TCP Header-Sequence Number-Acknowledgement Number

Duration: 13 min

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Module outline

  1. General Intelligence & Reasoning: Analogy, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Blood Relations, Directions (Direction Test), Ranking, Order and Sequence, Logical Sequence Of Words, Syllogisms, Venn Diagram, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Selection Decision Table (Decision Making), Data Sufficiency, Puzzle Solving (Puzzles), Data Arrangement, Cubes & Dices, Calendar, Clock, Arithmetic, Number System, HCF LCM, Verbal Analogy (Word Based Analogy), Visual Recognition and Figure Completion, Paper Folding and Cutting, Transformation of Shapes, Clocks and Calendars, Direction Sense, Cubes and Dice, Patterns in Two-Dimensional Figures, Seating Arrangements, Analogy and Classification, Logical Deduction and Induction, Alphabet and Word Tests, Mathematical Operations, Series Completion, Simplification and Approximation, Coding and Decoding, Numerical Reasoning, Assembling and Grouping of Shapes, Three-Dimensional Patterns and Visualization, Vocabulary, Number System, Averages, Mixtures and Alligation, Simple and Compound Interest, Percentages, Algebra, Speed, Time and Distance, Seating and Arrangement Puzzles, Traverse Surveying, Order, Ranking and Sequence, Constraint Puzzles, Syllogisms and Venn Diagrams, Reading Comprehension, Critical Reasoning, Permutations and Combinations, Narrative Sequencing, Project Monitoring, Resources and Safety, Profit, Loss and Discount, Ratio and Proportion, Time and Work, Mensuration, Data Interpretation, Powers, Surds and Logarithms, Sequences and Series, Articles and Determiners, Sentence Completion, Data Sufficiency, Blood Relations, Simple Interest and Compound Interest, Mixture and Alligation, Sequence and Series (Series), Speed Time and Distance, Algebra, Profit and Loss, Powers and Exponents (Surds and Indices), Permutation and Combination
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  3. Engineering Mathematics: Set Theory, Relations, Functions, Graph Theory, Group Theory, Propositional and Predicate Logic, Linear Algebra, Calculus, Probability, Statistics, Signal Space and Optimum Detection, Probability, Statistics
  4. Digital Logic: Digital Systems & Boolean Basics, Logic Gates & Hardware, Boolean Expression, Boolean Minimization, Combinational Circuit, Sequential Circuits, Number System, Number Representation, Floating Point Rep, Number Systems and Codes, Registers and Counters, Boolean Algebra and Logic Gates, Microprocessors and Microcontrollers, Logic Families and CMOS Logic, Microprocessors, Logic Gates and Boolean Algebra, Minimization of Boolean Functions, Timing, Hazards and Testing, Logic Families, Combinational Logic Design, Arithmetic Circuits, Waveform Generators and Timer Circuits, Semiconductor Memories and Programmable Logic Devices, Combinational Logic Circuits, Latches and Flip-Flops, Finite State Machines, Sequential Circuits and State Machines, Minimization of Boolean Functions, Arithmetic Circuits, Latches and Flip-Flops, Number Systems and Codes, Registers and Counters
  5. Computer Organisation & Architecture: Basics of COA, Cache Memory Organization, Input Output Organisation, Pipelining, Instr Formats & Modes, Control Unit Design, Programming the Basic Computer, Register Transfer and Microoperations, Semiconductor Memories and Programmable Logic, Processor Organization and Instructions, Memory Hierarchy and Input/Output, Registers and Counters
  6. Programming & Data Structures: C Fundamentals, Control Flow, Functions, Arrays & Pointers, Storage Classes, Structures & Enums, DMA, Macros, Scoping & File Handling, Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing, HTML Basics, OOPS with C++, Java, Object Oriented Technology
  7. Databases: 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, Database Security & Authorization
  8. Algorithms: Algorithm Analysis, Time Complexity Analysis, Sorting Algorithms, Greedy Algorithms, Dynamic Programming, Minimum Spanning Trees, Shortest Path Algos
  9. Theory of Computation: 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
  10. Compiler Design: 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
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  12. Computer Networks: Introduction to CN, 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, Data Communication, Website, Browser & Services, Web Design & Development, Network Security, Cyber Threats and Malware Attacks, Cyber Safety and Security
  13. Full Length Mock Tests:
  14. Sectional Tests:
  15. Paper 2 - Full-length Mock Tests:
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

This lecture introduces TCP sequence numbers as a 32-bit field that assigns a number to the first byte of data in each segment, emphasizing that TCP is a stream transport protocol where every byte is numbered. The instructor explains that sequence numbers range from 0 to 2^32 - 1 and are initialized with an arbitrary Initial Sequence Number (ISN) chosen randomly to avoid duplication. A worked example demonstrates calculating sequence numbers for a 5000-byte file transferred in five 1000-byte segments, starting with byte number 10001. The solution shows segment ranges from 10,001-11,000 through 14,001-15,000, with each segment's sequence number equal to the previous segment's starting number plus the bytes carried. The lecture also notes that numbering is independent in each direction and does not necessarily start from 0, contrasting TCP's byte-level counting with IP's packet-based approach.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The lecture begins by defining the TCP sequence number as a 32-bit field that numbers every byte of data transmitted. The instructor points to the sequence number and acknowledgment number fields in a TCP header diagram, noting that numbering is independent in each direction. The slide states 'Sequence number is 32-bit field' and 'maximum number of possible sequence numbers = 2^32'. The lesson transitions to the concept of byte numbers, explaining that TCP chooses an arbitrary initial sequence number (ISN) between 0 and 2^32 - 1 to avoid duplication. The instructor then introduces a worked example: 'Suppose a TCP connection is transferring a file of 5000 bytes. The first byte is numbered 10001.'

  2. 2:00 – 5:00 02:00-05:00

    The instructor works through the TCP sequence number example on a whiteboard, writing 'S' and 'R' to denote sender and receiver. The problem asks for sequence numbers of five segments, each carrying 1000 bytes, starting with byte number 10001. The instructor progressively writes the byte ranges for each segment: '10,001 - 11,000', '11,001 - 12,000', '12,001 - 13,000', '13,001 - 14,000', and '14,001 - 15,000'. The sequence number for the first segment is written as '10,001' inside the first box. The instructor circles '10001' to emphasize it as the initial sequence number and draws arrows representing segments. The teaching cue emphasizes that the sequence number for a segment is the number of its first byte, and each subsequent segment's range starts where the previous one ended plus one.

  3. 5:00 – 10:00 05:00-10:00

    A slide titled 'Sequence number' lists bullets noting the field is 32 bits and that values lie in 'the range [0, 2^32 -1]'. The TCP segment diagram labels 'Sequence number 32 bits' and 'Acknowledgement number 32 bits', with a handwritten '32' arrowed to the sequence field. The whiteboard example states a file of 5000 bytes with first byte 'numbered 10001', and handwritten boxes show segment ranges from '10,001 - 11,000' through '14,001 - 15,000'. A 'Byte Number' slide underlines that 'Numbering is independent in each direction' and that numbering 'does not necessarily start from 0'. The instructor's hand points to the top box '10,001' while a circled '10001' and an arrow toward '5000' sit on the left side of the board. The slide also states 'Sequence number is 32-bit field defines the number assigned to the first byte of data contained in this segment'.

  4. 10:00 – 12:50 10:00-12:50

    The video concludes by solving the numerical example where sequence numbers for five 1000-byte TCP segments are calculated, starting from an initial byte number of 10001. The instructor transitions to a theoretical slide explaining the concept of sequence numbers, defining them as a 32-bit field that assigns a number to the first byte of data in each segment. The explanation highlights that sequence numbers are generated randomly during connection establishment to avoid duplication and follow a specific calculation rule based on the previous segment. The teaching cue emphasizes that TCP is a stream transport protocol where every byte is numbered, unlike IP which counts packets. The final slide shows a TCP segment header diagram with labeled fields including 'Source port address 16 bits', 'Destination port address 16 bits', 'Sequence number 32 bits', and 'Acknowledgement number 32 bits'.

The lecture systematically builds understanding of TCP sequence numbers through definition, diagram, and worked example. The central concept is that TCP uses a 32-bit sequence number field to assign a unique number to the first byte of data in each segment, with values ranging from 0 to 2^32 - 1. The Initial Sequence Number (ISN) is chosen randomly to prevent duplication, and numbering is independent in each direction of the connection. The worked example demonstrates the practical application: for a 5000-byte file with first byte numbered 10001, sent in five 1000-byte segments, the sequence numbers are 10,001; 11,001; 12,001; 13,001; and 14,001. The key rule is that each segment's sequence number equals the previous segment's starting number plus the bytes carried. This contrasts with IP, which counts packets rather than bytes, highlighting TCP's stream-oriented nature.

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