# Tutorial 1 (Week 6) Introduction

Save this PDF as:

Size: px
Start display at page:

## Transcription

1 COMP 333/933 Computer Networks and Applications Tutorial (Week 6) Introduction Problem Set, Question 7 Suppose two hosts, A and B are separated by, kms and are connected by a direct link of R = Mbps. Suppose the propagation speed over the link is 2.5 x 8 m/s. (a) Calculate the bandwidth-delay product, R.t prop Answer: The propagation delay, tprop =, x 3 /2.5 x 8 = 4 msec. Hence, the bandwidth delay product = 4 msec x Mbps = 4, bits. (b) Consider sending a file of 4, bits from A to B. Suppose the file is sent continuously as one big message. What is the maximum number of bits that will be in the link at any given time? Answer: This is same as (a), i.e., 4, bits. (c) How long does it take to send the above file if it is sent continuously? Answer: t trans + t prop = 4 msec + 4 msec = 44 msec (d) Suppose now that the file is broken up into packets with each packet containing 4, bits. Suppose that each packet is acknowledged by the receiver and the transmission time of an acknowledgement packet is negligible. Finally, assume that the sender cannot send a packet until the preceding packet is acknowledged. How long does it take to send the file? Answer: The delay to send each packet will be t trans + t prop. However there is an additional t prop delay for the acknowledgement packet to arrive at the sender, prior to which the next packet can be transmitted. Hence the total delay to transmit packet is = * (t trans + 2 t prop ) = *(4 msec + 8 msec) =.2 sec Application Layer Problem Set 2, Question 2 Consider the figure below, for which there is an institutional network connected to the Internet. Suppose that the average object size is 9, bits and that that the average request rate from the institution s browsers to the origin server is.5 requests per second. Also suppose that the amount of time it takes from when the router on the Internet side of the access link forwards a HTTP request until it receives the response in two seconds on average. Model the total average response time as the sum of the average access delay and the average Internet delay. For the average access delay, use A/(-AB) where A is the average time required to send an object over the access link and B is the arrival rate of objects to the access link. You can assume that the HTTP request messages are negligibly small and thus create no traffic on the network or the access link.

2 COMP 333/933 Computer Networks and Applications origin servers Public Internet institutional network.5 Mbps access link Figure : Figure for web cache problem institutional cache (a) Find the total average response time. Answer: The time to transmit an object of size L over a link of rate R is L/R. The average time is the average size of the object divided by the transmission rate of the link, R: X = (9, bits)/(,5, bits/sec) =.6 sec The traffic intensity on the link is = AB= (.5 requests/sec)(.6 msec/request) =.9. Thus, the average access delay is (.6 sec)/( -.9) = 6 seconds. The total average response time is therefore 6 sec + 2 sec = 8 sec. (b) Now suppose a cache is installed in the institutional LAN. Suppose the hit rate is.4. Find the total response time. Answer: The traffic intensity on the access link is reduced by 4% since the 4% of the requests are satisfied within the institutional network. Thus, the arrival rate of the objects to the link also changes since only 6% of the objects need to be fetched from the origin servers (the rest are obtained from the cache). As a result, B=.5 x.6 =.9 requests/sec. Thus the average access delay is (.6 sec)/[ (.6)(.9)] =.2 seconds. The response time is approximately zero if the request is satisfied by the cache (which happens with probability.4); the average response time is.2 sec + 2 sec = 3.2 sec for cache misses (which happens 6% of the time). So the average response time is (.4)( sec) + (.6)(3.2 sec) =.92 seconds. Thus the average response time is reduced from 8 sec to.92 sec. 2

3 COMP 333/933 Computer Networks and Applications Question: Consider an HTTP client that wants to retrieve a web document at a given URL. The IP address of the HTTP server is initially unknown. The web document at the URL has one embedded GIF image that resides at the same server as the original document. What transport and application layer protocols besides HTTP are needed in this scenario? Answer: Before the HTTP GET request can be sent for the web document, the HTTP client needs to obtain the IP address of the HTTP server hosting the document. So a DNS request is sent out to obtain the hostname to IP address mapping. Recall that DNS runs over UDP. Once the mapping is obtained, the HTTP client first establishes a TCP connection with the server (Recall that HTTP runs over TCP). Following the TCP connection establishment a GET request for the web document is sent over this connection. In summary, the following are the protocols that are used: Application layer protocols: DNS and HTTP Transport layer protocols: UDP for DNS; TCP for HTTP Transport Layer Problem Set 3, Question 3: Solution is in the file Transport_Q3_Answer.pdf 3

4 COMP 333/933 Computer Networks and Applications Problem Set 3, Question 6 Consider the GBN and SR protocols. Suppose the sequence number space of size k. What is the largest allowable sender size window that will avoid the occurrence of the problems such as that in Figure 3.27 (of the textbook or as discussed towards the end of Week 4 lecture slides). Answer: In order to avoid the scenario of Figure 3.27, we want to avoid having the leading edge of the receiver's window (i.e., the one with the highest sequence number) wrap around in the sequence number space and overlap with the trailing edge (the one with the "lowest" sequence number in the sender's window). That is, the sequence number space must be large enough to fit the entire receiver window and the entire sender window without this overlap condition. So we need to determine how large a range of sequence numbers can be covered at any given time by the receiver and sender windows. Suppose that the lowest-sequence number that the receiver is waiting for is packet m. In this case, its window is [m, m+w-] and it has received (and ACKed) packet m- and the w- packets before that, where w is the size of the window. If the sender has yet received none of those w ACKs, then ACK messages with values of [m-w, m-] may still be propagating back. If the sender has received no ACKs with these ACK numbers, then the sender's window would be [m-w, m-]. Thus, the lower edge of the sender's window is m-w, and the leading edge of the receiver s window is m+w-. In order for the leading edge of the receiver's window to not overlap with the trailing edge of the sender's window, the sequence number space must thus be big enough to accommodate 2w sequence numbers. That is, the sequence number space must be at least twice as large as the window size, k 2w. 4

5 COMP 333/933 Computer Networks and Applications Question: Look at the graph in Figure 3 showing how the congestion window is changed over time in a TCP Reno connection. Certain parts of the graph that are of extra interest have been marked with numbers. Looking at the graph, answer the following questions. Figure 3: Congestion Window for a TCP Reno Connection (a) What is the difference of the loss events happening at and 2 in the figure? Explain why the effect on the size of the congestion window is different in the two cases. Answer: At a loss was detected through triple duplicate ACKs, while at 2 it was detected through a timeout. Since a timeout is considered worse than triple duplicate ACKs, the congestion window is decreased more drastically in that case. (b) Look at the circled segment marked as 3. What phase do you think that TCP is in? Answer: Slow Start. (c) Look at the circled segment marked as 4. What phase do you think that TCP is in? Answer: Congestion Avoidance. (d) Why is the congestion window increased more rapidly in 3 than at 4? Answer: To rapidly increase the transmission rate so that it can approach the capacity of the network briskly. This prevents the wastage of resources that would result with additive increase. Question: UDP and TCP use s complement for their checksms. Suppose you have the following three 8-bit bytes:,,. What is the s complement of the sum of these 8-bit bytes? (Note although TCP and UDP use 6-bit words in computing the checksum, for this problem we will only consider 8-bit summands). Show 5

6 COMP 333/933 Computer Networks and Applications all work. Why is that UDP takes s complement of the sum, that is, why not just use the sum? With the s complement scheme, how does the receiver detect errors? Is it possible that a -bit error will go undetected? How about a two-bit error? Answer: + + One's complement =. To detect errors, the receiver adds the four words (the three original words and the checksum). If the sum contains a zero, the receiver knows there has been an error. All one-bit errors will be detected, but two-bit errors can be undetected (e.g., if the last digit of the first word is converted to a and the last digit of the second word is converted to a ). Question: Consider a situation where you want to transfer a very large file of L bytes from Host A to Host B. Assume an MSS of,46 bytes. (7 marks) (a) What is the maximum value of L such that TCP sequence numbers are not exhausted? Recall that the TCP sequence number field has 4 bytes. Answer: There are 2 32 = 4,294,967, 296 possible sequence numbers. The sequence number does not increment by one with each segment. Rather, it increments by the number of bytes of data sent. So the size of the MSS is irrelevant -- the maximum size file that can be sent from A to B is simply the number of bytes representable by Gbytes. (b) For the value of L computed in part (a), find how long it takes to transmit the file. Assume that a total of 66 bytes of transport, network and data-link header are added to each segment before the resulting packet is sent out over a Mbps link. Ignore flow control and congestion control so that A can pump the segments back to back continuously Answer: The number of segments is = 2,94, bytes of header get added to each segment giving a total of 94,56,28 bytes of header. The total 6

7 COMP 333/933 Computer Networks and Applications 32 7 number of bytes transmitted is ,56,28 = 3,59 bits. Thus it would take 3,59 seconds = 59 minutes to transmit the file over a ~Mbps link. Question: Consider a channel that can lose packets but has a maximum RTT that is known. Modify protocol rdt2. to include sender timeout and retransmit. Informally argue why your protocol can communicate correctly over this channel. Answer: Here, we add a timer, whose value is greater than the known round-trip propagation delay. We add a timeout event to the Wait for ACK or NAK and Wait for ACK or NAK states. If the timeout event occurs, the most recently transmitted packet is retransmitted. Let us see why this protocol will still work with the rdt2. receiver. Suppose the timeout is caused by a lost data packet, i.e., a packet on the senderto-receiver channel. In this case, the receiver never received the previous transmission and, from the receiver's viewpoint, if the timeout retransmission is received, it look exactly the same as if the original transmission is being received. Suppose now that an ACK is lost. The receiver will eventually retransmit the packet on a timeout. But a retransmission is exactly the same action that is take if an ACK is garbled. Thus the sender's reaction is the same with a loss, as with a garbled ACK. The rdt 2. receiver can already handle the case of a garbled ACK 7

### Midterm Exam CMPSCI 453: Computer Networks Fall 2011 Prof. Jim Kurose

Midterm Exam CMPSCI 453: Computer Networks Fall 2011 Prof. Jim Kurose Instructions: There are 4 questions on this exam. Please use two exam blue books answer questions 1, 2 in one book, and the remaining

### CS 421: Computer Networks FALL MIDTERM I November 22, minutes

CS 421: Computer Networks FALL 2004 MIDTERM I November 22, 2004 120 minutes Name: Student No: Show all your work very clearly. Partial credits will only be given if you carefully state your answer with

### Review for Chapter 3

Review for Chapter 3 R3.Describle why an application developer might choose to run an application over UDP rather than TCP. Answer: An application developer may not want its application to use TCP s congestion

### First Midterm for ECE374 03/24/11 Solution!!

1 First Midterm for ECE374 03/24/11 Solution!! Note: In all written assignments, please show as much of your work as you can. Even if you get a wrong answer, you can get partial credit if you show your

### Final for ECE374 05/06/13 Solution!!

1 Final for ECE374 05/06/13 Solution!! Instructions: Put your name and student number on each sheet of paper! The exam is closed book. You have 90 minutes to complete the exam. Be a smart exam taker -

### First Midterm for ECE374 03/09/12 Solution!!

1 First Midterm for ECE374 03/09/12 Solution!! Instructions: Put your name and student number on each sheet of paper! The exam is closed book. You have 90 minutes to complete the exam. Be a smart exam

### Problem 1 Suppose that the client A initiates a TCP connection to a Web server whose name is S. More or less simultaneously,

Note: Here you have the original answer proposed by working groups. Spelling mistakes from original answers have not been corrected. Sometimes teacher note is included in red. Problem 1 Suppose that the

### Homework 2 assignment for ECE374 Posted: 02/21/14 Due: 02/28/14

1 Homework 2 assignment for ECE374 Posted: 02/21/14 Due: 02/28/14 Note: In all written assignments, please show as much of your work as you can. Even if you get a wrong answer, you can get partial credit

### Transport Layer Protocols

Transport Layer Protocols Version. Transport layer performs two main tasks for the application layer by using the network layer. It provides end to end communication between two applications, and implements

### Computer Networks - CS132/EECS148 - Spring 2013 ------------------------------------------------------------------------------

Computer Networks - CS132/EECS148 - Spring 2013 Instructor: Karim El Defrawy Assignment 3 - Solutions Deadline : May 9 th 9:30pm (hard and soft copies required) ------------------------------------------------------------------------------

### COMP 3331/9331: Computer Networks and Applications. Lab Exercise 3: TCP and UDP (Solutions)

COMP 3331/9331: Computer Networks and Applications Lab Exercise 3: TCP and UDP (Solutions) AIM To investigate the behaviour of TCP and UDP in greater detail. EXPERIMENT 1: Understanding TCP Basics Tools

### Study Guide for Midterm 1 CSC/ECE , Fall, 2012

Study Guide for Midterm 1 CSC/ECE 573-001, Fall, 2012 The focus of this midterm will be on the IP and transport layer protocols. Together with IP, the functions which are required for lower layer interfacing,

### COMP 361 Computer Communications Networks. Fall Semester 2003. Midterm Examination

COMP 361 Computer Communications Networks Fall Semester 2003 Midterm Examination Date: October 23, 2003, Time 18:30pm --19:50pm Name: Student ID: Email: Instructions: 1. This is a closed book exam 2. This

### TCP - Introduction. Features of TCP

TCP - Introduction The Internet Protocol (IP) provides unreliable datagram service between hosts The Transmission Control Protocol (TCP) provides reliable data delivery It uses IP for datagram delivery

### Computer Networks - CS132/EECS148 - Spring 2013 ------------------------------------------------------------------------------

Computer Networks - CS132/EECS148 - Spring 2013 Instructor: Karim El Defrawy Assignment 2 Deadline : April 25 th 9:30pm (hard and soft copies required) ------------------------------------------------------------------------------

### Solutions to the Sample Questions on Application Layer

Solutions to the Sample Questions on Application Layer 1) Why is SMTP not used for transferring e-mail messages from the recipient s mail server to the recipient s personal computer? Answer: Whereas SMTP

### First Midterm for ECE374 02/25/15 Solution!!

1 First Midterm for ECE374 02/25/15 Solution!! Instructions: Put your name and student number on each sheet of paper! The exam is closed book. You have 90 minutes to complete the exam. Be a smart exam

### EKSAMEN / EXAM TTM

1.1 1.1.1...... 1.1.6...... 1.1.2...... 1.1.3..... 1.1.4...... 1.1.5..... 1.1.7...... 1.1.8..... 1.1.9...... 1.1.10... 1.2 1.2.1...... 1.2.2...... 1.2.3..... 1.2.4...... 1.2.5..... 1.2.6...... 1.2.7......

### Lecture 6: Congestion Control

Lecture 6: Congestion Control Overview Internet is a network of networks Narrow waist of IP: unreliable, best-effort datagram delivery Packet forwarding: input port to output port Routing protocols: computing

### Chapter 3 Transport Layer

Chapter 3 Transport Layer All material copyright 1996-2009 J.F Kurose and K.W. Ross, All Rights Reserved Computer Networking: A Top Down Approach 5 th edition. Jim Kurose, Keith Ross Addison-Wesley, April

### TCP. Raj Jain. Professor of CIS The Ohio State University Columbus, OH 43210 Raj Jain 20-1

TCP Professor of CIS Columbus, OH 43210 Jain@ACM.Org http://www.cis.ohio-state.edu/~jain/ 20-1 Overview Key features, Header format Mechanisms, Implementation choices Slow start congestion avoidance, Fast

### TCP: Reliable, In-Order Delivery

TCP: Reliable, In-Order Delivery EE 122: Intro to Communication Networks Fall 2006 (MW 4-5:30 in Donner 155) Vern Paxson TAs: Dilip Antony Joseph and Sukun Kim http://inst.eecs.berkeley.edu/~ee122/ Materials

### Chapter 15. Transmission Control Protocol (TCP) TCP/IP Protocol Suite 1

Chapter 15 Transmission Control Protocol (TCP) TCP/IP Protocol Suite 1 Copyright The McGraw-Hill Companies, Inc. Permission required for reproduction or display. OBJECTIVES: To introduce TCP as a protocol

### Computer Networks UDP and TCP

Computer Networks UDP and TCP Saad Mneimneh Computer Science Hunter College of CUNY New York I m a system programmer specializing in TCP/IP communication protocol on UNIX systems. How can I explain a thing

### CS640: Introduction to Computer Networks. Transport Protocols. Functionality Split

CS640: Introduction to Computer Networks Aditya Akella Lecture 14 TCP I - Transport Protocols: TCP Segments, Flow control and Connection Setup Transport Protocols Lowest level endto-end protocol. Header

### Computer Networks Homework 1

Computer Networks Homework 1 Reference Solution 1. (15%) Suppose users share a 1 Mbps link. Also suppose each user requires 100 kbps when transmitting, but each user transmits only 10 percent of the time.

### Topics. Computer Networks. Introduction. Transport Entity. Quality of Service. Transport Protocol

Topics Introduction (6.1) Connection Issues (6. - 6..3) TCP (6.4) Computer Networks Transport Layer Introduction Efficient, reliable and cost-effective service to users (application layer) despite limitations

### Improving the Performance of TCP Using Window Adjustment Procedure and Bandwidth Estimation

Improving the Performance of TCP Using Window Adjustment Procedure and Bandwidth Estimation R.Navaneethakrishnan Assistant Professor (SG) Bharathiyar College of Engineering and Technology, Karaikal, India.

### 10/27/2014. Transport Service. The Transport Layer. Services Provided to the Upper Layers. Transport Service Primitives (1) Berkeley Sockets (1)

Transport Service The Transport Layer Chapter 6 Upper Layer Services Transport Service Primitives Berkeley Sockets Example of Socket Programming: Internet File Server Services Provided to the Upper Layers

### Prefix AggregaNon. Company X and Company Y connect to the same ISP, and they are assigned the prefixes:

Data Transfer Consider transferring an enormous file of L bytes from Host A to B using a MSS of 1460 bytes and a 66 byte header. What is the maximum value of L such that TCP sequence numbers are not exhausted?

### Programming Assignment 2 Implementing a Reliable Data Transport Protocol

Programming Assignment 2 Implementing a Reliable Data Transport Protocol 1 Objectives Since you ve learned about the socket interface and how it is used by an application; by now, you re pretty much an

### EINDHOVEN UNIVERSITY OF TECHNOLOGY Department of Mathematics and Computer Science

EINDHOVEN UNIVERSITY OF TECHNOLOGY Department of Mathematics and Computer Science Examination Computer Networks (2IC15) on Monday, June 22 nd 2009, 9.00h-12.00h. First read the entire examination. There

### Outline. Lecture 4: TCP TCP TCP. TCP Segment. How TCP Provides Reliability. Internetworking. TCP Transmission Control Protocol.

Internetworking Outline TCP Transmission Control Protocol RFC 793 (and several follow-ups) Literature: Lecture 4: TCP Forouzan, TCP/IP Protocol Suite: Ch 12 Connection Management Reliability Flow control

### Overview. Lecture 4: Congestion Control TCP. Transport. A Bit of History TCP. Internet is a network of networks

Overview Internet is a network of networks Lecture 4: Congestion Control Narrow waist of IP: unreliable, best-effort datagram delivery Packet forwarding: input port to output port Routing protocols: computing

### CSE 473 Introduction to Computer Networks. Exam 2 Solutions. Your name: 10/31/2013

CSE 473 Introduction to Computer Networks Jon Turner Exam Solutions Your name: 0/3/03. (0 points). Consider a circular DHT with 7 nodes numbered 0,,...,6, where the nodes cache key-values pairs for 60

### TCP Service Model. Announcements. TCP: Reliable, In-Order Delivery. Today s Lecture. TCP Header. TCP Support for Reliable Delivery

Announcements Sukun is away this week. Dilip will cover his section and office hours. TCP: Reliable, In-Order Delivery EE 122: Intro to Communication Networks Fall 2006 (MW 4-5:30 in Donner 155) Vern Paxson

Homework 3 1 DNS Suppose you have a Host C, a local name server L, and authoritative name servers A root, A com, and A google.com, where the naming convention A x means that the name server knows about

### TCP III - Error Control

TCP III - Error Control TCP Error Control 1 ARQ Error Control Two types of errors: Lost packets Damaged packets Most Error Control techniques are based on: 1. Error Detection Scheme (Parity checks, CRC).

### Data Networks Summer 2007 Homework #3

Data Networks Summer Homework # Assigned June 8, Due June in class Name: Email: Student ID: Problem Total Points Problem ( points) Host A is transferring a file of size L to host B using a TCP connection.

### Transmission Control Protocol (TCP) A brief summary

Transmission Control Protocol (TCP) A brief summary TCP Basics TCP (RFC 793) is a connection-oriented transport protocol TCP entities only present at hosts (end-end) retain state of each open connection

### INTERNET ENABLED SYSTEMS NETWORK PROTOCOLS

DEVICES AND COMMUNICATION BUSES FOR DEVICES NETWORK Lesson-24: INTERNET ENABLED SYSTEMS NETWORK PROTOCOLS 1 Internet enabled embedded system Communication to other on the Internet. Use html (hyper text

### Data Communication & Networks G22.2262-001. Session 9 - Main Theme The Internet Transport Protocols: TCP, UDP. Dr. Jean-Claude Franchitti

Data Communication & Networks G22.2262-001 Session 9 - Main Theme The Internet Transport Protocols: TCP, UDP Dr. Jean-Claude Franchitti New York University Computer Science Department Courant Institute

### Indian Institute of Technology Kharagpur. TCP/IP Part I. Prof Indranil Sengupta Computer Science and Engineering Indian Institute of Technology

Indian Institute of Technology Kharagpur TCP/IP Part I Prof Indranil Sengupta Computer Science and Engineering Indian Institute of Technology Kharagpur Lecture 3: TCP/IP Part I On completion, the student

### First Semester Examinations 2011/12 INTERNET PRINCIPLES

PAPER CODE NO. EXAMINER : Martin Gairing COMP211 DEPARTMENT : Computer Science Tel. No. 0151 795 4264 First Semester Examinations 2011/12 INTERNET PRINCIPLES TIME ALLOWED : Two Hours INSTRUCTIONS TO CANDIDATES

### CHAPTER 24. Questions PRACTICE SET

CHAPTER 24 PRACTICE SET Questions Q24-1. The protocol field of the datagram defines the transport-layer protocol that should receive the transport-layer packet. If the value is 06, the protocol is TCP;

### CS413: Computer Networks

CS413: Computer Networks 2005 Fall Term Midterm Exam Solution Student ID: Name: Problem No. Marks Your Marks 1 16 2 5 3 5 4 7 5 4 6 7 7 3 8 3 Total 50 1 [Marking schemes are given in blue color and the

### Sample Network Analysis Report

Sample Network Analysis Report Report Information Report created on 1/9/2014 9:35:19 PM. Analyst Information Name Sample Analysis Report E-mail Address info@chappellu.com Phone Number 408-378-7841 Client

### Answer: that dprop equals dtrans. seconds. a) d prop. b) d trans

Chapter 1 1) p. 98: P-6 This elementary problem begins to explore propagation delay and transmission delay, two central concepts in data networking. Consider two hosts, A and B, connected by single link

### Chapter 15. Transmission Control Protocol (TCP) TCP/IP Protocol Suite 1

Chapter 15 Transmission Control Protocol (TCP) TCP/IP Protocol Suite 1 Copyright The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Chapter Outline TCP/IP Protocol Suite 2

### 15-441: Computer Networks Homework 2 Solution

5-44: omputer Networks Homework 2 Solution Assigned: September 25, 2002. Due: October 7, 2002 in class. In this homework you will test your understanding of the TP concepts taught in class including flow

### TCP Header - Sequence Number

Introduction to TCP RFC 793 (+ RFC1122) (+ others) Transmission Control Protocol The Transmission Control Protocol (TCP) is intended for use as a highly reliable host-to-host protocol between hosts in

### TCP over Multi-hop Wireless Networks * Overview of Transmission Control Protocol / Internet Protocol (TCP/IP) Internet Protocol (IP)

TCP over Multi-hop Wireless Networks * Overview of Transmission Control Protocol / Internet Protocol (TCP/IP) *Slides adapted from a talk given by Nitin Vaidya. Wireless Computing and Network Systems Page

### TCP: Overview RFCs: 793, 1122, 1323, 2018, 2581

TCP: Overview RFCs: 793, 1122, 1323, 2018, 2581 socket door point-to-point: one sender, one receiver reliable, in-order byte steam: no message boundaries pipelined: TCP congestion and flow control set

### TCP in Wireless Mobile Networks

TCP in Wireless Mobile Networks 1 Outline Introduction to transport layer Introduction to TCP (Internet) congestion control Congestion control in wireless networks 2 Transport Layer v.s. Network Layer

### Note! The problem set consists of two parts: Part I: The problem specifications pages Part II: The answer pages

Part I: The problem specifications NTNU The Norwegian University of Science and Technology Department of Telematics Note! The problem set consists of two parts: Part I: The problem specifications pages

### Transport Layer Outline

Transport Layer Outline 3.1 Transport-layer services 3.2 Multiplexing and demultiplexing 3.3 Connectionless transport: UDP 3.4 Principles of reliable data transfer 3.5 Connection-oriented transport: TCP

### CS/ECE 438: Communication Networks for Computers Spring 2014 Midterm Study Guide

CS/ECE 438: Communication Networks for Computers Spring 2014 Midterm Study Guide 1. Channel Rates and Shared Media You are entrusted with the design of a network to interconnect a set of geographically

### TCP (Transmission Control Protocol)

TCP (Transmission Control Protocol) Originally defined in RFC 793 (September 1981) UDP features: multiplexing + protection against bit errors Ports, checksum Connection-oriented Establishment and teardown

### Transportation Protocols: UDP, TCP & RTP

Transportation Protocols: UDP, TCP & RTP Transportation Functions UDP (User Datagram Protocol) Port Number to Identify Different Applications Server and Client as well as Port TCP (Transmission Control

### CMPE 150 Winter 2009

CMPE 150 Winter 2009 Lecture 6 January 22, 2009 P.E. Mantey CMPE 150 -- Introduction to Computer Networks Instructor: Patrick Mantey mantey@soe.ucsc.edu http://www.soe.ucsc.edu/~mantey/ / t / Office: Engr.

### Guide to TCP/IP, Third Edition. Chapter 5: Transport Layer TCP/IP Protocols

Guide to TCP/IP, Third Edition Chapter 5: Transport Layer TCP/IP Protocols Objectives Understand the key features and functions of the User Datagram Protocol Explain the mechanisms that drive segmentation,

### La couche transport dans l'internet (la suite TCP/IP)

La couche transport dans l'internet (la suite TCP/IP) C. Pham Université de Pau et des Pays de l Adour Département Informatique http://www.univ-pau.fr/~cpham Congduc.Pham@univ-pau.fr Cours de C. Pham,

### Transports and TCP. Adolfo Rodriguez CPS 214

Transports and TCP Adolfo Rodriguez CPS 214 Host-to to-host vs. Process-to to-process Communication Until now, we have focused on delivering packets between arbitrary hosts connected to Internet Routing

### TCP PERFORMANCE IN MOBILE-IP

TCP PERFORMANCE IN MOBILE-IP Foo Chun Choong Department of Electrical Engineering, National University of Singapore ABSTRACT The throughput performance of TCP in Mobile-IP [1] was investigated. Compared

### CSE331: Introduction to Networks and Security. Lecture 9 Fall 2006

CSE33: Introduction to Networks and Security Lecture 9 Fall 2006 Announcements Project Due TODAY HW Due on Friday Midterm I will be held next Friday, Oct. 6th. Will cover all course material up to next

### - TCP and UDP - Transport Layer Protocols

1 Transport Layer Protocols - TCP and UDP - The Transport layer (OSI Layer-4) does not actually transport data, despite its name. Instead, this layer is responsible for the reliable transfer of data, by

### Good Ideas So Far Computer Networking. Outline. Sequence Number Space. Lecture 18 More TCP & Congestion Control. The devilish details of TCP

Good Ideas So Far 15-441 Computer Networking Lecture 18 More TCP & Congestion Control Flow control Stop & wait Parallel stop & wait Sliding window (e.g., advertised windows) Loss recovery outs Acknowledgement-driven

### By: Chunyan Fu, PhD, Ericsson Canada

TCP/UDP Basics By: Chunyan Fu, PhD, Ericsson Canada Internet Model Application TCP/UDP IP Link layer Physical layer Transport Service Overview Provide service to application layer by using the service

### Computer Networks. Data Link Layer

Computer Networks The Data Link Layer 1 Data Link Layer Application Transport Network DLL PHY 2 What does it do? What functions it performs? Typically: Handling transmission errors, a.k.a., error control.

### Stop And Wait. ACK received; transmit frame 2 CS 455 3

Data Link Layer, Part 5 Sliding Window Protocols These slides are created by Dr. Yih Huang of George Mason University. Students registered in Dr. Huang's courses at GMU can make a single machine-readable

### Names & Addresses. Names & Addresses. Hop-by-Hop Packet Forwarding. Longest-Prefix-Match Forwarding. Longest-Prefix-Match Forwarding

Names & Addresses EE 122: IP Forwarding and Transport Protocols Scott Shenker http://inst.eecs.berkeley.edu/~ee122/ (Materials with thanks to Vern Paxson, Jennifer Rexford, and colleagues at UC Berkeley)

### CSCE 463/612 Networks and Distributed Processing Spring 2016

CSCE 463/612 Networks and Distributed Processing Spring 2016 Transport Layer IV Dmitri Loguinov Texas A&M University March 10, 2016 Original slides copyright 1996-2004 J.F Kurose and K.W. Ross 1 Chapter

### Module 11: TCP/IP Transport and Application Layers

Module 11: TCP/IP Transport and Application Layers 11.1 TCP/IP Transport Layer 11.1.1 Introduction to the TCP/IP transport layer The primary duties of the transport layer are to transport and regulate

### Due for Week Group of 3 (max) Percentage awarded for comments, coding practice, layout style, naming convention, completed task.

EE4607 Project Goals Details Due for Week 11-12. Group of 3 (max) Percentage awarded for comments, coding practice, layout style, naming convention, completed task. Task Create a SDL implementation of

### Advanced Computer Networks Project 2: File Transfer Application

1 Overview Advanced Computer Networks Project 2: File Transfer Application Assigned: April 25, 2014 Due: May 30, 2014 In this assignment, you will implement a file transfer application. The application

### Solutions to the Sample Questions on Introduction

Solutions to the Sample Questions on Introduction NOTE: Pay close attention to units. A byte of storage is 8-bits, and 1 kilobits of storage is1024 bits. By convention, the rules are different between

### 6.1. Why do LANs tend to use broadcast networks? Why not use networks consisting of multiplexers and switches?

TUTORIAL 2 (EKT 332) 6.1. Why do LANs tend to use broadcast networks? Why not use networks consisting of multiplexers and switches? Why broadcast network? -The computers in a LAN are separated by a short

### Computer Systems: TCP - Adaptive Distributed Reliable Transport Protocol

Computer Systems: TCP - Adaptive Distributed Reliable Transport Protocol Presenter: Sandeep K. S. Gupta Reference: -- Chapter 3, 5 Computer Networking, Kurose and Ross, Addison Wesley - Chapter 7, An Engineering

### To see the details of TCP (Transmission Control Protocol). TCP is the main transport layer protocol used in the Internet.

Lab Exercise TCP Objective To see the details of TCP (Transmission Control Protocol). TCP is the main transport layer protocol used in the Internet. The trace file is here: http://scisweb.ulster.ac.uk/~kevin/com320/labs/wireshark/trace-tcp.pcap

### Internet Protocol Stack. TCP: Transmission Control Protocol

Internet Protocol tack application: supporting network applications HTTP, MTP, FTP, etc transport: endhost-endhost data transfer TCP, UP network: routing of datagrams from source to destination IP, routing

### Process-to. to-process Communication. Transports and TCP. A Brief Internet History UDP. TCP Timeline. TCP: After 1990

Transports and TCP Adolfo Rodriguez CPS 214 Host-to to-host vs. Process-to to-process Communication Until now, we have focused on delivering packets between arbitrary hosts connected to Internet Routing

### RSC Part III: Transport Layer 3. TCP

RSC Part III: Transport Layer 3. TCP Redes y Servicios de Comunicaciones Universidad Carlos III de Madrid These slides are, mainly, part of the companion slides to the book Computer Networking: A Top Down

### CS268 Exam Solutions. 1) End-to-End (20 pts)

CS268 Exam Solutions General comments: ) If you would like a re-grade, submit in email a complete explanation of why your solution should be re-graded. Quote parts of your solution if necessary. In person

### CSE331: Introduction to Networks and Security Homework 1 Fall 2006 Due: 29 Sept. 2006

CSE331: Introduction to Networks and Security Homework 1 Fall 006 Due: 9 Sept. 006 What to turn in: Submit hardcopy answers to the questions below. Please include your name, e-mail address, and the number

### La couche transport dans l'internet (la suite TCP/IP)

La couche transport dans l'internet (la suite TCP/IP) C. Pham RESO-LIP/INRIA Université Lyon 1 http://www.ens-lyon.fr/~cpham Basé sur les transparent de Shivkumar Kalyanaraman La couche transport dans

### Transport Control Protocol (TCP)

Transport Control Protocol (TCP) Richard T. B. Ma School of Computing National University of Singapore CS 3103: Compute Networks and Protocols Transport services and protocols provide logical communication

### Tutorial for Chapter 1

Tutorial for Chapter 1 CEN 444 Computer Networks Dr. Mostafa Dahshan Department of Computer Engineering College of Computer and Information Sciences King Saud University mdahshan@ksu.edu.sa Tutorial for

### Introduction. Abusayeed Saifullah. CS 5600 Computer Networks. These slides are adapted from Kurose and Ross

Introduction Abusayeed Saifullah CS 5600 Computer Networks These slides are adapted from Kurose and Ross Roadmap 1.1 what is the Inter? 1.2 work edge end systems, works, links 1.3 work core packet switching,

### Professor: Ian Foster TAs: Xuehai Zhang, Yong Zhao. Winter Quarter. www.classes.cs.uchicago.edu/classes/archive/2003/winter/54001-1

Professor: Ian oster Ts: Xuehai Zhang, Yong Zhao Winter Quarter www.classes.cs.uchicago.edu/classes/archive//winter/541-1 alculate the total time required to transfer a 1 KB file (RTT=1 ms, packet size

### Key Components of WAN Optimization Controller Functionality

Key Components of WAN Optimization Controller Functionality Introduction and Goals One of the key challenges facing IT organizations relative to application and service delivery is ensuring that the applications

### Transport Layer: UDP vs. TCP

EEC 189Q: Computer Networks Transport Layer: UDP vs. TCP Reading: 8.4 & 8.5 Review: Internet Protocol Stack Application Telnet FTP HTTP Transport Network Link Physical bits on wire TCP LAN IP UDP Packet

### Guide to TCP/IP Fourth Edition. Chapter 9: TCP/IP Transport Layer Protocols

Guide to TCP/IP Fourth Edition Chapter 9: TCP/IP Transport Layer Protocols Objectives Explain the key features and functions of the User Datagram Protocol and the Transmission Control Protocol Explain,

### The following reference answers are based on the trace files provided with the text book, which can be downloaded from the textbook website.

Wireshark Lab 3 TCP The following reference answers are based on the trace files provided with the text book, which can be downloaded from the textbook website. TCP Basics Answer the following questions

### Computer Networks. Chapter 5 Transport Protocols

Computer Networks Chapter 5 Transport Protocols Transport Protocol Provides end-to-end transport Hides the network details Transport protocol or service (TS) offers: Different types of services QoS Data

### Data Communications & Networks. Session 6 Main Theme Reliable Data Transfer. Dr. Jean-Claude Franchitti

Data Communications & Networks Session 6 Main Theme Reliable Data Transfer Dr. Jean-Claude Franchitti New York University Computer Science Department Courant Institute of Mathematical Sciences Adapted

### Transmission Control Protocol (TCP) Reliable Connection-oriented Point-to-point Full-duplex Streams, not messages

Transmission Control Protocol (TCP) Reliable Connection-oriented Point-to-point Full-duplex Streams, not messages Initialization: 3 Way Handshake Initiator SYN (Synchronization Sequence Number) SYN = ISN

### TCP/IP Revisited. IP s Transport Layer UDP and TCP. Computer Science 742 S2C, 2010 TCP UDP

TCP/IP, COMPSCI 742, 2010 p. 3/29 IP s Transport Layer UDP and TCP TCP/IP, COMPSCI 742, 2010 p. 4/29 TCP/IP Revisited Computer Science 742 S2C, 2010 Nevil Brownlee, with acknowledgements to Ulrich Speidel

### Homework 2 assignment for ECE374 Posted: 02/20/15 Due: 02/27/15

1 Homework 2 assignment for ECE374 Posted: 02/20/15 Due: 02/27/15 ote: In all written assignments, please show as much of your work as you can. Even if you get a wrong answer, you can get partial credit