Midterm Red Terminology Flashcards
Processor
Central Processing Unit (CPU) Where symbols, characters & Numbers are manipulated
Main Memory
where data and instructions are stored temporarily for quick access during processing
Secondary Storage
Stores data and programs even when computer is off
Input Devices
devices that send instructions to PC - Mouse, KB, touchpad, mic, camera
Output Devices
converts info from computer to something humans understand
e.g.: Monitor, printer, speaker
Communication Devices
provides connections between PC and communication networks
e.g. ethernet, wifi, bluetooth
bit
either 0 or 1
byte
string of 8 bits
word size
how many bits a processor can manipulate in parallel
backwards compatibility
when new software / hardware is designed to be compatible with old
Program Counter
holds address of current instruction
Instruction Register
Holds current instruction
Arithmetic Logic Unit
performs arithmetic and logic (add, sub, mult, div, and, or, not)
Registers
small amount of temporary and fast storage
Control Unit
reads from instruction register and controls processor to execute function
Cache
stores recently used data and instructions
Components of Main Memory
Registers
Cache
RAM
What is a platter
set of disks stacked on top of each other with smooth magnetic coating on both sides
What is RPM
rotations per minute, how fast disk in HDD is spinning
What does an actuator arm do
moves across HDD disk to position read / write heads
What are the types of machines
client / server
What is a client machine
requests and uses services provided by servers
what is a server machine
runs applications and provides it to others
Cloud Computing
share pool of resources:
software, resources, storage
E.G. gmail, google docs, icloud, one drive
Transistor
buildingblock to create computer chips
Moored Law
of transistors that fit on a chip doubles every 18 months
Law of Mass Digital Storage
Amount of digital informations is doubling every year
ASCII
character standard for english
UNicode
character standard for most languages
OS
operating system
manages software and hardware resources of computer
RAID
Redundant array of independent disk
Disk Striping
split data and evenly distributed x times among disks
x times faster
x times more likely to fail
Disk Mirroring
copy data onto multiple disks in case of failure
decreased capacity
increased reliability
Parity
Add a 0 or 1 at end of bits so that sequence has even # of bits
If sequence has odd number, we know its corrupted
Online Backup
instant real time backup
Offline Backup
done at intervals (usually end of day) and stored in another location
backup to cloud or tape
Network
group of computers linked together to share resources
Hub
data received but hub is sent to connected devices
Bridge
One input and output, determines wether to send information
Switch
bridge but with many outputs, decides which output to send on
Router
links networks together
Firewall
hardware / software that prevents outsiders from accessing network
NIC
Network Interfacing Card
ethernet, wifi, bluetooth, nfc
Static website
site does not change unless it is edited
Dynamic Website
site changes based off user activity / queries.
Trade-offs between processors
Efficiency - designed to run a long time with small battery, do not need fan, minimize, transistors (phones / portable devices)
Speed - may need a fan, uses a lot of power, complex w/ possibly lots of transistors (desktops, servers, e.t.c)
Cache details
the lowest level of cache has the smallest storage and is the fastest to access.
As you go higher it has more storage but is a little slower
The most commonly used instructions are stored in the lowest levels first
Multi-core processors
Executes multiple instructions at the same time as each core acts like its own processor
Storage Devices
Static RAM
Dynamic RAM
SSD
HD
USB / SD /Micro SD
DVD / Blu-ray
SRAM
faster than DRAM, used for registers
SSD vs HDD
SSD pros - 10x faster, lasts longer, physically lasts longer
SSD cons - more expensive, data can fade, wears out with a lot of writes
Mainframe
expensive centralized system. One mainframe that is accessed by terminals
Minicomputer
similar to mainframe but smaller
Personal Computer
used by individual to run simple programs
Enterprise computing
links computers networks and applications throughout firm
P2P
every machine in network consumes and provides services at the same time
Metcalfes Law
value of a network grows exponentially with the # of members
DBMS
organizes and stores company data
ISP
internet service provider
Mobile Digital Platform
increasing use of mobile devices accessing internet
BYOD / Consumerization of IT
technology meant for consumer moves into business world
Grid Computing
pool computers to work together to get higher computation power
Virtualization
creation of a virtual software to simulate hardware, OS, storage, network
Load Balancing
evenly distribute workload among many servers
Cloud Computing
leasing / accessing services from another company
SaaS
On Demand Computing
off load peak demand externally (form of cloud computing)
Green Computing
design of computers that minimizes impact on environment
Sanitize
make sure devices are completely wiped before disposal
Autonomic Computing
develop systems that are capable of self-management
P2P systems
SMART - Self Monitoring, Analysis & Reporting Technology
Nanotechnology
using nano structures to build devices
1 transistor = 14 nanometers wide
Quantum Computing
represent data as 2^n states per qu-bit
Open Source Software
Pros:
lower cost, less bugs as everyone can inspect code, flexibility,
transparancy
Cons:
harder to use
compatibility issues
lack of support
HTML -> HTML5
HypertextMarkupLunguage: display info on the web
HTML5 now supports audio & video
Web services
software components that exchange information with each other using web comms
service oriented architecture
use of web services to integrate among different apps and platforms
Software Outsourcing
purchasing / renting customized software package instead of developing own - e.g. SAP
SaaS
software as a service, purchasing and using cloud softwares
Scalability
firms need the ability to expand
Total Cost-of Ownership
Capital expenditure + Operational Expenditure
Capital Expenditure
fixed one time cost to acquire system
Operational Expenditure
ongoing expenses for running software
Direct IT Costs
obvious and direct costs related to IT
(hardware, software, paper, internet costs)
Indirect IT Costs
costs due to lost productivity
(downtime, poorly trained users, etc)
Unmanaged infrastructure
users can install any application and change settings
Locked & Well Managed
users cannot install software or change specific settings
Flat File
storing data in simple files / relational database
Pros & Cons of Flat Files
pros:
simple,easy to understand, easy to search through, good for one person and small data
cons:
lack of security, only one person can access at a time
Database Management System
set up storage structures
update data
process queries
Relational Database
model data as objects
Physical Schema
how data is physically stored
Conceptual Schema
global view of entire DB
External Schema
how data is displayed to a particular user
specific views of data
Hierarchal Database
tree based, based off parent child relationships
Network Database
ER diagram can be a network, entities can have multiple parents
Object Oriented Database
stores type of data and procedures that manipulate data - to store multimedia
Supports inheritance and polymorphism
computer network
2+ PCs connected to share resources
extranet
private network that small subset of users can access
Circuit switching
line is held by circuit until end of communication by both source and desination
Packet Switching
data is broken down into packets, sent to destination, then reassembled
network is only used when sending info
Dijkstra’s algorithm
determines shortest path from source to destination
Node Topology
how are nodes connected to eachother
geographic scale
how big is the network
NFC
near field communication - very close (4cm) e.g. tap pay
PAN
personal area network
bluetooth, 10m
LAN
local area network
within building or floor, ethernet, wifi in house
WAN
wide are network,
usually internet, or network spanning countries (banks, military)
Internet Protocol Suite
standard for networks
Application Layer
defines protocols for apps to exchange data
Transport Layer
