EBK COMPUTER NETWORKING
7th Edition
ISBN: 8220102955479
Author: Ross
Publisher: PEARSON
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Question
Chapter 2, Problem P23P
a)
Program Plan Intro
Given Information:
Consider a distribution scheme in which the server sends the file to each client, in parallel, at a rate of a rate of us/N.
b)
Program Plan Intro
Given Information:
Consider a distribution scheme in which the server sends the file to each client, in parallel, at a rate of a rate of us/N.
c)
Program Plan Intro
Given Information:
A file of F bits to N peers using client-server architecture is present. A fluid model where the server can simultaneously transmit to multiple peers, transmitting to each peer at different rates, as long as the combined rate does not exceed us is also present.
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Consider sending a file of F bits over a path of Q links. Each link transmits at R bits per second
(bps). The network is lightly loaded so that there are no queueing delays. When a form of packet
switching is used, the F
bits are broken up into packets, each packet with L bits, of which h bits of it are header.
Propagation delay is
negligible. Let F = 5x104, Q = 20, R = 1 Mbps, L = 1000, and h = 10.
c. Suppose the network is a packet-switched virtual circuit network. Denote the VC set-up time
by ts = 250
milliseconds. How long does it take to send the file from source to destination?
Suppose that the average object size is 850,000 bits and that the average request rate from the institution’s browsers to the origin servers is 16 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 an HTTP request until it receives the response is three seconds on average (see Section 2.2.5). Model the total average response time as the sum of the average access delay (that is, the delay from Internet router to institution router) and the average Internet delay. For the average access delay, use Δ/(1 – Δ ), where Δ is the average time required to send an object over the access link and is the arrival rate of objects to the access link.
a. Find the total average response time.b. Now suppose a cache installed in the institutional LAN, Suppose the miss rate is 0.4. Find the total response time.
Copy from chegg == Report!
A communication line capable of transmitting at a rate of 50 Kbits/secwill be used to accommodate 10 sessions each generating Poisson traffic at a rate 150 packets/min.Packet length are exponentially distributed with mean 1000 bits.
For each session, find the averagenumber of packets in queue, the average number in the system, and the average delay per packetwhen the line is allocated to the sessions by using:
i) 10 equal-capacity time-division multiplexed channels;ii) statistical multiplexing
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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