Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

ICND1 > Building Ethernet LANs with Switches > Flashcards

Building Ethernet LANs with Switches Flashcards

1
Q

What does CSMA/CD stand for?

A

Carrier Sense Multiple Access with Collision Detection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

LAN switches receive Ethernet frames and then make a switching decision: either forward the frame out some other port(s) or ignore the frame. To accomplish this primary mission switches perform what three actions?

A
  1. Deciding when to forward a frame or when to filter (not forward) a frame, based on the destination MAC address.
  2. Learning MAC address by examining the source MAC address of each frame received by the switch.
  3. Creating a (Layer 2) loop-free environment with other switches by using Spanning Tree Protocol (STP)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Swithces build the address table by listening to incoming frames and examining the ______ ______ ______ in the frame.

A

source MAC address

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Switches keep a timer for each entry in the MAC address table, called an ______ ______.

A

inactivty timer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

When thers is no matching entry in the table, switches forward the frame out all interfaces (except the incoming interface) using a process called _________.

A

flooding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Spanning Tree Protocol causes each interface on a switch to settle into either a _______ state or a _______ state.

A

blocking or forwarding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

__________ means that the interface cannot forward or receive data frames

A

blocking

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

_________ means that the interface can send and receive data frames.

A

forwarding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

With _____-_____ processing, the switch starts sending the frame out the output port as soon as possiable.

A

cut-through

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

______-____ ______ works similarly to cut-through, but it tries to reduce the number of errored frames that it forwards.

A

Fragment-free processing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

The switch fully recieves all bits in the frame (store) before forwarding the frame (forward). This allows the switch to check the FCS before forwarding the frame.

A

Store-and-forward

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

The switch forwards the frame as soon as it can. This reduces latency but does not allow the switch to descard frames that fail the FCS check.

A

Cut-through

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

The switch forwards the frame after receving the first 64 bytes of the frame, thereby avoiding forwarding frames that were errored because of a collision.

A

Fragment-free

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are four benefits of using LAN switches?

A
  1. Switch ports connected to a single device microsegment the LAN, providing dedicated bandwidth to the single device.
  2. Switches allow multiple simultaneous conversations between devices on different ports.
  3. Switch ports connected to a single device support full-duplex, in effect doubling the amount of bandwidth available to the device
  4. Switches support rate adaptation, which means that devices that use different Ethernet speeds can communicate through the switch (hubs cannot)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Why do switches use STP?

A

Switches use STP to prevnet loops by causing some interfaces to block, meaning that they do not send or receive frames.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the logic that switches use to learn MAC address table entries:

A

a. For each received frame, examine the source MAC address and note the interface from which the frame was received.
b. If it is not already in the table, add the MAC address and interface it was learned on, setting the inactivity timer to 0.
c. If it is already in the table, reset the inactivity timer for the entry to 0

17
Q

A ________ _________ is a set of netowrk interface cards (NIC) for which a frame sent by one NIC could result in a collision with a frame sent by any other NIC in the same collision domain.

A

collision domains

18
Q

A ________ ________ is a set of NICs for which a broadcast frame sent by one NIC is received by all other NICs in the same broadcast domain

A

broadcast domain

19
Q

A _______ breaks LANs into multiple broadcast domains, but switches and hubs do not.

A

router

20
Q

A ______ consists of all devices in the same broadcast domain.

A

LAN

21
Q

The term _______ LAN refers to the LAN created to support larger buildings, or multiple buildings in somewhat close proximity to one another.

A

campus

22
Q

_______ switches connect directly to end users, providing user device access to the LAN.

A

Access

23
Q

_______ switches provide a path through which the access switches can forward traffic to each other.

A

Distribution

24
Q

Aggregates distribution switches in very large campus LANs, providing very high forwarding rates.

A

Core

25
Q

Which of the following statements describes part of the process of how a switch decides to forward a frame destined for a known unicast MAC address?

a. It compares the unicast destination address to the bridging, or MAC address, table.
b. It compares the unicast source address to the bridging, or MAC address, table.
c. It forwards the frame out all interfaces in the same VLAN except for the incoming interface.
d. It compares the destination IP address to the destination MAC address.
e. It compares the frames incoming to the source MAC entry in the MAC address table.

A

a. It compares the unicast destination address to the bridging, or MAC address, table.

26
Q

Which of the following statements describes part of the process of how a LAN switch decides to forward a frame destined for a broadcast MAC address?

a. It compares the unicast destination address to the bridgining, or MAC address, table.
b. It compares the unicast source address to the bridging, or MAC address, table.
c. It forwards the frame out all interfaces in the same VLAN except for the incoming interface.
d. It compares the destination IP address to the destination MAC address.
e. It compares the frames incoming to the source MAC entry in the MAC address table.

A

c. It forwards the frame out all interfaces in the same VLAN except for the incoming interface.

27
Q

Which of the following statements best describes what a switch does with a frame destined for an unknown unicast address?

a. it forwards out all interfaces in the same VLAN except for the incoming interface.
b. It forwards the frame out the one interface identified by the matching entry in the MAC address table.
c. It compares the destination IP address to the destination MAC address.
d. It compares the frame’s incoming interface to the source MAC entry in the MAC address table.

A

a. it forwards out all interfaces in the same VLAN except for the incoming interface.

28
Q

Which of the following comparisons does a switch make when deciding whether a new MAC address should be added to its MAC address table?

a. It compares the unicast destination address to the bridging, or MAC address, table.
b. It compares the unicast source address to the bridging, or MAC address, table.
c. It compares the VLAN ID to the bridging, or MAC address, table.
d. It compares the destination IP address’s ARP cache entry to the bridging, or MAC address, table.

A

b. It compares the unicast source address to the bridging, or MAC address, table.

29
Q

PC1, with MAC address 1111.1111.1111.1111, is connected to Switch SW1’s Fa0/1 interface. PC2, with MAC address 2222.2222.2222.2222, is connected to SW1’s Fa0/2 interface. PC3, with MAC address 3333.3333.3333.3333, connects to SW1’s Fa0/3 interface. The switch begins with no dynamically learned MAC addresses, followed by PC1 sending a frame with a destination address of 2222.2222.2222.2222. If the next frame to reach the switch is a frame sent by PC3, destined fro PC2’s MAC address of 2222.2222.2222.2222, which of the following are true? (choose two)

a. The switch forwards the frame out interface Fa0/1
b. The switch forwards the frame out interface Fa0/2
c. The switch forwards the frame out interface Fa0/3
d. The switch discards (filters) the frame.

A

a. The switch forwards the frame out interface Fa0/1

b. The switch forwards the frame out interface Fa0/2

30
Q

Which of the following devices would be in the same collision domain as PC1?

a. PC2, which is separated from PC1 by an Ethernet hub
b. PC3, which is separated from PC1 by a transparent bridge.
c. PC4, which is separated from PC1 by a Ethernet switch
d. PC5, which is separated from PC1 by a router

A

a. PC2, which is separated from PC1 by an Ethernet hub

31
Q

Which of the following devices would be in the same broadcast domain as PC1? (Choose Three)

a. PC2, which is separated from PC1 by an Ethernet hub
b. PC3, which is separated from PC1 by a transparent bridge.
c. PC4, which is separated from PC1 by a Ethernet switch
d. PC5, which is separated from PC1 by a router

A

a. PC2, which is separated from PC1 by an Ethernet hub
b. PC3, which is separated from PC1 by a transparent bridge.
c. PC4, which is separated from PC1 by a Ethernet switch

32
Q

Which of the following Ethernet standards support a maximum cable length of longer than 100 meters? (choose two)

a. 100BASE-T
b. 1000BASE-LX
c. 1000BASE-T
d. 100BASE-FX

A

b. 1000BASE-LX

d. 100BASE-FX

33
Q

A Cisco LAN switch connects to three PCs(PC1, PC2, PC3), each directly using a cable that supports Ethernet UTP speeds up through 1000 Mbps (1 Gbps). PC1 uses a NIC that supports only 10BASE-T, while PC2 has a 10/100 NIC, and PC3 has a 10/100/1000 NIC. Assuming that the PCs and switch use IEEE autonegotiation, which PCs will use half-duplex?

a. PC1
b. PC2
c. PC3
d. None of the PCs will use half-duplex

A

d. None of the PCs will use half-duplex

ICND1 (9 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions