Congestion Detection Phase Phase-1
Duration: 4 min
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Module outline
- 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
- General Awareness: Physics, Chemistry, Biology, History, Geography, Polity, Indian Economy, Environment, Static General Knowledge, GK- Current Affairs, Artificial Intelligence, MS Office Applications, Terms & Abbreviations, Keyboard Shortcuts, Evolution of Indian Banking (Banking & Financial Awareness), Emerging Tech Trends
- 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
- 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
- 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
- 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
- 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
- Algorithms: Algorithm Analysis, Time Complexity Analysis, Sorting Algorithms, Greedy Algorithms, Dynamic Programming, Minimum Spanning Trees, Shortest Path Algos
- 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
- 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
- Operating System: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Threads & Process Creation, Deadlock, Memory Management, Virtual Memory, Disc Scheduling, File Management, Security, Windows OS, Distributed Systems, Unix OS, Linux OS
- 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
- Full Length Mock Tests:
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AI summary & chapters
AI Summary
An AI-generated summary of this video lecture.
This lecture segment explains the Congestion Detection Phase in TCP, specifically how a sender reacts when loss is detected via timeout. The instructor presents a slide titled “Congestion Detection Phase” and introduces the sub-heading “Detection On Time Out,” defining it as the situation where the “Time Out Timer expires before receiving the acknowledgement for a segment.” The reaction steps are listed: setting the slow start threshold to half of the current congestion window size, decreasing the congestion window size to 1 MSS, and resuming the slow start phase. A graph of Congestion Window (cwnd) versus Round Trip Transmission (RTT) is used to illustrate the slow start and congestion avoidance phases, with annotations for “Slow start,” “Congestion Avoidance,” “Threshold (ssthresh),” and the “Congestion point of network.” The graph shows exponential growth during slow start, linear growth during congestion avoidance, and a drop in cwnd at the congestion point. The instructor points to these phases and the threshold line, emphasizing how timeout recovery resets the window and restarts slow start. The content is grounded in visible slide text and graph labels; no audio transcript is available, so explanations are inferred from on-screen cues.
Chapters
0:00 – 2:00 00:00-02:00
The video opens with the slide “Congestion Detection Phase” and introduces “Detection On Time Out,” defined by the red-underlined line: “Time Out Timer expires before receiving the acknowledgement for a segment.” The reaction steps are listed, including “Setting the slow start threshold to half of the current congestion window size,” “Decreasing the congestion window size to 1 MSS,” and “Resuming the slow start phase.” A graph of Congestion Window (cwnd) versus Round Trip Transmission (RTT) is displayed, showing the “Slow start” and “Congestion Avoidance” phases. The graph illustrates exponential growth during slow start, linear growth during congestion avoidance, and a drop in cwnd at the “Congestion point of network.” The instructor points to the “Threshold (ssthresh)” line and highlights the congestion point at the peak of the graph.
2:00 – 4:06 02:00-04:06
The lecture continues with the same “Congestion Detection Phase” slide, reinforcing that the sender reacts differently depending on how loss is detected. The “Detection On Time Out” sub-heading and its definition are revisited, with the reaction steps circled using a red hand-drawn bracket. The text slide details the specific actions taken upon detecting loss via timeout, such as resetting thresholds and window sizes. The instructor underlines key terms like “before” and “strong possibility of congestion,” emphasizing the significance of timeout as a signal for network congestion. The graph remains visible, illustrating the cwnd dynamics and the transition from slow start to congestion avoidance, with the threshold line clearly marked.
The core teaching point is that TCP congestion detection via timeout triggers a specific recovery sequence: halving the slow start threshold, resetting the congestion window to 1 MSS, and resuming slow start. This is visually reinforced by a cwnd vs RTT graph that distinguishes exponential growth (slow start) from linear growth (congestion avoidance) and shows the cwnd drop at congestion. The instructor uses annotations, underlining, and hand-drawn brackets to highlight key terms and steps, ensuring students connect the textual reaction rules with the graphical behavior. The lesson emphasizes that timeout is a strong indicator of congestion, prompting conservative window reduction to prevent further network overload.

