Chapter 3 Practice Test Answers
1.
A. 4; B. 2; C. 5; D. 3; E. 1
2.
A and D. The Data Link layer of the OSI Model is divided into two separate
sublayers: Media Access Control (MAC) and Logical Link Control (LLC).
3.
C. The LLC acts as an interface between the MAC sublayer and the Network
layer by managing the frames.
4.
D. Since it has no error checking or controls to monitor the flow of information,
connectionless communication tends to be fastest.
5.
B. Connection-oriented mode is slower than connectionless mode; however, it is a
more reliable method of communication.
6.
A. Ethernet uses the CSMA/CD access method, which provides rules concerning
how stations communicate while sharing a common cabling system.
7.
C. The term “Ethernet” originally referred to network standards developed by
Digital, Intel, and Xerox; therefore, it is occasionally called the DIX standard.
8.
C. A variant of CSMA/CD is Carrier Sense Multiple Access with Collision
Avoidance (CSMA/CA). Instead of detecting collisions and resending later, CSMA/CA
attempts to completely avoid the collisions.
9.
A. Token Ring, or token passing, networks use a special type of data packet
known as a token. A single token travels around the ring from computer to computer.
10.
D. Although token passing networks use a ring topology, it is a logical ring.
Physically, they are wired as a star.
11.
C. Token Ring networks support a data transfer rate up to 16Mbps.
12.
B. In a FDDI network layout, a pair of fiber-optic rings connects each device.
Each ring contains a single token and the tokens travel in opposite directions between the
devices. If a break or other problem occurs in the primary ring, the secondary ring acts as
a backup, ensuring that data continues to move on the network.
13.
A. Since FDDI networks are fault tolerant and support high data transmission
speeds, they are commonly used as network backbones.
14.
B. The development of 100Base-TX Ethernet is taking the place of FDDI.
15.
D. The Physical layer handles the actual data transmission duties between
devices.
16.
B. Wireless LANs use the Carrier Sense Multiple Access with Collision
Avoidance (CSMA/CA) access method.
17.
B. The 802.11b standard boosted wireless network speeds to 11Mbps.
18.
C. A network meeting FDDI standards can extend to distances up to 60 miles.
19.
D. Network communications within the LLC sublayer work exactly the same on
all network topologies. In general, the LLC provides an interface between the protocols
(IPX/SPX, TCP/IP) being used on the network and the type of network (Ethernet, Token
Ring).
20.
A. The 802.2 standard defines how network communications should take place
within the LLC sublayer.