Data transfers over networks Flashcards
Bluetooth
Low energy use variant of bluetooth which allows for a mesh network
RFID Radio frequency ID
uses electromagnetic fields to read data stored in embedded tags.
NFC Near field communication
Enables two electronic devices to communicate within 4 cm range
Infrared IR
Operated within line of sight
Z-wave
Provides short range, low latency data transfer with slower rates and less consumption than wifi used with home automation
ANT+
Collection of sensory data tire pressure sensor
Broadband
Divides width into separate channels (cable tv)
Baseband
Uses all available frequencies on a medium cable to transmit data and uses a reference clock to coordinate the transmissions by both sender and receiver.
Logical Link Control (LLC)
Provides connection services and allows acknowledgement of receipt of messages. Basic form of flow control.
provide basic error control functions.
Media Access Control (MAC)
Physical addressing system that uses a 48 bit address assigned to a network interface card (NIC) by manufacturers.
Logical addresses
Numerous routed protocols were used for logical addressing over the years but only internet protocol (IP) remains dominant.
Route Discovery and selection
Manually configured as a static route or dynamically through a routing protocol.
Internet control message protocol (ICMP)
Used to send error messages and operational information about an IP address.
UDP User Datagram Protocol
Connectionless protocol that is an unreliable way to transport segments across the network. If dropped sender is unaware but really good for audio and visual streaming.
TCP Transmission control protocol
Connection oriented protocol that is a reliable way to transport segments across the network.
N map (Network Mapper)
Command line tool that maps the network.
Link Aggregation 802.3ad
Allows for a combo of multiple physical connections into a single logical connection. With this, bandwidth available is increased and the congestion is minimized or prevented.
Power over Ethernet (POE 802.3af, POE+ 802.at)
Supplies electrical power over ethernet and requires CAT5 or higher copper cable. (poe 802.af can put up to 15.4 watts of power to that device.)
(POE+ 802.at can put up 25.5 watts of power.)
User Authentication
802.1x
For security purposes, switches can require users to authenticate themselves before gaining access to the network. Once authenticated, a key is generated and shared between the supplicant(device wanting access) and the switch (authenticator)
Data Formatting
Data if formatted by the computer to have compatibility between different devices.
ASCII American Standard Code for Information Interchange
Application Services
Unite communicating components from more than one network application.
Circuit switching
dedicated communication link is established between 2 devices.
Message switching
data is divided into messages similar to packet switching except these messages maybe stored then forwarded.
Windowing
Allows the clients to adjust the amount of data sent in each segment and continually adjusts to send more or less data per segment transmitted.
Packet switching
Known as “routing” where data is divided into packets and forwarded.
Connection services
Layer 3 augments layer 2 to improve reliability.
flow control and packet reordering.
Transmission Modulation
If it changes during the clock cycle, then a 1 is represented (otherwise it is a 0 “zero”
Buffering
Occurs when devices, such as routers, allocate memory to store segments if bandwidth isn’t readily available.
Service Advertisement
This is where applications send out announcements to other device on the network to stat the services they offer.
Encryption
used to scramble the data in the transit to keep it secure from prying eyes and provides confidentiality of data.
Reference #
- Categorize functions of the network into particular layers.
- Compare technologies across different manufacturers.
- Understand how to best the communicate with that device.
Ad Hoc Mode
Decentralized wireless network which creates peer to peer connections and does not require a router or access point.
Infrastructure Mode
Uses WAP wireless access point as a centralized point like a star supports wireless security controls and centralized management.
asynchronous
Network devices reference their own internal clocks and use start/stop bits. Uses start bits and stop bits to indicate when transmissions occur from sender to receiver. EX Voicemail.
Synchronous
Network devices agree on clocking method to indicate beginning and end of frames and can use control characters or separate timing channels.
uses a reference clock to coordinate the transmissions by both sender and receiver.
Isochronous
Network devices use a common reference clock source and create time slots for transmissions with less overhead than synchronous or asynchronous methods.
