CS732 Local Area Networks                         Midterm
Dr. Levine                                        March 5, 1996

               Answer questions to total up to 100 pts

Questions 1- 5 10 pts each

1) You are installing a small local area network in your company. 
You are allocated a budget of $25000 to buy 25 client machines for
a single room and $30000 to buy a server(s), printer(s), cables,
NICs, a network operating system, etc.  What equipment will you
choose?

2) Describe (at least) three different types of LAN topologies. Use
about one page.  

3) Describe three different types of IEEE 802.x media access
methods.  Use about one page for each.

4) For the IEEE LANs above, explain the topologies and give
examples of the media for which they are standardized.

5) Describe (at least) three different types of LAN mediums. Use
one or two pages.


Questions 6 - 18    5 pts each

6) Ethernet uses the medium access method of
   a) token passing
   b) polling
   c) carrier sense multiple access with collision avoidance
   d) carrier sense multiple access with collision detection
   e) synchronous time division multiplexing

7) An advantage of digital transmission over analog transmission is
that
a) transmission errors are not cumulative in digital transmission
b) transmission errors are not cumulative in analog transmission
c) digital signals can propagate further without the use of
repeaters or amplifiers than can analog signals
d) digital signals allow the use of FDM
e) digital transmission can be used for analog or digital
information, while analog transmission can be used only for analog
information

8) The ISO reference model for network architecture does not
include a
a) physical layer
b) medium access layer
c) network layer
d) transport layer
e) application layer
 
9) Typically a service primitive of protocol_layer_data.request is
sent
a) between peer protocols
b) from an nth layer protocol to its adjacent lower protocol
c) from an nth layer protocol to its adjacent upper protocol
d) from an nth layer protocol to the application layer
e) from the application layer to the nth layer protocol

10) A data link layer must provide the following function
a) frame synchronization
b) error recovery
c) sequencing
d) flow control
e) connection establishment

11) MAC addressing
a) typically provides an SSAP and DSAP
b) typically provides one octet for source and destination machines
c) is extendible to accommodate internetworking
d) typically provides for group and broadcast messages
e) always assigns unique hardwired values

12) A MAU is typically installed in
a) the host machine in CSMA/CD using category 5 twisted pair
b) the host machine in CSMA/CD using category 3 twisted pair
c) the hub using 75-ohm coaxial cable
d) the hub using 50-ohm coaxial cable
e) the hub using UTP

13) The advantages of standardizing protocols include
a) there are only a few organizations that issue standards, and
therefore standards are easy to define
b) once standards are defined, they always represent the most
current technology
c) standards facilitate the interconnection of diverse equipment
from different vendors
d) all companies and countries adhere to these standards
e) standards usually define the most efficient technologies

14) The only layer that directly connects to the transmission
medium is the
a) transmission layer
b) medium access layer
c) network layer
d) physical layer
e) device drivers

15) The control field in the LLC header of connectionless service
provides for the following types of frames
a) information 
b) unnumbered information
c) connection establishment (SABME)
d) supervisory frames
e) IEEE 802.3

16) A NIC typically
a) implements software functions
b) can be substituted for another type of NIC without changing the
higher layer protocols
c) is installed in a hub
d) implements clearly differentiated MAC and physical layer
functions
e) implements only MAC functions 
f) implements only physical layer functions

17) The most amount of wiring cable in required in a
a) bus physical topology
b) ring physical topology
c) star physical topology
d) tree physical topology
e) controller/terminal topology

18) The purpose of Manchester encoding is to provide for
a) frame synchronization
b) bit scrambling
c) clock synchronization
d) error recovery
e) high bit rate