CCNA FOR YOU

Which of the following statements most accurately describes the characteristics of
the above networks broadcast and collision domains? (Select the two best answer
choices)
A. There are two broadcast domains in the network.
B. There are four broadcast domains in the network.
C. There are six broadcast domains in the network.
D. There are four collision domains in the network.
E. There are five collision domains in the network.
F. There are seven collision domains in the network.
Answer: A, F
Explanation:
In this network we have a hub being used in the Sales department, and a switch being
used in the Production department. Based on this, we have two broadcast domains: one
for each network being separated by a router. For the collision domains, we have 5
computers and one port for E1 so we have 6 collision domains total because we use a
switch in the Production Department so 5 are created there, plus one collision domain for
the entire Sales department because a hub is being used.


QUESTION NO: 4
LAN consists of one large flat network. You decide to
segment this LAN into two separate networks with a router. What will be the affect
of this change?
A. The number of broadcast domains will be decreased.
B. It will make the broadcasting of traffic between domains more efficient between
segments.
C. It will increase the number of collisions.
D. It will prevent segment 1's broadcasts from getting to segment 2.
E. It will connect segment 1's broadcasts to segment 2.
Answer: D
Explanation
A router does not forward broadcast traffic. It therefore breaks up a broadcast domain,
reducing unnecessary network traffic. Broadcasts from one segment will not be seen on
the other segment.
Incorrect Answers:
A. This will actually increase the number of broadcast domains from one to two.
B. All link level traffic from segment one to segment two will now need to be routed
between the two interfaces of the router. Although this will reduce the traffic on the LAN
links, it does also provide a less efficient transport between the segments.
C. Since the network size is effectively cut into half, the number of collisions should
decrease dramatically.
E. Broadcasts from one segment will be completely hidden from the other segment.


QUESTION NO: 5

Which of the following are benefits of segmenting a network with a router? (Select
all that apply)
A. Broadcasts are not forwarded across the router.
B. All broadcasts are completely eliminated.
C. Adding a router to the network decreases latency.
D. Filtering can occur based on Layer 3 information.
E. Routers are more efficient than switches and will process the data more quickly.
F. None of the above.

Answer: A, D
Explanation
Routers do not forward broadcast messages and therefore breaks up a broadcast domain.
In addition, routers can be used to filter network information with the use of access lists.
Incorrect Answers:
B. Broadcasts will still be present on the LAN segments. They will be reduced, because
routers will block broadcasts from one network to the other.
C. Adding routers, or hops, to any network will actually increase the latency.
E. The switching process is faster than the routing process. Since routers must do a layer
3 destination based lookup in order to reach destinations, they will process data more
slowly than switches.


QUESTION NO: 10
Given the choices below, which address represents a unicast address?
A. 224.1.5.2
B. FFFF. FFFF. FFFF.
C. 192.168.24.59/30
D. 255.255.255.255
E. 172.31.128.255/18
Answer: E
Explanation:
172.31.128.255 is the only unicast address. It seems to be a broadcast address, because of
255 in the last octet, the broadcast address for this network is 172.31.131.255.
Incorrect Answers:
A: 224.1.5.2 is a multicast address.
B: This is a broadcast layer 2 (data link) address.
C: Using a /30 for the subnet mask, this IP address becomes the broadcast address.
D. This is a broadcast IP address.


QUESTION NO: 11
With regard to bridges and switches, which of the following statements are true?
(Choose three.)
A. Switches are primarily software based while bridges are hardware based.
B. Both bridges and switches forward Layer 2 broadcasts.
C. Bridges are frequently faster than switches.
D. Switches typically have a higher number of ports than bridges.
E. Bridges define broadcast domain while switches define collision domains.
F. Both bridges and switches make forwarding decisions based on Layer 2 addresses.

Answer: B, E, F
Explanation:
B, F: Both are layer 2 (data link) devices designed to forward layer 2 broadcasts and
multicast addresses.
E: All hosts within a bridged network comprise a single broadcast domain, while switches
can be used to segment LANs into separate collision domains. Switches are
VLAN-capable while bridges are typically not capable of this.