ExamOneBrainScapeData Flashcards
Open computing
Open source software. Standards allowed heterogeneous systems to communicate with each other and exchange data. This was critical to the development of the World Wide Web - e-markets - e-commerce - and inter-company integration.
Distributed computing
A distributed system is a software system in which components located on networked computers communicate and coordinate their actions by passing messages. The components interact with each other in order to achieve a common goal.
Centralized computing
Centralized computing is computing done at a central location - using terminals that are attached to a central computer. The computer itself may control all the peripherals directly (if they are physically connected to the central computer) - or they may be attached via a terminal server.
Virtualization and logical computing
Virtual - existing or result in essence or effect though not in actual fact form or name. Created - simulated - or carried on by means of a comp or comp net. Making physical thing look like multiple physical things - segmenting it into multiple
What is a protocol
Common ground rules of communication between computers - I/O devices - and many software programs. Exp: HTTP: between Web servers and Web browsers - TCP/IP: between computers on the Internet and local area networks
What is a standard
Created to ensure universal compatibility of data formats and protocols. May be created by committee or may become a de facto standard through popular use. Exp: Java - SQL - C - JavaScript - MPEG-2 - JPEG - PNG - ASCII - Unicode - EBCDIC - MPEG-2 - MPEG-4 - MP3 - DVD-ROM
What is an operating system - and what are the major/popular operating systems
the software that supports a computer’s basic functions - such as scheduling tasks - executing applications - and controlling peripherals. Windows - Mac - Linux.
What is a programming language
A programming language is a formal constructed language designed to communicate instructions to a machine - particularly a computer. Programming languages can be used to create programs to control the behavior of a machine or to express algorithms.
What is ARPANET
Started in 1969 - early packet switching network and first network to use protocol suite TCP/IP. Both became the technical foundation of the internet (Advanced Research Projects Agency Network.)
What is a system and its components
A system is a collection of components linked together and organized in such a way as to be recognizable as a single unit. Ie your own network in your home. Linked components of a system also define a boundary for the system. The environment is anything outside of the system
Client-server model and the n-tier architecture
A program on a client computer requests services from a program on a server computer. Ie email. N-tier arch - Further separation of applications and processing.
Intranet vs. Internet
Internet is wide network of computers and is open for all. Users are unlimited - etc. Intranet is also a network of computers designed for a specific restricted group of users - restricted traffic - etc.
Cloud computing models
SaaS - PaaS - IaaS
What is HTTP
The Hypertext Transfer Protocol (HTTP) is an application protocol for distributed - collaborative - hypermedia information systems. HTTP is the foundation of data communication for the World Wide Web.
What is HTML
Hypertext Markup Language
What a ?base? numbering system is
The number of representations of a number in a system.
Binary
Base 2 system of 1’s and 0’s
Decimal
base 10 system of 0-9
Hexadecimal
base 16 system of 0-9 & A - B - C - D - E - F
Range of possible values
Maxes based on the base
Alphanumeric
Characters: b T - Number digits: 7 9 - Punctuation marks: ! ; Special-purpose characters: $ &
numeric
Used for mathematical manipulation. Add - subtract - multiply - divide. Types: Integer (whole number) - Real (contains a decimal point).
Alphanumeric vs numeric
Both entered as ordinary characters. Computer converts into numbers for calculation. Examples: Variables declared as numbers by the programmer (Salary$ in BASIC). Treated as characters if processed as text. Examples: Phone numbers - ZIP codes
Collating sequence
Alphabetic sorting if software handles mixed upper- and lowercase codes. In ASCII - numbers collate first; in EBCDIC - last. ASCII collating sequence for string of characters.
Coding tables: why are they needed - how do they work
sets a standard for collating for a particular table - ie ascii etc.
Unsigned integers
Unsigned can hold a larger positive value - and no negative value. Unsigned uses the leading bit as a part of the value.
Signed integers
Signed version uses the left-most-bit to identify if the number is positive or negative. signed integers can hold both positive and negative numbers.
Binary-coded decimal
a system for coding a number in which each digit of a decimal number is represented individually by its binary equivalent.
One?s complement
The ones’ complement of a binary number is defined as the value obtained by inverting all the bits in the binary representation of the number (swapping 0s for 1s and vice versa). The ones’ complement of the number then behaves like the negative of the original number in some arithmetic operations.
Two?s complement
Two’s complement is the way every computer I know of chooses to represent integers. To get the two’s complement negative notation of an integer - you write out the number in binary. You then invert the digits - and add one to the result.
Instructions:
Op Code represented by a single digit & Operand represented by 2 digits following the op code. Data or address of data to be manipulated. Cyle is to Fetch & Execute
Load
5xx or LOAD
Store
3xx or STORE
Add
1xx or ADD
Subtract
2xx or SUB
Input
901 or INPUT
Output
902 or OUTPUT
Coffee Break
000 or HALT OR COB
Branch ? unconditional
6xx or JUMP
Branch on Zero
7xx or BRANCH ON 0
Branch on Positive
8xx or BRANCH ON +
How to write a LMC program to accomplish a particular task
fetch - execute using the instruction codes allowed.
