Network Types: LAN, MAN, WAN, WLAN, VPN, Intranet

• A network is a collection of interconnected devices that communicate to share resources, exchange data, and provide services.

Network Types

• LAN connects devices in a limited area, and is typically owned and managed by a single organization.
• MAN connects devices in a metropolitan area, being larger than LANs but smaller than WANs.
• WAN connects devices over a large geographical area, and is typically owned and managed by multiple organizations.
• WLAN connects devices wirelessly using radio waves or infrared signals, often found in homes, offices, and public hotspots.
• VPN is a secure, encrypted network that connects devices over the internet, commonly used for remote access and secure browsing.
• An intranet is a private network within an organization using internet protocols, used for internal communication and collaboration.
• An extranet is a private network connecting an organization with partners, suppliers, or customers, used for B2B transactions and supply chain management.
• The internet is a global network of computers and servers using standardized protocols, accessible to anyone with a connection.
• SAN is a dedicated network for data storage and management, used in data centers and designed for high-speed data transfer.
• CDN is a network of distributed servers for delivering web content, designed to reduce latency and improve performance.

Internet Tools

• Web browsers like Google Chrome and Mozilla Firefox are for accessing and viewing websites.
• Email clients like Gmail and Outlook are for sending and receiving emails.
• FTP clients like FileZilla are for uploading and downloading files.
• Instant messaging apps like WhatsApp and Skype are for real-time communication

Firewalls

• A firewall is a network security system that monitors and controls network traffic based on security rules, acting as a barrier between trusted and untrusted networks.

WWW

• WWW stands for World Wide Web, a system of interlinked hypertext documents accessed via the internet, invented by Tim Berners-Lee in 1989.

Web vs Internet

• The internet is a global network of interconnected computers, while the web is a system of interlinked hypertext documents accessed via the internet.

FTP (File Transfer Protocol)

• FTP is a standard protocol for transferring files between computers over the internet, facilitating file management on remote servers.

Protocol Definition

• In computer networking, a protocol is a set of rules governing data transmission between devices.

Protocols

• HTTP is for transferring web pages and data.
• FTP is for transferring files.
• TCP/IP is for routing data packets across the internet.
• HTTPS is for secure, encrypted communication over the web.

Standardized Protocols

• Standardized protocols govern communication and data exchange between devices and networks.

Data

• Data refers to raw facts, figures, or statistics that have not been processed or analyzed.
• Information is the result of processing, organizing, and interpreting data to make it meaningful.

Qualitative Data

• Qualitative data is descriptive and cannot be measured numerically, categorizing data into groups.
• Nominal Data: Categories with no intrinsic order.
• Ordinal Data: Categories with a meaningful order or ranking.

Quantitative Data

• Quantitative data can be measured and expressed numerically, useful for statistical analysis.
• Discrete Data: Represents counts of items.
• Continuous Data: Represents measurements within a range.

Primary Data

• Primary data is collected directly from a source for a specific purpose.
• Example: A company conducts a survey to understand customer satisfaction.

Secondary Data

• Secondary data was collected for another purpose but is used for a different analysis.
• Example: Using census data to analyze demographic trends in a region.

Structured Data

• Structured data is organized in a predefined format, such as tables, rows, and columns, stored in databases for easy analysis.
• Example: Data stored in an Excel sheet or a relational database.

Unstructured Data

• Unstructured data is not organized in a predefined manner, like text, images, or social media posts, making it harder to analyze.
• Example: Emails, social media content, videos, or photographs.

Semi-structured Data

• Semi-structured data contains elements of both structured and unstructured data, with tags or markers for easier analysis.
• Example: JSON or XML files that contain data in a more organized form but not in tables.

Internal Data

• Internal data is generated and collected within an organization, including data on operations and customer interactions.
• Internal data is often used for decision-making within the organization to monitor performance and improve efficiency.

External Data

• External data comes from outside the organization, including market trends and competitor information, helping organizations understand external factors.
• Example: A business uses external data from market research to inform its product development strategy.

Data Communication

• Data Communication refers to the transmission of data between devices or systems through a communication medium.

Data Transmission

• Data Transmission refers to the process of sending and receiving data over communication channels.

Data Transmission types

• Simplex: Data transmission happens in one direction only.
• Example: A television broadcast, where the signal goes from the broadcast station to the TV receiver.
• Duplex: communication allows for two-way data transmission.
• Full Duplex: Both parties can send and receive data at the same time, for example, a telephone conversation.
• Half Duplex: Data transmission can happen in both directions, but not simultaneously. An example is a two-way radio.
• Half-Duplex: Data transmission is bidirectional, but it happens in one direction at a time.
• Example: Walkie-talkies, where one person speaks while the other listens, and they switch roles afterward.

Master Data

• Master Data refers to the essential core data for business operations, consistently used across the organization.

Examples of Master Data

• Customer Data: Name, address, contact details, and account information.
• Product Data: Product codes, descriptions, prices, categories, and specifications.
• Employee Data: Personal information, job titles, departments, and employee identification numbers.

Characteristics of Information

• Meaningful: Information must have meaning and provide understanding.
• Relevant: Information should be pertinent to the context or problem being addressed.
• Accurate: Information must be correct to be valuable.
• Timely: Information must be available when needed.
• Organized: Information is structured in a way that makes it easy to interpret and use.

Types of Information

• Descriptive Information: Provides details about an entity or event.
• Inferential Information: Derived from analyzing existing data, involving predictions and conclusions.
• Prescriptive Information: Provides guidance or recommendations on actions to take, used in decision-making.
• Operational Information: Relates to the day-to-day activities of an organization.
• Strategic Information: High-level information used for long-term planning and decision-making.

Information vs. Data

• Data: Raw facts and figures without context or meaning.
• Information: Data that has been processed to provide meaning.
• Data alone cannot answer questions or make decisions, while information provides context for decision-making.

Information Processing

• Information Processing: The Conversion of Raw Data into Meaningful Information.

Processing Stages

• Data Collection: Gathering raw data from various sources.
• Data Organization: Sorting and structuring data.
• Data Analysis: Interpreting data to identify patterns and insights.
• Data Presentation: Presenting information in an understandable format.
• Decision-Making: Using information to make informed decisions and develop strategies.