The use of ___ prevent any single machine from monopolizing the network's shared bus cable and makes the process of retransmitting lost data more efficient. (pg. 69)

A. segments

B. datagrams

C. packets

D. frames

D. Because of the benefits of shared access and more efficient retransmissions, all networking technologies use frames.

The ___ gives a receiving NIC time to realize a frame is coming and to know exactly where the frame starts. (pg. 70)

A. padding

B. frame check sequence

C. preamble

D. MAC address

C. The preamble is a 7-byte series of alternating ones and zeroes with a 1-byte start frame delimiter or an 8-byte series of alternating ones and zeroes. It always proceeds a frame. (pg. 70)

Padding is extra data to make sure a frame is at least 64 bytes.

MAC addresses, destination and source, are at the beginning of the frame. The frame check sequence (FCS is at the tail end of the frame.

True or false:

In a bus network, all the connected computers could see all traffic. (pg. 70)

The ___ in the frame enabled NICs to examine each frame and process only frames intended for them. The ___ in the frame enabled the recipient to respond accurately. (pg. 70)

A. destination address

B. data

C. source address

D. frame check sequence (FCS)

An Ethernet frame may carry one of several types of data. The ___ field helps the receiving computer interpret the frame contents at a very basic level. (pg. 70)

A. type

B. data

C. destination address

D. frame check sequence

A. Type

The data field carries the frame's contents.

The destination address field is how the frame is sent to the right recipient.

The frame check sequence enables Ethernet nodes to recognize when bad things happen to good data.

True or false:

The type field does not tell you if the frame carries higher-level data, such as an email message or Web page. (pg. 71)

The part of the frame that contains whatever payload the frame carries. (pg. 71)

A. type

B. segment

C. pad

D. data

D. Data. If the frame carries an IP packet, that packet will include extra information, such as the IP addresses of the source and destination systems.

Type and padding are parts of an Ethernet frame, but they don't contain the payload. A (TCP) segment is the connection-oriented payload of an IP packet that works at the Transport layer.

Extra data that a sending NIC may add to an Ethernet frame to bring the data up to the minimum 64 bytes in size. (pg. 71)

A. padding

B. packet

C. payload

D. preamble

A. If an Ethernet frame has fewer than 64 bytes of data to haul, the sending NIC automatically adds a pad as extra data.

Packets and payloads are placed into frames, but are critical parts of the frame.

A preamble comes before the frame.

The naming convention of an Ethernet cabling system like 10BASE-T can be broken down into three parts (pg. 72). What are the characteristics of these parts? (Choose three)

A. protocol                               D. speed

B. maximum distance               E. signaling type

C. cable type                            F.network type

D. The number refers to the speed (10 = 10 Mbps)

E. The word refers to the signaling type ("Base" = baseband)

C. The letter refers to the cable type (T = twisted pair)

What is the difference between broadband and baseband? Choose all that apply (pg. 72)

A. Signal type

B. Cost

C. Cable type

D. Number of signals

E. Data flow

All except C.:

Signal type: Broadband uses analog signals, while baseband uses digital signals.

Cost: Baseband is cheaper and simpler to implement than broadband.

Number of signals: Broadband can transmit multiple signals simultaneously, while baseband can only transmit one signal at a time. 

Data flow: In broadband, each channel transmits data in one direction, while baseband can send or receive data on the same wire.

True or False:

A 10BASE-T device that was connected to a hub can send and receive data simultaneously. (pg.74)

NICs that can only communicate in one direction at a time run in ___ mode. NICs that can send and receive at the same time run in ___ mode. (pg. 74)

A. synchronous                D. ad-hoc

B. asynchronous              E. full-duplex

C. half-duplex                  F. peer-to-peer

Orange/White, Orange, Green/White, Blue, Blue/White, Green, Brown/White, Brown

[image]

What is the difference between between the 568A and 568B cabling standards? (pg. 76)

Hint: "GO"

The green and orange pairs are swapped between them, where as the blue and brown pairs stay the same.

568A starts with green/white and green, while 568B starts with orange/white and orange.

The twisted pair cable connecting a computer to a hub in a 10BASE-T network couldn't exceed ___ meters in length, and the hub could connect no more than ___ computers. (pg. 76)

A. 100/1024

B. 100/10

C. 55/100

D. 10/6

A. The maximum distance between the hub and a node is 100 meters in a 10BASE-T network, and it can hold no more than 1024 nodes per hub.

Earlier Ethernet networks used a system called ___ to determine which computer should use a shared cable at a given moment. Each node using the network examined the cable before sending a data frame. (pg. 79)

A. CSMA/CD

B. CSMA/CA

C. full-duplex mode

D. half-duplex mode

A. Carrier-sense multiple access with collision detection (CSMA/CD) stops computers from sending information on the same ethernet wire at the same time. With this rule, a computer will check that the wire is not being used before it sends information.

CSMA/CA (collision avoidance) is primarily used in wireless networks because they are half-duplex.

Modern Ethernet networks primarily run in full-duplex mode so they don't need CSMA/CD, although it is still supported.

When two NICs on the same bus sent a frame at the same time, they'd detect a ___ and stop transmitting.

How did they decide which transmitted first? (pg. 80)

Collision

They would each generate a random number to determine how long to wait. The node with the lowest number would transmit first.

True or false:

Switches never repeat all incoming frames to all connected nodes like a hub would. (pg. 82)

Layer 2, Data Link

A switch filters traffic on MAC addresses, and MAC addresses run at Layer 2.