Basics of Open System Interconnection OSI model

Duration: 10 min

This video lesson is available to enrolled students.

Return to /learn/NIACL-AO-IT-SPECIALIST/data-communication-networking-it-specialist/introduction-to-cn/osi-model-layers/asset-basics-of-open-system-interconnection-osi-model after enrolling

Inside: a video lesson and guided study material.

Module outline

  1. Quantitative Aptitude: Ratio and Proportion (Ratios), Data Interpretation, Mixture and Alligation, Permutation and Combination, Number System, Sequence and Series (Series), Speed Time and Distance, Speed Mathematics and Basic Mathematics, Algebra, Percentage, Profit and Loss, Simple Interest and Compound Interest, Powers and Exponents (Surds and Indices), Time and Work, Mensuration and Geometry, Partnership
  2. Reasoning Ability: Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Data Sufficiency, Seating Arrangements, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Directions (Direction Test), Ranking, Order and Sequence, Syllogisms, Blood Relations, Puzzle Solving (Puzzles), Inequality, Machine Input-Output
  3. English Language: Vocabulary, Noun, Subject Verb Agreement (Verb Noun Agreement), Adjectives, Tenses, Comprehension / Reading Comprehension / Unseen Passages (Critical Reasoning) (Paragraph Questions), Cloze Test (Cloze Passage), Sentence Correction (Error Correction), Sentence Completion (Fill in the blanks), Sentence Re-arrangements (Para Jumbles) (Narrative Sequencing), Sentence Construction, Pronoun, Preposition, Conjunction, Adverb, Verb, Modals, Articles, Determiner, Interjection
  4. General Awareness: Evolution of Indian Banking (Banking & Financial Awareness), GK- Current Affairs, Static General Knowledge, Indian Economy
  5. C Concepts + MCQs (IT Specialist): C Programming by Yash Sir, C Language Core
  6. Java (IT Specialist): Java
  7. Python (IT Specialist): Python for Placements by Yash Sir, Python Basics
  8. OOPs (IT Specialist): Object Oriented Programming (OOPS)
  9. DBMS (IT Specialist): Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, File Organization & Indexing, Relational Algebra, Relational Calculus, Transaction Management, Concurrency Control, Database Recovery, ORDBMS, Database Security & Authorization, Query Processing & Optimization, Enhanced Data Models, Data Warehousing & Mining, Big Data Systems, NoSQL
  10. SQL (IT Specialist): SQL
  11. Software Engineering (IT Specialist): Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Design, Estimation and Metrics, Software Testing, Software Maintenance and Configuration Management
  12. Data Structure (IT Specialist): Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing
  13. Operating System (IT Specialist): Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Deadlock, Threads & Process Creation, Memory Management, Virtual Memory, Disc Scheduling, File Management, Windows OS, Linux OS, Security, Distributed Systems, Virtual Machines
  14. Compiler Design (IT Specialist): Intro to Compilers, Lexical Analysis, Grammar & CFG, Syntax Analysis: Top-Down, Syntax Analysis: Bottom-Up, Semantic Analysis & SDT, Intermediate Code Gen, Code Optimization, Run Time Environment
  15. Computer Architecture (IT Specialist): Basics of COA, Floating Point Rep, Cache Memory Organization, Input Output Organisation, Pipelining, Instr Formats & Modes, Control Unit Design, Register Transfer and Microoperations, Multiprocessors, Programming the Basic Computer
  16. Data Communication & Networking (IT Specialist): Introduction to CN, Data Communication, DLL: Access Control, DLL: Flow Control, DLL: Error Control, DLL: Framing, Data Link Layer - Ethernet, Net Layer: IPv4 & Proto, Net Layer: IP Addressing, Net Layer:Routing Protocol, Transport Layer Services, TL: Congestion & UDP, Application Layer, Hardware basics, Network Security
  17. Descriptive Test (Main Exam): English Writing Ability
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

The lecture introduces the OSI model as a conceptual framework proposed by ISO to enable communication between heterogeneous systems. It emphasizes that the OSI model is not a protocol but an architectural reference, consisting of seven layers: Application, Presentation, Session, Transport, Network, Data Link, and Physical. The instructor uses diagrams to show encapsulation, where headers (AH, PH, SH, TH, NH, DH) are added to data as it moves down the stack, ending in bits on the media. A protocol table maps real-world protocols like TCP, UDP, IP, ICMP, ARP, and RARP to their respective layers, contrasting the OSI model as 'Directive Principles' with actual protocols as the 'Constitution'.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The slide titled 'Network Models' introduces the OSI model, noting that ISO proposed it to allow two systems to communicate regardless of architecture. A seven-layer diagram is shown alongside a staircase encapsulation model with headers AH, PH, SH, TH, NH, and DH. The instructor enters the frame to begin explaining the layered task concept.

  2. 2:00 – 5:00 02:00-05:00

    The lecture clarifies that an open system allows different systems to communicate without changing underlying hardware or software logic. A key transition occurs where the instructor states, 'The OSI model is not a protocol,' but rather a model for designing flexible and robust network architectures. A protocol table appears, mapping TCP/UDP to Transport and IP/ICMP to Network.

  3. 5:00 – 10:00 05:00-10:00

    The instructor elaborates on the seven separate but related layers, using a stylus to point at the encapsulation diagram. The diagrams are labeled 'Directive Principles' for the OSI stack and 'Constitution' for the protocol table. The slide text emphasizes that each layer defines a part of the process of moving information across a network.

  4. 10:00 – 10:02 10:00-10:02

    The final view shows the complete 'Constitution' chart mapping additional protocols like SNMP, NTP, HTTP, and FTP to their layers. The summary reinforces that the OSI model provides a standardized framework for understanding how data is encapsulated and transmitted through different system architectures.

The lecture provides a foundational overview of the OSI model, focusing on its role as an architectural reference rather than a specific protocol. Key concepts include the seven-layer hierarchy and the process of encapsulation, where data is wrapped with headers at each level. The instructor uses a metaphor comparing the OSI model to 'Directive Principles' and actual protocols like TCP/IP to the 'Constitution,' highlighting that while the model provides a standard for design, real-world implementations vary. This distinction is crucial for students to understand that the OSI model is a tool for analysis and design, ensuring interoperability across different hardware and software environments.

Loading lesson…