Questions and Solutions for Chapter 2
1. Which of the following data units has an application-layer message plus the header from
a. a frame
b. a user datagram
c. a bit
The data unit should belong to layer 4. In this case, it is a user datagram.
2 out of 2 points
Which of the following cannot be the value of TTL field in a datagram?
4 out of 4 points
An IPv4 datagram has arrived with the first few hexadecimal digits a
The Internet model consists of _ layers.
The process-to-process delivery of the entire message is the responsibility of
the _ layer.
The _ l
Before data can be transmitted, they must be transformed to _.
D)low-frequency sine waves
A periodic signal completes one cycle in 0.001 s. What is the frequency?
The sharing of a medium and its link by two or more devices is called _.
Which multiplexing technique transmits analog signals?
D)(a) and (c)
Unipolar, bipolar, and polar encoding are types of _ encoding.
_ encoding has a transition at the middle of each bit.
The correct answer for each question is indicated by a
The _ is the physical path over which a message travels.
The information to be communicated in a data communications system is t
Solutions for Chapter 4
The three different techniques described in this chapter are line coding, block
coding, and scrambling.
When the voltage level in a digital signal is constant for a while, the spectrum
creates very low frequencies, called
Solutions for Questions in Chapter 1
1. What is the difference between half-duplex and full-duplex transmission modes? (Q 1-6)
In half-duplex transmission, only one entity can send at a time; in a full duplex transmission, both
entities can send at the sa
Solutions for Chapter 3
The period of a signal is the inverse of its frequency and vice versa: T = 1/f and f = 1/T.
The amplitude of a signal measures the value of the signal at any point.
The frequency of a signal measures how many times
Name: Alice Eunsong Kim
Course Information: CECS516
Lab Number: Lab 1
Title: Office Bus Network with several Scenarios
Submission Date: Feb. 9
Summary & Objective
Lab 1 was about checking network traffic, and Collision. In theoretically, if sending messag
Extra Materials for Chapter 10
In this document, we discuss three topics that were briefly mentioned in Chapter 10 of
the textbook: CRC hardware implementation, CRC polynomial representation, and
One of the
Q31-1. Only snooping is a threat to confidentiality. Masquerading and repudiation are
threats to integrity.
Q31-3. Only denial of service is a threat to availability. Repudiation and modification
are threats to integrity.
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; if the value is 17, the protocol is UDP.
Q24-3. UDP i
Q21-1. In multicasting, the sender host sends only one copy of the message, but it is
multiplied at the routers if needed; all multiplied copies have the same destination address. In multiple-unicasting, the sender host s
Q25-1. No changes are needed. The new protocol needs to use the services provided
by one of the transport-layer protocols.
Q25-3. A server should always be on because a client may need to access it at any
time. A client i
Q27-1. Fault and performance are areas of management defined by OSI; personnel is
Q27-3. This is related to hardware reconfiguration, which is part of reconfiguration,
which is in turn part of configuration managemen
Q28-1. In dictionary coding, the number of iterations in the loop is one less than the
number of characters in the message. In this case, the number of iterations is
Q28-3. In a Huffman tree, the number of leaves is t
Q32-1. IPSec needs a set of security parameters before it can be operative. In IPSec,
the establishment of the security parameters is done via a mechanism called
security association (SA).
Q32-3. The two protocols defined
Q13-1. In a full-duplex Ethernet, each station is connected to the switch and the
media is divided into two channels for sending and receiving. No two stations
compete to access the channels; each channel is dedicated.
Q30-1. We cannot define the absolute order, but in normal situation we will rank them
Q30-3. We cannot define the absolute order, but in normal situation we will rank them
Q14-1. The telephone network is made of three major components: local loops,
trunks, and switching offices.
Q14-3. Signaling System Seven (SS7) is the protocol used to provide signaling services in the telephone network.
Q26-1. Probably Alice turned off her desktop, which stopped the FTP server, when
she left the office. A server process should be running all the time, waiting for
clients to access it.
Q26-3. In an HTTP request message, a
Extra Materials for Chapter 22
In this document, we discuss four topics that were briefly mentioned in Chapter 4 of the
textbook: IPv4 options, ICMPv4 packets, IPv6 extension headers, and ICMPv6 packets. These materials may be useful for those