Chapter 11: Local Area Networks Key
1. Most types of LANs can accommodate up to 100 users.
2. LANs are always privately owned.
3. Another word for topology is configuration.
4. A LANs physical topology is the same as its logical topology.
5. One advantage of a star configuration is that if one cable connection fails, the other connections continue
operating.
6. If a LAN was physically wired as a ring, in which cables run between subsequent devices rather than to a
central hub, a failure in any cable connection would adversely affect the entire network.
7. Physical topology describes how network nodes are connected within the LAN.
8. The logical topologydictates how packets flow among the nodes of a LAN.
9. In a logical ring topology, packets flow sequentially from one computer to the next in a hub and spoke
pattern.
10. In a logical bus configuration, packets flow in an orderly sequence from node to node.
11. In a logical star topology, packets flow from a computer to a centralized node and then to another computer
in a hub-and-spoke pattern
12. Historically, the two most common access control procedures for shared LAN approaches have been token
passingand CSMA/CD.
13. Token passing access method is non-deterministic.
14. Using the token passing method, each node communicates only during its specified turn.
15. CSMA/CD is a deterministic access method.
16. With CSMA/CD, any device may transmit information at any given moment, provided no other devices are
already transmitting.
17. With CSMA/CD, packets are transmitted simultaneously to all nodes of the network.
18. In CSMA/CD, devices must possess a token to transmit packets to other nodes.
19. In some LANs, such as wireless LANs, collisions cannot be detected.
20. In CSMA/CA, if the transmitting node detects that the network is not idle, it waits a brief time before
starting the procedure again.
21. Latency becomes a problem in a shared CSMA/CD network if it has too many networked devices.
22. Ethernet LANs are always wired and never wireless.
23. The Ethernet preamble is the byte 10101010 repeated seven times, followed by 10101011.
24. Two other types of LANs, token ring and FDDI, have waned in popularity compared with Ethernet and
wireless LANs.
25. Token ring uses the CSMA/CD access method.
26. Wi-Fi requires formal licensing through the Federal Communications Commission (FCC)
27. Wi-Fi uses a carrier radio frequency in the 2.4-GHz or 5-GHz range.
28. IEEE 802.11g is not backward compatible with 802.11b.
29. IEEE 802.11b is a Wi-Fi wireless technology which operates at a frequency of 2.4 GHz.
30. Wireless LANs provide higher security than wired LANs.
31. As long as hackers are in range of a wireless access point, they can intercept signals that are not adequately
encrypted.
32. The most popular type of LAN is called:
33. A network that spans a confined geographical distance, such as a building or home, is called a:
34. A network which spans a larger geographical area, such as a city, nation, or the world at large is called a:
35. A computer user in a professional office requires shared access to a variety of local resources, including:
36. Devices on a network are sometimes called:
37. How network nodes are physically connected to each other is called the:
38. A network topology that employs a central node that all other nodes in the network are connected to is
called:
39. A physical topology in which the cable runs are laid out like spokes of a wheel is called:
40. A possible logical topology for a LAN is the:
41. If the LAN is physically wired as a star but uses a logical ring topology, it is often called:
42. An access method in which each network node is given a predetermined, orderly, and sequential opportunity
43. In CSMA/CD, a node starts to transmit:
44. 48-bit Ethernet addresses are usually written on NICs in which of the following numbering systems?
45. How many hexadecimal characters can act as shorthand for a 48-bit Ethernet address.
46. The hex character “C” is equal to the binary number:
47. Which standards body allocates a unique NIC identifier to each manufacturer?
48. Ethernet is implemented over:
49. Wireless Ethernet LANs use:
50. An Ethernet address is usually how many bits long?
51. Each Ethernet frame contains how many bytes of overhead?
52. Token ring is historically associated with what company?
53. An FDDI LAN uses which access method?
54. An FDDI LAN uses which logical topology?
55. An FDDI LAN uses which transmission medium?
56. An example of a Wi-Fi standard includes:
57. LAN is short for _________________________.
58. PAN is short for ____________________.
59. WAN is short for ____________________.
60. MAN stands for _________________________.
61. CAN stands for ________________________.
62. SAN stands for _________________________.
63. A token is defined as a signal that comprises a specific ________________________.
64. CSMA/CD stands for ____________________________________________________.
65. CSMA/CA stands for ____________________________________________________.
66. An access method is called ____________________ when you cannot determine beforehand how long data
may take to reach its destination.
67. Using CSMA/CA, a node that has information to transmit first listens to the network to see if another node
is transmitting. If the node finds that the network is idle, it sends a ____________________ packet to other
nodes.
68. Using CSMA/CA, if a node wants to give the ok to another device to send a packet, it can send a
____________________ to the other device.
69. Collisions on a CSMA/CD LAN occur when two or more nodes transmit ____________________.
70. Within the context of computer networking, latency is defined as the ____________________ between the
transmission and reception of packets over a network.
71. A LAN contains a range of hardware and physical media, including a ______________________________
transmission media, wiring hubs, high-speed switches, routers, and servers.
72. The original transmission medium that supported Ethernet was ____________________.
73. In an Ethernet frame, a series of eight bytes that identifies (or flags) the transmission as an Ethernet
transmission, helps achieve synchronization between devices, and indicates the start of transmission, is called
the ____________________.
74. Extra bytes added to an Ethernet frame or other frame format to bring the byte length of the frame to the
minimal required length are called ____________________.
75. Everything transmitted that is superfluous to the bytes of actual content within an Ethernet frame is called
____________________.
76. Wi-Fi stands for _____________________.
77. WLAN stands for ______________________________.
78. WiMAX is more formally called the IEEE ____________________ standard.
79. The IEEE 802.11i Wi-Fi standard addresses ____________________ mechanisms.
80. A device that connects wireless computers to a wired network to enable high-speed Internet access and other
services, is sometimes called a WAP, or ______________________.
81. The main advantages of wireless LANs are _________________________.
82. Devices connected to a network are called ____________________.
83. Why are networks classified into such categories as LANs, WANs, and MANs?
84. What is the difference between a LAN’s physical topology and logical topology?
85. Why do LANs require an access control mechanism?
86. What does it mean for an access mechanism to be deterministic?
87. Using CSMA/CD, what happens if two devices simultaneously determine that the LAN is available and
both begin to transmit information?
88. What is LAN switching?
89. What is a NIC?
90. Why is an Ethernet address written in hexadecimal?
91. Describe some functions of a LAN operating system, also called a network operating system.
92. What is a frame?
93. Discuss the merits of municipal wireless networks.
94. What is a rogue access point?
95. What is Ethernet switching?