internet protocol?
its a set of protocols defining how information is split into packets and how packets are sent and received at the correct destination
what is TCP layer?
it supports the transfer of files between computer systems and controls security issues. it handles different character sets e.g. end of line conversation. it also splits data into packets and allocates an address to each packet
what is IP layer?
is responsible for transferring packets of data from node to node by forwarding each packet using its address. its responsible for verifying the correct delivery of data and detecting errors or lost data
what is ethernet?
it is a network protocol that controls how data is transmitted over a LAN. it defines not only the networking protocol, but the hardware, as well as how data is handled
ethernet implements physical and transport layers of OSI
what does stand for and what is it CSMA/CD?
Carrier Sense Multiple Access with Collusion
its a set of rules determining how network devices respond to a collusion which occurs when two devices attempt to use data channel simultaneously
how are ethernet and CSMA/CD connected together?
ethernet networks use CSMA/CD to physically monitor the traffic on the line between different computers on the network. if no transmissions is taking place at the time- the computer can start transmitting data
what happens when two computers attempt to transmit simultaneously?
this can cause collusion, which detected by all participating stations, after a random interval the computers that collided attempt to transmit again.
if another collusion occurs the time intervals from which the random waiting time is selected are increased
what is token passing?
uses a token, a special series of bits to give a device permission to transmit over the network
what happens when a device has a token
only when a device which has the token can put data into the network
when its transmission is complete the device passes the token along to the next device in the topology
what does the protocols have to do with token passing?
protocols determining how long a device may keep the token, how long it can transmit for and how to generate a new token if no token is currently in circulation
what is WiFi?
wireless fidelity
is a communications protocol, through which devices can communicate with each other without using any cabling
wifi enables two or more devices to connect for data sharing. wifi card can connect wirelessly to a wireless router over a limited distance
how does a wireless transmitter work?
the device receives information from the internet via the broadband connection. the transmitter converts information into radio waves and emits it, effectively creating a small, local area around itself , which the radio signals provided are fitted with the appropriate wireless adapter
what happens when you send an email?
the process works in reverse, the device send information via a radio signal and communicates it back via the broadband connection
what does a computer or phone have to have when connecting to wifi?
the relevant technology incorporated within it
what is a device that can connect to wifi from your device?
dongle
what is bluetooth?
its a short range technology aimed at simplifying communications among enabled devices
it also aims to simplify synchronization between devices
how do two bluetooth devices pair?
the device uses radio waves to connect to other devices.
bluetooth device contains a tiny chip with a bluetooth radio and software to enable it to connect with other devices
what is VoIP?
Voice over Internet Protocol
its a method of using the internet to make voice telephone calls. it converts analogue voice signals into digital data packets and supports real-time, two way transmission of conversations using Internet Protocol (IP)
what is digested speech?
its data and can be sent over the internet as with any other data, with widespread installation of broadband connections- data to be transferred fast enough to allow two way conversations
what is a RFID?
it involves the use of radio waves to read and capture information stored on a tag attached to an object
how far can a tag be read from?
it can be read from several feet away and doesn’t need to be within direct line-of-sight of the reader to be tracked
what does a RFID tag contain?
a data programmed into small computer chip and this tag is activated by radio waves emitted from an RFID reader
the tag sends data stored in its memory back to the reader
what sort of systems would RFID be used in?
used in active systems- whereby the chip has its own power supply
advantages of RFID
there is no line of sight requirement and RFID tags can be read from a greater distance
the information stored in a barcode is fixed and cannot be changed whereas RFID tags can be dynamically updated
human intervention is required in order to scan a barcode whereas data from an RFID tag can be read without the need for someone to properly align the tag with the equipment that reads the data
barcodes are usually visible on the outside but RFID tags can be placed inside either packaging or the product itself
more data can be stored in an RFID tag have both read/write capability whereas barcodes are read only and cannot be reused
