CIDR Practice Question_
Duration: 3 min
This video lesson is available to enrolled students.
Inside: a video lesson and guided study material.
Module outline
- About Course: BTSC About Course
- Basics of Computer Science: Basics of COA, Number System, Number Representation
- Operating System: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Threads & Process Creation, Deadlock, Memory Management, Virtual Memory
- Data Structures & Algorithms: Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing, Algorithm Analysis, Time Complexity Analysis, Sorting Algorithms
- Database Management Systems(DBMS): Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Relational Algebra, SQL, Transaction Management, Concurrency Control, Database Recovery
- Networking and Internet: Introduction to CN, Data Communication, Net Layer: IPv4 & Proto, Net Layer: IP Addressing, Application Layer, Hardware Basics, Network Access Technologies, Network Security
- Cyber Security Basics: Cyber Threats and Malware Attacks, Role of Internet and Web Services, Electronic Data Interchange and E-Commerce, Cyber Safety and Security
- C Programming (Programming Fundamentals): C Fundamentals, Control Flow, Functions, Arrays & Pointers, Storage Classes, Structures & Enums, DMA, Macros, Scoping & File Handling
- C++, OOPs & Java (Programming Fundamentals): Java, OOPS with C++
- Python (Programming Fundamentals): Introduction to Python, Tokens, Variables, Data Types, I/O, Operators & Expressions, Control Flow & Looping, Collections & Strings, Functions & Modules
- Web Development Basics: Internet Fundamentals, Web Design & Development, Protocols & Services, Web Publishing & Hosting, Server Side & Security, Emerging Technologies, JavaScript-Basics, HTML Basics
- Software Engineering: Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Design, Estimation and Metrics, Software Testing
- Software and Hardware Tools: MS Office Applications, Unix OS, Linux OS
- Emerging Trends. AI & Social Ethics: Artificial Intelligence, Emerging Tech Trends, Society, Law & Ethics
- Full Mock Test:
AI summary & chapters
AI Summary
An AI-generated summary of this video lecture.
The lecture focuses on validating and representing a specific range of IP addresses as a Classless Inter-Domain Routing (CIDR) block. The instructor presents a problem involving the range 150.10.20.64 to 150.10.20.127 and systematically applies three specific rules to determine validity. He calculates the total number of addresses, verifies it is a power of two, and checks the divisibility of the starting address. Finally, he derives the subnet mask length by calculating the necessary host bits to complete the CIDR notation.
Chapters
0:00 – 2:00 00:00-02:00
The instructor introduces the problem statement on screen: 'Consider a block of IP Addresses ranging from 150.10.20.64 to 150.10.20.127'. He lists three rules for CIDR blocks: contiguity, power-of-two size, and divisibility of the first address. He calculates the block size using the formula 127 - 64 + 1, resulting in 64. He lists powers of 2 (2, 4, 8, 16, 32, 64) to confirm 64 is valid. He then checks the third rule by dividing the first address (64) by the block size (64), noting the remainder is zero. He concludes the block is valid. He emphasizes that the first address must be divisible by the size to ensure the host ID ranges from all 0s to all 1s.
2:00 – 3:00 02:00-03:00
The instructor proceeds to find the CIDR representation. He draws a 32-bit IP structure divided into Network ID and Host ID. Since the block size is 64, he determines that 6 bits are required for the host portion because 2^6 = 64. He subtracts these 6 host bits from the total 32 bits to find the network prefix length: 32 - 6 = 26. He writes the final CIDR notation as 150.10.20.64/26. He briefly sketches the binary values for the last octet to illustrate the range from 01000000 to 01111111. He explains that the network ID remains constant while the host ID varies across the block.
The lesson demonstrates a step-by-step algorithm for CIDR validation. First, calculate the total count of addresses. Second, verify the count is a power of 2. Third, ensure the starting address is a multiple of that count. Once validated, the host bits are derived from the log base 2 of the block size, and the prefix length is the remainder of 32 minus the host bits. This process ensures the IP block is aligned correctly within the address space.