Rules of Creating CIDR Block

Duration: 4 min

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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.

This lecture segment introduces the three fundamental rules for creating a valid CIDR block (network). The instructor presents a slide titled “Rules for Creating CIDR Block (Network)” listing: (1) all IP addresses in the block must be contiguous; (2) the block size, i.e., total number of IP addresses contained in the block, must be representable as a power of 2 (e.g., 2^1, 2^2, 2^3, 2^4, 2^5); and (3) the first IP address of the block must be divisible by the size of the block. The instructor then works through an example using the IP address 167.92.48.32, writing it on the board and performing related calculations involving values such as 256 and binary representations (e.g., “10000” and “11111”) to illustrate the divisibility rule. A division calculation (2300 / 106) is also shown on the right side of the board, though its exact role in the example is not fully clear from the sampled screenshots. The segment emphasizes how to verify whether a given IP address can serve as the base of a CIDR block by checking contiguity, power-of-2 size, and divisibility.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The slide “Rules for Creating CIDR Block (Network)” lists three bullets: IP addresses must be contiguous, block size must be a power of 2 (shown as “2^1, 2^2, 2^3, 2^4, 2^5”), and the first IP address must be divisible by the block size. The instructor writes “167 92 48 32” on the right, adds small figures “6” and “3” beneath the last octet, and begins a bracketed column with “17” over “17,” indicating the start of a worked example next to the rules.

  2. 2:00 – 4:26 02:00-04:26

    The instructor continues the example with 167.92.48.32, writing “256” and “257” on the board and drawing a binary representation with 16 host bits circled. A division calculation (2300 / 106) appears on the right side, and the instructor points to binary digits “10000” and “11111.” The final frame shows the three rules again with “256” and “167.92.48” on the right, reinforcing that block size must be a power of 2 and the base address must be divisible by it.

The core teaching point is that a valid CIDR block must satisfy three conditions: contiguity of addresses, power-of-2 size, and divisibility of the base address by the block size. The instructor uses 167.92.48.32 as a concrete example, writing it on the board and performing calculations involving 256 (a power of 2) and binary representations to demonstrate how the divisibility rule works. The presence of “10000” and “11111” suggests the instructor is showing how host bits or block boundaries align in binary. The division (2300 / 106) is visible but its exact purpose in the example is not fully clear from the sampled screenshots; it may relate to a different aspect of CIDR calculation or be part of an intermediate step. The segment is focused on rule application rather than deriving the rules from first principles.

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