a set of rules governing the operation of some communications function
e.g. IP - rules for routing data
      TCP - rules for reliable, in-sequence delivery of data
protocol data unit (PDU) (a.k.a. packet)
a formatted unit of data that is terminated across a network. The information carried in a PDU is often called its payload.
protocol stack
a layered set of protocols that work together to provide communication between applications
e.g. TCP + IP + Ethernet
protocol suite
a familty of protocols that work together in a consistent fashion
e.g. TCP/IP
a computer that runs applications and has one or more users
(a.k.a. station, computer, computer system, PC)
A host that supports TCP/IP can act as an endpoint of communication.

a device that routes data through a network
(a.k.a. gateway, but gateways tend to perform some kind of protocol translation)
a set of network facilities connected by routers
a very special internet, connecting thousands of networks together
network node, network element, system:
a communication entity, but not necessarily a host
e.g. host, router, bridge, gateway, server
The goal of network management is to control and monitor all nodes in a network.
local area network (LAN)
a network covering a small geographical area
e.g. office, lab, campus
wide area network (WAN)
a network covering a large geographical area
e.g. city, state, continent
any medium over which nodes can communicate using a link layer protocol
e.g. Ethernet segment, PSTN, satellite, microwave
someone who has a high degree of computer or network skill
e.g.,  Robert Kahn, Vinton Cerf, Brian Kernighan, Dennis Ritchie, Ken Thompson, Bill Joy, Bjarne Stroustrop, Linus Torvalds, James Gosling, Richard Stallman, et al.
someone who tries to break into private computer resources
the smallest addressable unit in a computer
For all intents and purposes, a byte is 8 bits in length (a.k.a. octet)
logical byte
an addressable unit other than 8 bits in length
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