Chapter 3: Computer and Network Architectures

Computer

one that computes; specifically a programmable usually electronic device that can story, retrieve, process data

Supercomputer

mainframe enterprise level

Server

robust in terms of speed and memory

Microcomputer

systems based on a single-chip microprocessors

Minicomputer

are a class of multer-user computers that lie in the middle range of the computing spectrum

Moore’s Law

everything from speed to size to cost per unit of power doubles every 18 months

Computer Hardware

• CPU

• RAM

• Auxiliary Storage

• Input/Output Devices

Central Processing Unit (CPU)

where the computer chips reside and is related to data processing speed (speed measured in Hertz = 1 CPU clock cycle per second)

Random Access Memory (RAM)

the working memory that is lost when the computer is turned off

Auxiliary Storage

active storage is where data is stored that is needed continuously. Archival storage can refer to tape, hard disks, optical drives, or cloud

Computer Software

programs that instruct the hardware what to do

• operating systems

• APIs

Operating Systems

provide a standardized way for software programs to perform tasks

Application Programming Interfaces (APIs)

allow applications to communicate and exchange data over networks

A (100-90)

B+ (89-80)

C+ (79-70)

D+ (69-60)

F (<60)

If grade <= 100 & grade >= 90 then final-grade = A, else

If grade <= 89 & grade >= 80 then final-grade = B+, else

If grade <= 79 & grade >= 70 then final-grade = C+, else

If grade <= 69 & grade >= 60 then final-grade = D+, else

final-grade = F

Open-Source Software

software with source code that is free and shareable (i.e., Linux, Apache, Mozilla, OpenOffice, etc.)

Database

a collection of data that is organized allowing the end user to extract the data; data can be various elements that are different types and sizes

Telecommunications Protocol / Internet Protocol stack (TCP/IP)

communications standard for global network-of-networks

Advanced Research Projects Agency Network (ARPANET)

began late 1960s as a network capable of tying together universities and research organizations securely

World Wide Web (WWW)

operates on top of the internet and was created by Tim Berners-Lee in 1989 and introduced the web browser

Hypertext Markup Language (HTML)

web pages are written using this; the format of data

Interoperability

ability to communicate with other devices

Hypertext Protocol (HTTP)

for the exchange of data

Domain Name Service (DNS)

Dynamic Host Configuration Protocol (DHCP)

Node

each machine with an address on a network

Internet Service Provider (ISP)

how computers connect to the internet

Components Needed for a Connection

IP address - unique address assigned to network

Subnet Mask - division of network

IP Version 4 (IPv4)

has a 32-bit address length

IP version 6 (IPv6)

has a 128-bit address length

Uniform Resource Locator (URL)

the address we use to locate a server on the internet

RESTful (Representational State Transfer) Architecture

for handling “state'“, internet clients and servers respond to each other in asynchronous manner, need a means for maintaining “state” that does not require continuous connection

Open Systems Interconnection (OSI) Model

a conceptual model created in 1984 to help understand network architectures. it divides computer-to-computer communication into seven layers known as the OSI stack