QUESTION 11
What value is primarily used to determine which port becomes the root port on each nonroot switch in a spanning-tree topology?

A.    path cost
B.    lowest port MAC address
C.    VTP revision number
D.    highest port priority number
E.    port priority number and MAC address

Answer: A
Explanation:
The path cost to the root bridge is the most important value to determine which port will become the root port on each non-root switch. In particular, the port with lowest cost to the root bridge will become root port (on non-root switch).

QUESTION 12
What is the function of the command switchport trunk native vlan 999 on a Cisco Catalyst switch?

A.    It creates a VLAN 999 interface.
B.    It designates VLAN 999 for untagged traffic.
C.    It blocks VLAN 999 traffic from passing on the trunk.
D.    It designates VLAN 999 as the default for all unknown tagged traffic.

Answer: B
Explanation:
Configuring the Native VLAN for Untagged Traffic
A trunk port configured with 802.1Q tagging can receive both tagged and untagged traffic. By default, the switch forwards untagged traffic in the native VLAN configured for the port. The native VLAN is VLAN 1 by default.

QUESTION 13
Which two protocols are used by bridges and/or switches to prevent loops in a layer 2 network? (Choose two.)

A.    802.1d
B.    VTP
C.    802.1q
D.    STP
E.    SAP

Answer: AD
Explanation:
This question is to examine the STP protocol.
STP (802.1d) is used to prevent Layer 2 loops.
802.1q is a Frame Relay protocol which belongs to VLAN.
SAP is a concept of the OSI model.

QUESTION 14
Which switch would STP choose to become the root bridge in the selection process?

A.    32768: 11-22-33-44-55-66
B.    32768: 22-33-44-55-66-77
C.    32769: 11-22-33-44-55-65
D.    32769: 22-33-44-55-66-78

Answer: A

QUESTION 15
A switch is configured with all ports assigned to vlan 2 with full duplex FastEthernet to segment existing departmental traffic. What is the effect of adding switch ports to a new VLAN on the switch?

A.    More collision domains will be created.
B.    IP address utilization will be more efficient.
C.    More bandwidth will be required than was needed previously.
D.    An additional broadcast domain will be created.

Answer: D
Explanation:
Each VLAN creates its own broadcast domain. Since this is a full duplex switch, each port is a separate collision domain.

QUESTION 16
What are three benefits of implementing VLANs? (Choose three.)

A.    A higher level of network security can be reached by separating sensitive data traffic from other
network traffic.
B.    A more efficient use of bandwidth can be achieved allowing many physical groups to use the same
network infrastructure.
C.    A more efficient use of bandwidth can be achieved allowing many logical networks to use the same
network infrastructure.
D.    Broadcast storms can be mitigated by increasing the number of broadcast domains, thus reducing
their size.
E.    Broadcast storms can be mitigated by decreasing the number of broadcast domains, thus increasing
their size.
F.    VLANs make it easier for IT staff to configure new logical groups, because the VLANs all belong to
the same broadcast domain.
G.    Port-based VLANs increase switch-port use efficiency, thanks to 802.1Q trunks.

Answer: ACD
Explanation:
Benefits of VLANs
VLAN is a network structure which allows users to communicate while in different locations by sharing one multicast domain and a single broadcast. They provide numerous networking benefits and have become popular in the market. For instance, it helps reduce administrative costs when users are geographically dispersed.
1. Inexpensive
The popularity of VLANs is due to the fact that changes, adds, and moves can be attained simply by making necessary configurations on the VLAN port. Time-consuming, re-addressing, and host reconfigurations is now a thing of the past, because network configuration can be made at ease when need arises.
2. Better management
A VLAN typically solve the scalability issues that exist in a large network by breaking the main domain into several VLAN groups or smaller broadcast configurations, thereby encourage better control of multicast traffic as well as broadcast domains.
3. Improves network security
High-security can be positioned in different VLAN groups to ensure that non-members cannot receive their broadcasts. On the other hand, a router is added and workgroups relocated into centralized locations.
4. Enhances performance
A more efficient use of bandwidth can be achieved allowing many logical networks to use the same network infrastructure.
5. Segment multiple networks
VLANs are typically used to achieve multiple purposes. They are popularly used to reduce broadcast traffic. Each VLAN creates a separate, smaller broadcast domain.
6. Better administration
VLANs facilitate grouping of multiple geographical stations. When VLAN users move to another physical location, the network does not have to be configured.

QUESTION 17
Which IEEE standard protocol is initiated as a result of successful DTP completion in a switch over Fast Ethernet?

A.    802.3ad
B.    802.1w
C.    802.1D
D.    802.1Q

Answer: D
Explanation:
Dynamic Trunking Protocol (DTP) is a Cisco proprietary protocol for negotiating trunking on a link between two devices and for negotiating the type of trunking encapsulation (802.1Q) to be used.

QUESTION 18
Which of the following are benefits of VLANs? (Choose three.)

A.    They increase the size of collision domains.
B.    They allow logical grouping of users by function.
C.    They can enhance network security.
D.    They increase the size of broadcast domains while decreasing the number of collision domains.
E.    They increase the number of broadcast domains while decreasing the size of the broadcast domains.
F.    They simplify switch administration.

Answer: BCE
Explanation:
When using VLAN the number and size of collision domains remain the same -> VLANs allow to group users by function, not by location or geography -> . VLANs help minimize the incorrect configuration of VLANs so it enhances the security of the network -> .
VLAN increases the size of broadcast domains but does not decrease the number of collision domains ->
VLANs increase the number of broadcast domains while decreasing the size of the broadcast domains which increase the utilization of the links. It is also a big advantage of VLAN -> . VLANs are useful but they are more complex and need more administration ->

QUESTION 19
In an Ethernet network, under what two scenarios can devices transmit? (Choose two.)

A.    when they receive a special token
B.    when there is a carrier
C.    when they detect no other devices are sending
D.    when the medium is idle
E.    when the server grants access

Answer: CD
Explanation:
Ethernet network is a shared environment so all devices have the right to access to the medium. If more than one device transmits simultaneously, the signals collide and can not reach the destination.
If a device detects another device is sending, it will wait for a specified amount of time before attempting to transmit.
When there is no traffic detected, a device will transmit its message. While this transmission is occurring, the device continues to listen for traffic or collisions on the LAN. After the message is sent, the device returns to its default listening mode.

QUESTION 20
Which two states are the port states when RSTP has converged? (Choose two.)

A.    discarding
B.    listening
C.    learning
D.    forwarding
E.    disabled

Answer: AD
Explanation:
http://www.cisco.com/en/US/tech/tk389/tk621/technologies_white_paper09186a0080094cfa.shtml #states

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