DATA LINK CONTROL (DLC)
OBJECTIVE: PROVIDE AN
ERROR FREE BIT PIPE
PACKET
Chapter 3
PACKET
DLC
Data Link Layer &
Error Control Coding
HEADER
SEQUENCE
NUMBERS
FRAME
Do Young Eun
DATA LINK CONTROL (2)
RELIABLE
BIT PIPE
DLC
ECE/CSC 570, Fall 2012
Functions of
ECE/CSC 570 - Sections 3 and 601, Computer Networks
Homework #5 (Due on Nov. 27, 2012)
Grading TA: Xin Xu
1. (10 points) In the lecture note for Quality of Service, slide # 29, Show your steps
to obtain the gure (f). In particular, explain how you can get
ECE/CSC 570 - Sections 3 and 601, Computer Networks
Fall 2012, Homework #2 Solutions
1. (10 points) In a constellation diagram, eight points lie on a circle of radius A centered
on the origin. Label these 8 points as s0 (t), S1 (t), . . . , S7 (t) (starti
Introduction: Roadmap
Chapter 1: Introduction
What is computer network / Internet ?
network structure: edge vs. core
Network core
circuit switching vs. packet switching
multiplexing, delay calculation
applications
ECE/CSC 570, Fall 2012
Protocol layers, s
ECE/CSC 570 Sections 3 and 601, Computer Networks, Fall 2012
OPNET Lab #2
Due Date: Nov. 20 (in class) for on-campus students
Nov. 21, 11:59PM for EOL students
Responsible TA: Shalini Chauhan, [email protected]
1
Objective
This Lab #2 is aimed at getting y
Why Probability ?
Area of mathematics most fundamentally related to
computer networking
ECE/CSC 570
Extensive use in modeling network traffic
Leads on to more powerful analysis tools and modeling
paradigms
Markov chains
Probability Theory Review
Queuing
ECE/CSC 570 - Sections 3 and 601, Computer Networks
Homework #2 (Due on Sept. 18, 2012)
While this HW#2 is rather long and contains more challenging problems than those in
HW#1, I suggest you try (with struggle) to solve all of these on your own, as it is
ECE/CSC 570 - Sections 3 and 601, Computer Networks
Homework #3 (Due on Sept. 27, 2012)
You are strongly recommended to read relevant sections in Chapter 3 of the main reference
(Tanenbaum).
1. (15 points) A 9-bit message with binary value 100101011 is to
ECE/CSC 570 - Sections 3 and 601, Computer Networks
Homework #5 Solution, Grading TA: Xin Xu
1. (10 points) In the lecture note for Quality of Service, slide # 29, Show your steps
to obtain the gure (f). In particular, explain how you can get the burst le
ECE/CSC 570 - Sections 3 and 601, Computer Networks
Fall 2012, Homework #1 Solutions
1. (6 points) Which of the OSI layers handle each of the following:
(a) Providing reliable, connection-oriented path between source and destination.
Solution: Transport L
ECE/CSC 570 - Sections 3 and 601, Computer Networks
Homework #4 (Due on Nov. 1, 2012)
Grading TA: Xin Xu
You are strongly recommended to read relevant sections in Chapter 4 of the main reference
(Tanenbaum).
1. (20 points) Consider a nite population slott
ECE/CSC570001,601,Fall,2010
Study Guide 2
DataLinkControlMediumAccessControl
1. (Tanenbaum, 4.3) Consider the delay of pure ALOHA versus slotted ALOHA at low
load. Which one is less? Explain your answer.
1. At low load, no collisions are likely. In slotte
ECE/CSC 570 - Sections 3 and 601, Computer Networks
Fall 2012, Homework #3 Solutions
1. (15 points) A 9-bit message with binary value 100101011 is to be encoded using an
even-parity Hamming code (as in class notes). What is the binary value after encoding
ECE/CSC 570 - Sections 3 and 601, Computer Networks
Homework #4 Solution, Grading TA: Xin Xu
1. (20 points) Consider a nite population slotted ALOHA with N users, each of which
generates a frame with probability p during each slot, independently of all ot
There was a tail in the beginning of the data due to the first 11 values. These were removed and the training data starts from value 12 till value 1500. The rest is testing data.
Task 1 is performed using excel to obtain the forecast time series. The exce
ECE/CSC 570, Computer Networks, Fall 2016
Homework #4 Solution
1. (15 points: 5 points each) A large (infinite) population of ALOHA users manages to
generate according to a Poisson process with 200 requests/sec (from all users) on average,
including both
In task 1 the value of the window size k(m in given pdf) was varied from 2-7.
The RMSE vs k graph is plotted and shows that RMSE value is minimum for k=2.
Hence k=2 is the optimum value.
In task 2 the value of a(or aplha) was varied first from 0.1 to 0.9
Transport services and protocols
Chapter 6: Transport Layer
Transport protocols run in end
systems
Reliable, in-order unicast
delivery: TCP
network
data link
physical
connection setup
network
data link
physical
Unreliable (best-effort),
unordered unicast
ECE/CS 356: Computer Network Architecture
Homework 1 Solution
Note: If you showed no work but got the answer correct, I gave half credit. If you gave the
incorrect answer and showed no work you got no credit. If you showed work but gave an
incorrect answe
Omran Alrowahi1
Fall 2015 -CSC/ECE 570 Computer
Networks - Homework #8
Question 1 (6p) Assume that the slow-start threshold ssthresh= 8 MSS is used in TCP Reno,
a time out occurs on the 6-th acknowledgment, and triple duplicate acks on the 10-th
acknowled
Omran Alrowahi 1
Fall 2015 -CSC/ECE 570 Computer
Networks - Homework #4
Question 1 (4p) Automatic Repeat ReQuest (ARQ) re-transmission is a widely used scheme
in computer networks, like in TCP. This toy example illustrates the rationale behind the basic
i
Omran Alrowahi 1
Fall 2015 -CSC/ECE 570 Computer
Networks - Homework #3
Question 1 (5p) There are 4 switches in a circuit-switching network that connects computers
A and B. Each switch has a failure probability of 0.1. Assume these switches work
independe
Omran Alrowahi 1
Fall 2015 -CSC/ECE 570 Computer
Networks - Homework #6
Question 1 (6p) In Go-Back-N protocol, assume the window size W = 4, and the sequence
number is from 0-7, that is, [0,1,2,3,4,5,6,7]. Assume that the following events happen during th
Fall 2015 -CSC/ECE 570 Computer Networks - Homework #7
Question 1 (4p) Consider a CSMA/CD local area network with transmission rate of 10 Mbps.
Assume that exponential backoff time is used for random access. Answer the following
questions:
a) After the 4t