EBK COMPUTER NETWORKING
7th Edition
ISBN: 8220102955479
Author: Ross
Publisher: PEARSON
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Chapter 2, Problem P8P
a)
Program Plan Intro
DNS:
DNS stands for Domain Name System. It is the way that internet domain names are located and translated into internet protocol address.
TCP:
TCP stands for Transmission Control Protocol which is a standard that establishes and maintain a network conversion with the use of application programs.
Round Trip Time (RTT):
The length of time it takes for a signal to be sent along with the length of time to be acknowledged is called the round trip time.
There are “n” DNS servers in the connection.
Amount of elapsed time:
While clicking on a link to open a web page, the IP address of the associated web page is not cached in the local host and hence a DNS lookup is used to identify the local host.
As the webpage is not cached and therefore must be found before the file can be requested and then received by the contacting host.
It is given that visits to “n” DNS servers to find the site occur a round-trip time (RTT) which adds up to “RTT1, RTT2,… RTTn” ,in which the numbers of RTT represents the DNS number.
- Therefore the total time it takes for the host to obtain the IP address can be denoted as: “RTT1+RTT2+RTT3+…RTTn”.
Given Data:
The HTML file references eight very small objects on the same server.
To Find:
Non Persistent HTTP with no parallel TCP connections:
b)
Program Plan Intro
DNS:
DNS stands for Domain Name System. It is the way that internet domain names are located and translated into internet protocol address.
TCP:
TCP stands for Transmission Control Protocol which is a standard that establishes and maintain a network conversion with the use of application programs.
Round Trip Time (RTT):
The length of time it takes for a signal to be sent along with the length of time to be acknowledged is called the round trip time.
There are “n” DNS servers in the connection.
Amount of elapsed time:
While clicking on a link to open a web page, the IP address of the associated web page is not cached in the local host and hence a DNS lookup is used to identify the local host.
As the webpage is not cached and therefore must be found before the file can be requested and then received by the contacting host.
It is given that visits to “n” DNS servers to find the site occur a round-trip time (RTT) which adds up to “RTT1, RTT2,… RTTn” ,in which the numbers of RTT represents the DNS number.
- Therefore the total time it takes for the host to obtain the IP address can be denoted as: “RTT1+RTT2+RTT3+…RTTn”.
Given Data:
The HTML file references eight very small objects on the same server.
To Find:
Non Persistent HTTP with browser configured for 5 parallel connections:
c)
Program Plan Intro
DNS:
DNS stands for Domain Name System. It is the way that internet domain names are located and translated into internet protocol address.
TCP:
TCP stands for Transmission Control Protocol which is a standard that establishes and maintain a network conversion with the use of application programs.
Round Trip Time (RTT):
The length of time it takes for a signal to be sent along with the length of time to be acknowledged is called the round trip time.
There are “n” DNS servers in the connection.
Amount of elapsed time:
While clicking on a link to open a web page, the IP address of the associated web page is not cached in the local host and hence a DNS lookup is used to identify the local host.
As the webpage is not cached and therefore must be found before the file can be requested and then received by the contacting host.
It is given that visits to “n” DNS servers to find the site occur a round-trip time (RTT) which adds up to “RTT1, RTT2,… RTTn” ,in which the numbers of RTT represents the DNS number.
- Therefore the total time it takes for the host to obtain the IP address can be denoted as: “RTT1+RTT2+RTT3+…RTTn”.
Given Data:
The HTML file references eight very small objects on the same server.
To Find:
Persistent HTTP:
Expert Solution & Answer
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Students have asked these similar questions
Consider a web page, which contains 6 objects. How many RTTS does it take to download all
objects in this web page:
(a) Using non-persistent HTTP
(b) Using persistent HTTP without pipelining
(c) Using persistent HTTP with pipelining.
Download delays for 100 objects (HTTP 1.1 with browser caching). Consider an
HTTP 1.1 client and server. The RTT delay between the client and server is 2 seconds.
Suppose the time a server needs to transmit an object into its outgoing link is 3
seconds, as shown below for the first of these 100 requests.
initiate TCP
connection
RTT
request file
RTT
file received
time
You can assume that any other HTTP message not containing an object sent by the
client and server has a negligible (zero) transmission time. Suppose the client makes
100 requests, one after the other, waiting for a reply to a request before sending the
next request.
352 secs
Using HTTP 1.1, how much time elapses between the client transmitting the first
request, and the receipt of the last requested object, assuming the client uses the IF-
MODIFIED-SINCE header line, and 50% of the objects requested have not changed since
the client downloaded them (before these 100 downloads are performed)?
350 secs
252 secs
time to…
Question 23
A client's browser sends an HTTP request to a website. The website responds with a handshake and
sets up a TCP connection. The connection setup takes 2.1 ms, including the RTT. The browser then
sends the request for the website's index file. The index file references 8 additional images, which
are to be requested/downloaded by the client's browser.
Assuming all other conditions are equal, how much longer would non-persistent HTTP take than
persistent HTTP? (Give answer in milliseconds, without units, rounded to one decimal place. For an
answer of 0.01005 seconds, you would enter "10.1" without the quotes.)
Chapter 2 Solutions
EBK COMPUTER NETWORKING
Ch. 2 - List five nonproprietary Internet applications and...Ch. 2 - Prob. R2RQCh. 2 - Prob. R3RQCh. 2 - Prob. R4RQCh. 2 - Prob. R5RQCh. 2 - Prob. R6RQCh. 2 - Prob. R7RQCh. 2 - Prob. R8RQCh. 2 - Prob. R9RQCh. 2 - Prob. R10RQ
Ch. 2 - Why do HTTP, SMTP, and POP3 run on top of TCP...Ch. 2 - Prob. R12RQCh. 2 - Prob. R13RQCh. 2 - Prob. R14RQCh. 2 - Prob. R15RQCh. 2 - Prob. R16RQCh. 2 - Prob. R17RQCh. 2 - From a users perspective, what is the difference...Ch. 2 - Prob. R19RQCh. 2 - Prob. R20RQCh. 2 - Prob. R21RQCh. 2 - Prob. R22RQCh. 2 - Prob. R23RQCh. 2 - Prob. R24RQCh. 2 - Prob. R25RQCh. 2 - In Section 2.7, the UDP server described needed...Ch. 2 - Prob. R27RQCh. 2 - Prob. P1PCh. 2 - Prob. P2PCh. 2 - Prob. P3PCh. 2 - Prob. P4PCh. 2 - Prob. P5PCh. 2 - Prob. P6PCh. 2 - Prob. P7PCh. 2 - Prob. P8PCh. 2 - Prob. P9PCh. 2 - Prob. P10PCh. 2 - Prob. P11PCh. 2 - Prob. P13PCh. 2 - Prob. P14PCh. 2 - Prob. P15PCh. 2 - Prob. P16PCh. 2 - Prob. P17PCh. 2 - Suppose you can access the caches in the local DNS...Ch. 2 - Prob. P21PCh. 2 - Prob. P22PCh. 2 - Prob. P23PCh. 2 - Prob. P25PCh. 2 - Prob. P26PCh. 2 - Prob. P27PCh. 2 - Prob. P28PCh. 2 - Prob. P29PCh. 2 - Prob. P30PCh. 2 - Prob. P31PCh. 2 - Prob. P32P
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