Information Systems Infrastructure PDF

Facoltà di Economia a.a. 2024/2025 Information Systems  Information System Infrasctructure Binary System Hardware Software Network and Communication System  Digital Format Representation of information (e.g. music, documents) and...

Facoltà di Economia a.a. 2024/2025 Information Systems  Information System Infrasctructure Binary System Hardware Software Network and Communication System  Digital Format Representation of information (e.g. music, documents) and any other type of data in a manner that allows processing and utilization by information technologies. The adjective “digital” derives from the English word digit (meaning "number" or "figure"). Information in digital format = Information in numerical format 3  Analog Signal ▪ Analog: A signal is referred to as analog when the values representing it are continuous (infinite). ▪ https://archive.org/details/56kModem56kDialupMo demSound (blackboard 56K_Modem_sound.mp3) – They are comparable to a wave and transmit a wide spectrum of information. They are highly susceptible to interference (or jitter). 4  Digital Signal Digitali: They can only assume two states that are easily distinguishable by a device: - 0 - 1 Advantages: Higher resolution Less interference ON OFF 5  Binary system The electronic system used by computers to represent data and instructions. This system recognizes and processes data and instructions in one of the following forms: - 0 - 1 6  Binary system ▪ bit – The smallest unit of information that a computer can process. ▪ Byte – Composed of 8 bits. It represents the fundamental unit of language in electronic computing; it is the smallest unit of memory capable of holding a character. – 8 bits can differentiate 256 (2⁸) different combinations of "0" and "1". 7  Binary Encoding Schemes ASCII Code that includes conventional characters (letters, numbers, etc.) + mathematical symbols and Greek letters. – ASCII includes 128 characters (7 bits) – Extended ASCII includes 256 characters (8 bits) – with different versions for national characters and 15 different extensions Display Encode Storage 8  Memory Measurements bit: In the binary system, each 0 or 1 is called a bit ("binary digit"). Byte: 8 bit Kilobyte (KB): approximately one thousand bytes (2¹⁰ bytes) Megabyte (MB): approximately one million bytes (2²⁰ bytes) Gigabyte (GB): approximately one billion bytes (2³⁰ bytes) Terabyte (TB): approximately one trillion bytes (2⁴⁰ bytes) Petabyte (PB): approximately one quadrillion bytes (2⁵⁰ bytes) Exabyte (EB): approximately one quintillion bytes (2⁶⁰ bytes) Zettabyte (ZB): approximately one sextillion bytes (2⁷⁰ bytes) Yottabyte (YB): approximately one septillion bytes (2⁸⁰ bytes) 10  Information System Infrasctructure Binary System Hardware Software Network and Communication System Hardware Input devices  Hardware Von Neumann modeled the logical framework for computer operation, which is still valid today, even though it was conceived in the late 1940s and early 1950s. (CPU – Central Processing Unit) Output device Input device Arithmetic Logic Control Unit Unit (ALU) Central Unit Communication Bus Storage Input tech 14  Mouse It is a pointing device Manages a cursor Each mouse is equipped with two components: one for selection (buttons) and one for cursor movement (ball or optical technology) Trackball, Pointing stick, Touch pad  Barcode readers Sections of Code 128 Barcode 1: Quiet zone 2: Start character 3: [FNC1] + data encoding 4: Check character 5: Stop character  QR quick response code Barcode 2.0, interactive and multimedia. To scan a QR Code, specific applications are required. The QR Code compresses information into a small square that mobile devices can quickly scan. Once scanned, the QR Code is translated into usable information, such as a link to a website.  QR - Demo Install "qrencode" Windows: - https://sourceforge.net/projects/qrencode-for- windows/files/QRCodeGui_Win32.zip/download - Test functionality (run cmd.exe from the command prompt), then run the following commands: cd C:\Downloads\QRCodeGui_Win32 qrcode -V OSX: - brew install qrencode - Test functionality (run the commands in a shell): qrencode –V Linux (test functionality as for OSX): - Ubuntu: apt install -y qrencode  QR - Demo Copy the following content into a text editor (e.g., Notepad or another editor) and save it as a file (e.g., file.vcf): BEGIN:VCARDVERSION:2.1 N:Name;Surname;;;FN:Name Surname TITLE:Unicatt EMAIL:[email protected] TEL;TYPE=cell:+39 3XXXXXXXX END:VCARD Run the following command:: Windows: qrcodegui.exe (paste the content above) Linux/OSX: cat file.vcf | qrencode -o «my.png« Open the file "my.png" and scan the QR code with your smartphone's camera. QR - Demo  RFID radio frequency identification Information systems  RFID radio frequency identification RFID (Radio-Frequency Identification) is a technology for the automatic identification and/or storage information related to objects, animals, or people (Automatic Identifying and Data Capture, AIDC). It is based on the capability of special electronic tags, called tags (also known as transponders or electronic and proximity keys), to store data, and on their ability to respond to queries from specific fixed or portable devices called readers (or interrogators) from a distance. This identification occurs via radio frequency, which allows a reader to communicate with and/or update the information stored in the tags it is querying. In fact, despite its name, a reader is not only capable of reading but also writing information.  Output tech Output video Printer Inkjet printer Laser printer Multifunctional printer 3D printer Plotter Output audio 23  input e output: touch screen Functions: Multitouch Pinch to zoom 3D Touch 24  Storage tech Hard Disk and solid State device Floppy disk CD, DVD and blu-ray disk Magnetic tape Memory stick 25 Compare memory storage tech Computer Type 27  HPC- High Performance Computing The most powerful supercomputer in the world is American. The Frontier performs 1.206 trillion operations per second. Ranking of the fastest computers in the world: https://Top500.org 28 Mainframe MIPS (million instructions per second): approximately 18,000 29  Computer (workstation) Allows access to numerous users. Today used in SMEs (Small and Medium-sized Enterprises) or departments. 1960 30 Microcomputer and microcontroller 31 Architecure of a Personal Computer  CENTRAL UNIT CENTRAL UNIT Central memory (RAM) Front-Side-Bus CPU (Processor) Control Unit Registers ALU (CU) CPU CENTRAL UNIT 34  CENTRAL UNIT CPU It operates at a certain clock frequency, which represents one of its performance parameters in terms of processing capability. It can be multicore: Dual core / Quad-core / Eight core... 35  The Moore’s Law The performance of processors and the number of transistors related to them double every 18 months. 36  Central Memory – RAM (Random Access Memory): memory that stores data during processing and the instructions of the program being executed. Volatile. – ROM (Read Only Memory): memory containing fixed and unmodifiable data and instructions; used for programs and instructions automatically loaded at startup (e.g., BIOS). – Cache (L1 and L2): temporarily stores in a fast memory the instructions and data that the microprocessor uses most frequently. – Virtual memory: free disk space that is used to extend the capacity of RAM. – CMOS (Complementary Metal-Oxide Semiconductor): consists of microchips powered by a small battery, which keeps its content constantly updated, consisting of some fundamental information for the correct functioning of the computer.