Cyclic Redundancy Check Part-2

Duration: 4 min

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Inside: a video lesson and guided study material.

Module outline

  1. Paper 1 | Reasoning Test: Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Data Sufficiency, Syllogisms, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Seating Arrangements, Blood Relations, Puzzle Solving (Puzzles), Venn Diagram, Analogy, Ranking, Order and Sequence, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Selection Decision Table (Decision Making), Logical Sequence Of Words, Cubes & Dices, Analytical Reasoning (Counting Figures Reasoning), Calendar, Alphabet and Word Tests, Numerical Reasoning, Number System, Averages, Mixtures and Alligation, Percentages, Series Completion, Analogy and Classification, Patterns in Two-Dimensional Figures, Coding and Decoding, Mathematical Operations, Direction Sense, Algebra, Logical Deduction and Induction, Syllogisms and Venn Diagrams, Critical Reasoning, Order, Ranking and Sequence, Reading Comprehension, Profit, Loss and Discount, Constraint Puzzles, Speed, Time and Distance, Traverse Surveying, Ratio and Proportion, Time and Work, Mensuration, Permutations and Combinations, Clocks and Calendars, Data Interpretation, Assembling and Grouping of Shapes, Transformation of Shapes, Three-Dimensional Patterns and Visualization, Cubes and Dice, Vocabulary, Blood Relations, Data Sufficiency
  2. Paper 1 | Numerical Analysis: Number System, HCF LCM, Percentage, Ratio and Proportion (Ratios), Average, Sequence and Series (Series), Powers and Exponents (Surds and Indices), Algebra, Statistics, Data Interpretation, Mental Ability, Arithmetic, Logarithm, Profit and Loss, Simple Interest and Compound Interest, Speed Time and Distance, Mixture and Alligation, Mensuration and Geometry, Permutation and Combination, Probability, Sequences and Series, Powers, Surds and Logarithms, Subject-Verb Agreement, Sentence Completion, Geometry, Sentence Structure and Correction, Data Sufficiency, Trigonometry, Measurement and Quantity Take-Off, Signal Space and Optimum Detection, Probability, Statistics, Algebra, Time and Work, Speed, Time and Distance, Data Interpretation, Graph Theory, Combinatorics
  3. Paper 1 | General Knowledge: State Wise GK, History, Geography, GK- Current Affairs, Static General Knowledge, Polity, Indian Economy
  4. Paper 1 | DBMS: Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, File Organization & Indexing, Relational Algebra, SQL, Transaction Management, Concurrency Control, Relational Calculus, Database Security & Authorization, Database Recovery
  5. Paper 1 | Data Communication & Network: 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, Network Security, Security in Mobile and Wireless Computing, Input Output Organisation, File Management, Hardware Basics, Terms & Abbreviations, Protocols & Services, Network Access Technologies, Cyber Safety and Security, Basics of COA
  6. Paper 2 | System Analysis & Design: Fundamentals of Systems and Information Systems, SDLC and Development Approaches, Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Documentation and Software Requirements Specification (SRS), SDD and Quality Assurance, Software Design, Estimation and Metrics, Software Testing, Software Maintenance and Configuration Management, Security, Risk Management & Maintenance, extras
  7. Paper 2 | Programming Language (Java): Java Fundamentals, OOPS with Java, Array, String, IO & References, Generic & Collections, Multithreading, Java, Miscellaneous, Control Flow, OOPS with C++, Stack, C Fundamentals, Arrays & Pointers, Object Oriented Technology, Control Flow & Looping, Introduction to Python
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

This lecture segment introduces Cyclic Redundancy Check (CRC) as an error detection method using cyclic codes. The instructor explains the encoding process where a k-bit dataword is augmented with n-k zeros and divided by a generator polynomial using modulo-2 division. The remainder, consisting of n-k bits, is appended to the original dataword to form an n-bit codeword. The decoder receives this codeword and processes it through a checker identical to the generator, producing an n-k bit syndrome. If all syndrome bits are zero, the dataword is accepted; otherwise, it indicates errors and the codeword is discarded.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The lecture opens with a slide titled "Cyclic Redundancy Check" displaying block diagrams for Sender Encoder and Receiver Decoder. The instructor uses a pen to point at the dataword section showing input bits d3 d2 d1 d0 being processed by a generator to produce remainder bits r2 r1 r0. Bullet points explain augmenting the dataword with zeros and performing modulo-2 division to create a codeword. The text on screen identifies key components: Generator, Checker, and Decision logic. The presenter highlights that the quotient is discarded while only the remainder forms part of the final transmission, establishing the fundamental encoding mechanism.

  2. 2:00 – 3:49 02:00-03:49

    The instructor focuses on the decoding process and syndrome calculation. He circles the divisor size formula "n - k + 1" on screen and writes notes like "n-k=3" to illustrate the remainder length. The slide explains that the decoder receives a possibly corrupted codeword, feeding all n bits to a checker which is a replica of the generator. The remainder produced becomes an n-k bit syndrome fed to decision logic analyzer. If syndrome bits are all 0s, the leftmost k bits of codeword are accepted as error-free dataword; otherwise, it is discarded. This completes the CRC cycle from encoding through error detection.

The video demonstrates a complete CRC workflow starting with dataword augmentation and modulo-2 division encoding, followed by syndrome-based error detection at the receiver. Key technical elements include the generator polynomial for division, the n-k bit remainder appended to form codewords, and the checker circuit producing syndromes for validation. The instructor emphasizes that quotient is discarded during encoding while remainder becomes parity bits, and at decoding, zero syndromes indicate successful transmission. The visual progression moves from sender-side bit processing to receiver-side syndrome analysis, showing how cyclic codes enable reliable data transmission through systematic error checking mechanisms.

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