Terminologia

Term	Definition
Address resolution protocol (ARP)	a communication protocol used for discovering the link layer address, such as a MAC address, associated with a given internet layer address, typically an IPv4 address. Layer 2. In IPv6 networks, the functionality of ARP is provided by the Neighbor Discovery Protocol.
Availability	Availability is a measure of the % of time the equipment is in an operable state. It can be measured as: Uptime / Total time (Uptime + Downtime).
Availability vs Reliability	While Availability is a measure of the % of time the equipment is in an operable state, then reliability is a measure of how long the item performs its intended function. For example a machine is down 6 minutes every hour. This translates into an availability of 90% but a reliability of less than 1 hour. Reliable machine has high availability. But an available machine may or may not be very reliable. Font is: ´Understanding the Difference Between Reliability and Availability <https://reliabilityweb.com/tips/article/understanding_the_difference_between_reliability_and_availability/>´_.
Data Circuit-terminating Equipment	a device that sits between the data terminal equipment (DTE) and a data transmission circuit. Usually, the DTE device is the terminal (or computer), and the DCE is a modem.
Data terminal equipment	Terminal: converts user information (characters from keyboard) into signals. Or reconverts received signals in user informations (characterss on monitor).
Datagram	A self-contained, independent entity of data carrying sufficient information to be routed from the source to the destination computer without reliance on earlier exchanges between this source and destination computer and the transporting network (RFC 1594)
egress	On Switching. It is where frames leave the device from a particular port.
End devices	provides an interface between the human and the network.
ingress	On Switching. It is where a frame enters the device on a port.
interface	porte specializzate in un networking device che connettono reti individuali (di solito, nei router)
Intermediary devices	provides connectivity and ensures data flows across the network.
LAN adapter	vedi Network interface card
latency	tempo, incluso i ritardi, necessario perché i dati viaggino da un punto della rete ad un altro
Network media	provides a channel for messages to travel from source to destination.
Network interface card	(NIC) fornisce la connessione fisica dell’end device alla rete
physical port	connettore di un network device dove viene collegato il mezzo di trasmissione
Reliability	Reliability is a measure of the probability that an item will perform its intended function for a specified interval under stated conditions. There are two commonly used measures of reliability: Mean Time Between Failure (MTBF), which is defined as: total time in service / number of failures Failure Rate (λ), which is defined as: number of failures / total time in service.
Shell	The user interface that allows users to request specific tasks from the computer.