ClassLess Interdomain Routing - CIDR With Example

Duration: 4 min

This video lesson is available to enrolled students.

Return to /learn/RPSC-PROGRAMMER/paper-1-data-communication-network/net-layer-ip-addressing/cidr-vlsm/asset-classless-interdomain-routing-cidr-with-example after enrolling

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 teaches how to determine the number of addresses, first address, and last address for a CIDR block using an address mask. The instructor works through the example 167.199.170.82/27, showing its binary form 10100111 11000111 10101010 01010010. The mask is formed by setting the 27 leftmost bits to 1 and the remaining 5 bits to 0. The number of addresses is calculated as N = NOT(mask) + 1, which equals 2^5 = 32. The first address is found by ANDing the given address with the mask, yielding 167.199.170.64. The last address is found by ORing the given address with NOT(mask), yielding 167.199.170.95. A summary slide titled “Address Mask” defines the mask as a 32-bit number with n leftmost bits set to 1 and the rest 0, and lists the three bitwise operations NOT, AND, and OR used to compute block properties.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The slide presents the question “Find the Number of addresses, first and last address of the CIDR block to which” with “Address: 167.199.170.82/27 (10100111 11000111 10101010 01010010) belongs to.” The instructor circles the address line and underlines binary octets, isolating the final group “01010010.” He then writes “2^5 = 32” on the whiteboard, indicating that with a /27 prefix there are 5 host bits and therefore 32 addresses in the block.

  2. 2:00 – 4:15 02:00-04:15

    A second slide states “The mask by setting 27 leftmost bits to 1 and 5 rightmost bits to 0 in dotted-decimal notation is:” and “Number of addresses in the block: N = NOT (mask) + 1 =”, with “NOT” circled in red. The instructor sketches tally marks and five circles representing the zero bits. Later slides show “First address: First = (address) AND (mask) =” and “Last address: Last = (address) OR (NOT mask) =”, with binary rows for the AND and OR operations. The computed first address 167.199.170.64 and last address 167.199.170.95 appear on screen. A final “Address Mask” slide defines the mask as a 32-bit number with n leftmost bits set to 1 and lists N = NOT(mask) + 1, first address = (any address in block) AND mask, and last address = (any address in block) OR NOT(mask).

The lesson centers on CIDR address-mask arithmetic. The key rule is that a /n prefix creates a mask with n leading 1-bits and (32-n) trailing 0-bits. From this mask, three bitwise formulas give block properties: N = NOT(mask) + 1 for the number of addresses, first address = address AND mask, and last address = address OR NOT(mask). In the worked example 167.199.170.82/27, the five trailing zero bits give 2^5 = 32 addresses. ANDing with the mask clears host bits to produce the first address 167.199.170.64, while ORing with NOT(mask) sets host bits to 1 to produce the last address 167.199.170.95. The progression moves from identifying the prefix length, to constructing the mask, to applying NOT/AND/OR operations, and finally to a summary slide that generalizes the method.

Loading lesson…