Basics of Open System Interconnection OSI model

Duration: 10 min

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Module outline

  1. About Course: About the Course
  2. General Aptitude & Reasoning: Number System, Percentage, Ratio and Proportion (Ratios), Average, Profit and Loss, Simple Interest and Compound Interest, Time and Work, Speed Time and Distance, Mixture and Alligation, Data Interpretation, Algebra, Probability, Permutation and Combination, Venn Diagram, HCF LCM, Divisibility Rules, Age Problems, Pipe and Cistern, Partnership, Linear Algebra, Sequence and Series (Series), Statistics, Powers and Exponents (Surds and Indices), Arithmetic, Mensuration and Geometry, Calculus, Trigonometry, Vectors, Speed Mathematics and Basic Mathematics, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Analogy, Series (Number and Letter Series) (Numerical Relations and Reasoning), Puzzle Solving (Puzzles), Syllogisms, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Calendar, Seating Arrangements, Coding Decoding, Blood Relations, Directions (Direction Test), Clock, Analytical Reasoning (Counting Figures Reasoning), Ranking, Order and Sequence, Logical Sequence Of Words, Inequality, Data Sufficiency, Cubes & Dices
  3. Computer Networks & Cybersecurity: 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
  4. Programming, Data Structures & Algorithms: C Fundamentals, Control Flow, Functions, Arrays & Pointers, Storage Classes, Structures & Enums, DMA, Macros, Scoping & File Handling, OOPS with C++, Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing, Algorithm Analysis, Time Complexity Analysis, Sorting Algorithms, Greedy Algorithms, Dynamic Programming, Minimum Spanning Trees, Shortest Path Algos, Advanced Algorithms
  5. AI, Machine Learning, Big Data & Cloud: Emerging Tech Trends, Artificial Intelligence, Big Data Systems, Approaches to AI, Search Algorithms, Knowledge Representation, Cloud Computing
  6. Digital Logic & Computer Organization: Digital Systems & Boolean Basics, Logic Gates & Hardware, Boolean Expression, Boolean Minimization, Combinational Circuit, Sequential Circuits, Number System, Number Representation, Basics of COA, Floating Point Rep, Cache Memory Organization, Input Output Organisation, Pipelining, Instr Formats & Modes, Register Transfer and Microoperations, Control Unit Design, Programming the Basic Computer
  7. TOC & Compiler: Introduction to TOC, Deterministic FA (DFA), Non-Deterministic FA, Regular Expressions, Grammar, Regular Language Properties, Moore & Mealy Machines, Pushdown Automata & CFG, Turing Machines, Complexity Theory, 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
  8. Discrete Mathematics: Set Theory, Relations, Functions, Graph Theory, Group Theory, Propositional and Predicate Logic
  9. Operating System: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Threads & Process Creation, Deadlock, Memory Management, Virtual Memory, Disc Scheduling, File Management, Unix OS, Linux OS, Distributed Systems
  10. Software Engineering: Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Design, Estimation and Metrics, Software Testing, Software Maintenance and Configuration Management, Object Oriented Technology, HTML Basics, JavaScript-Basics, Java, XML
  11. Database Management System: Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, File Organization & Indexing, Relational Algebra, SQL, Relational Calculus, Transaction Management, Concurrency Control, Database Recovery, Data Warehousing & Mining, Enhanced Data Models, NoSQL
  12. Other Recurring CS Topics: Basics of Computer Graphics, 2-D Geometrical Transforms and Viewing, Multimedia
  13. Live Classes: ISRO Live classes
  14. Full Mock Test:
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.

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