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OSI Model

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The OSI (Open Systems Interconnection) model is a conceptual framework or guidelines used to understand and describe different networking protocols interacting within a computer network, developed by the International Organization for Standardization (ISO) in 1970s to create a standardized or structured way of discussing and understanding the complexities of network communication. The OSI model divides network communication into seven distinct layers, each one is responsible for specific tasks, organized in a hierarchical manner, with each layer building upon the services provided by the layer below it, ensures that data moves from its point of origin to its destination efficiently and accurately. The block diagram of seven layers are as follows: Physical Layer (Layer 1): Physical layer lies at the base of the OSI model, focusing on the transmission of raw data bits through physical mediums such as cables, fibers, or wireless connections. It defines attributes like voltage levels, dat

Network Protocols

IN THIS ARTICLE (a) What is Network Protocol? (b) Examples of Protocols (c) Layers of TCP/IP Model (d) Explanations on different protocols A computer network's data transmission, reception, and processing are governed by a set of rules and standards called as network protocols . These protocols define structure and format of data packets, the methods for error detection and correction, and the procedures for establishing and terminating connections between devices on a network. Network protocols are crucial for facilitating communication between various systems and equipment, such as PCs, servers, routers, switches, and more, within a network. They ensure that data can be sent and received accurately and reliably, even in complex and diverse network environments. Depending on different purposes and network types, requirements of the network, software and application running over the network, there many protocols designed, few of them as below: (1) Transmission Control Protocol (TCP

Network an introduction

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IN THIS ARTICLE (a) What is Network? (b) Types of Network (c) What is Network Connection? (d) Types of Network Connections (e) What is Network Protocol? (f) What is Network Packets? (g) What is Network Topology? (h) Types of Network Topology A Network is a group of  two or more interconnected devices for information or resource sharing and communication. The interconnected devices can be laptop, PC, server, router, switches, printer, smart phone and tablet etc. Types of Network (A) LAN (Local Area Network): It is used to cover a limited or small area like home, office and campus. (B) MAN ( Metropolitan Area Network): It covers a single geographical area and within that area connects different LANs from different locations like a city or large campus. (C) WAN (Wide Area Network): It is used to cover larger geographical area and connects different LANs from different locations like cities, regions and countries. For example: Internet Connections In networking, " connections "

Key differences between Information Security and Cyber Security

Information security has a more comprehensive scope that covers both physical and digital aspects of information protection while Cybersecurity is a specialized subset that focuses solely on digital data and assets in the context of online threats. Both are crucial elements of a company's overall security strategy, working together to reduce potential threats and provide all-encompassing security. Key differences between the two areas are as below: 1. Protection Boundaries Information security covers a wider range of issues pertaining to protecting all forms of sensitive information. This comprises intellectual property, physical documents, digital data, and staff expertise. No matter the medium in which the information is stored (physical or digital), information security attempts to safeguard its availability, confidentiality, and integrity while Cyber security a  subcategory of information security, is concerned with precisely defending digital assets and information against onl

Cyber Security

" Threat  is potential cause of an unwanted incident, which may result in harm to a system or organization"  (ISO IEC 27000 : 2017 Clause 2.83) " Attack  is an attempt to destroy, expose, alter, disable, steal or gain unauthorized access to or make unauthorized use of an asset "  (ISO IEC 27000 : 2017 Clause 2.3) The Cyber Security is a multidisciplinary field. The primary objective of cybersecurity is to defend digital systems, networks, and data against threats, vulnerabilities, and attacks. It is essential in today's interconnected world, where reliance on technology and the internet has made people, organizations, and governments vulnerable to a number of cyberthreats. Cyberthreats: These are criminals or hacker-initiated online behaviors or acts that target weaknesses in computer networks, systems, and data. Malware (such as viruses and ransomware), phishing scams, denial-of-service (DoS) attacks, data breaches, and insider threats are examples of common c

Information Security

" Information is meaningful and useful data which can be processed, refined, analyzed, structured, relevant to the criteria, verifiable and documented as needed" "Information is an asset , has value for any organization like other important assets."  " Information System  can be applications, services, information technology assets, or other information handling components"  (ISO IEC 27000 : 2017 Clause 2.39) " Threat is potential cause of an unwanted incident, which may result in harm to a system or organization"  (ISO IEC 27000 : 2017 Clause 2.83) " Attack  is an attempt to destroy, expose, alter, disable, steal or gain unauthorized access to or make unauthorized use of an asset "  (ISO IEC 27000 : 2017 Clause 2.3) " Information security is preservation of confidentiality, integrity and availability of information " (ISO IEC 27000 : 2017 Clause 2.33) Information security or InfoSec , is a broad discipline deals with prot

Aliasing in SQL

Giving a table or column a temporary name or alias in a SQL query is known as aliasing. In the context of a given query, it makes it possible to refer to a different table or column, hence  enables to simplify complex queries, enhance readability, and resolve naming conflicts in a query. Table Aliasing: When utilizing table aliases, give a table in the query a temporary name. This is especially helpful when refers to a table with a long or complicated name or if need to link several tables. Table aliasing's fundamental syntax is as follows: SELECT alias.column_name FROM table_name AS alias; Consider the following scenario: Extract the names of the employees along with the names

Installation of SQL Server Management Studio (SSMS) & SQL Server

Planning: 1.  Understand SQL Server basics 2.  Understand SQL Server Architecture 3.    Install SSMS 4.   Install SQL Server 5.   Connect SSMS to SQL Server   6. Attach Database to SSMS Follow these steps to install SQL Server Management Studio (SSMS): 1.  Navigate to the Microsoft Download Centre page. 2.  Choose the correct version of "SQL Server Management Studio" for your SQL Server installation by performing a search for it. 3.  To start the download, click the Download button. 4.  Run the setup program to begin the installation process after the download is finished. 5.  Select the "SSMS" feature and any additional features you wish to install in the Installation Wizard. 6.  Click "Install" to launch the installation procedure after selecting the installation location. 7.  Hold off until the installation is finished. Determining how long it will take depends on your system. 8.  Use the Windows Start menu to run SSMS after the installation is complete

SQL Server Architecture

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The architecture of SQL Server is based on the client-server model, where clients send requests to the server for accessing or modifying data stored in the database. The SQL Server architecture consists of three main components: the client, the SQL Server instance, and the operating system. Here is a brief explanation of each main component: Client: This component is responsible for sending requests to the SQL Server instance and receiving the results. The client can be any application or tool that can connect to SQL Server, such as SQL Server Management Studio, Visual Studio, .NET applications, web applications, desktop applications, and mobile apps. Client communicates with the SQL Server instance using a network protocol such as TCP/IP. SQL Server Instance: This component is the core of the SQL Server architecture. It includes the SQL Engine, which is responsible for processing SQL queries, and the storage engine, which is responsible for managi

SQL Server an Introduction

The relational database management system (RDBMS) known as SQL Server was developed by Microsoft. Data in relational database format is stored, managed, and retrieved using the SQL language (Structured Query Language). SQL Server supports the relational database management language SQL.  A type of database management system (DBMS) used to manage and organise data is called a relational database management system, or RDBMS for short. The relational database paradigm was first proposed by E.F. Codd in 1970. It is predicated on the notion of a table or relation that contains data in rows and columns. Every table in an RDBMS contains a connected set of data that is organised into relations or tables. Each row in a table represents a distinct record, and each column represents a distinct piece of data or attribute. The relationships between tables are defined through the usage of keys, such as primary keys and foreign keys, which are used to connect records in different tables. Compared to

Unpivot using SQL

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When converting columns into rows in SQL, unpivoting is used, effectively converting wide format (i.e., data with many columns) into long format (i.e., data with fewer columns and more rows). The process of pivoting, which includes turning rows into columns, is the opposite of this.   Here is the syntax of Unpivot in SQL: SELECT [column1], [column2], [column3] FROM (   SELECT [id], [column1], [column2], [column3]   FROM [table_name] ) AS [source_table] UNPIVOT (   [value] FOR [column_name] IN ([column1], [column2], [column3]) ) AS [unpivot_table]; In this syntax: [column1] , [column2] , and [column3] are the columns you want to unpivot. [table_name] is the name of the table containing the data you want to unpivot. [id] is a column that uniquely identifies each row in the table. [value] is the name of the column that will contain the values that were previously in the unpivoted columns. [column_name] is the name of the column that will contain the original column names. [unpivot_ta