1. (40%) Provide concise and straight answers to the following questions.
a. What are the key elements of telegraph network architecture?
b. Why is statistical multiplexing used in data networks?
c. What are the benefits of the layered architecture?
d. What is the purpose of network layer?
e. What are the fundamental differences between connection-oriented and
f. What are the two general approaches to send information faster?
g. What are the benefits of digital transmission?
h. What are the factors to be considered for selecting a line coding scheme?
i. What are the main characteristics of QAM?
j. Why does link layer typically use polynomial coding for error detection?
2. (20%) The Internet below consists of three LANs interconnected by two routers.
Assume that the hosts and routers have the IP addresses as shown.
a. Suppose that all traffic from network 3 that is destined to H1 is to be
routed directly through router R2 and that all other traffic from network 3
is to go to network 2. What routing table entries should be present in the
network 3 hosts and in R2?
b. Suppose that all traffic from network 1 to network 3 is to be routed
directly through R2. What routing table entries should be present in the
network 1 hosts and in R2?
本网站支持淘宝 支付宝 微信支付 paypal等等交易。如果不放心可以用淘宝交易！
E-mail: firstname.lastname@example.org 微信:itcsdx