LAN Switching Technologies - 2

drepitts8's version from 2016-02-04 02:23

Section 1

Question Answer
What are the possible trunking modes for a switch port? auto, on, desirable
What value is primarily used to determine which port becomes the root port on each non-root switch in a spanning-tree topology?Path cost
Which two protocols are used by bridges and/or switches to prevent loops in a layer 2 network?802.1d, STP
Which two of these are characteristics of the 802.1Q protocol? It modifies the 802.3 frame header and thus requires that the FCS be recomputed. It is a trunking protocol capable of carrying untagged frames.
Native VLANis supported in 802.1Q encapsulation only
IEEE 802.1Quses an internal tagging mechanism that inserts a four-byte tag field into the original Ethernet (802.3) frame between the Source Address and Type or Length fields.

Section 2

Question Answer
Which Cisco Catalyst feature automatically disables the port in an operational PortFast upon receipt of a BPDU?BPDU Guard
What is the function of the command "switchport trunk native vlan 999" on a Cisco Catalyst switch?It designates VLAN 999 for untagged traffic.
Which port state is introduced by Rapid-PVST?Discarding
A network administrator creates a layer 3 EtherChannel, bundling four interfaces into channel group 1. On what interface is the IP address configured?the port-channel 1 interface
A workgroup switch is configured with all ports assigned to VLAN2. In addition, all ports are configured as full-duplex FastEthernet. What is the effect of adding switch ports to a new VLAN on this switch?An additional broadcast domain will be created.
Which three elements must be used when you configure a router interface for vlan trunking?One IP network or subnetwork for each subinterface. Subinterface encapsulation identifiers that match vlan tags. One subinterface per vlan.

Section 3

Question Answer
In which circumstance are multiple copies of the same unicast frame likely to be transmitted in a switched LAN?in an improperly implemented redundant topology
What are the advantages of using VLANs?They allow logical grouping of users by function. They can enhance network security. They increase the number of broadcast domains while decreasing the size of the broadcast domains.
VLANmakes up a switched network that is logically segmented by functions, project teams, or applications, without regard to the physical location of users.
Which three statements about RSTP are true?RSTP significantly reduces topology reconverging time after a link failure. RSTP expands the STP port roles by adding the alternate and backup roles. RSTP provides a faster transition to the forwarding state on point-to-point links than STP
A router has two FastEthernet interfaces and needs to connect to four vlans in the local network. How can you accomplish this task, using the fewest physical interfaces and without decreasing network performance?Implement a router-on-a-stick configuration.
Three switches are connected to one another via trunk ports. Assuming the default switch configuration, which switch is elected as the root bridge for the spanning-tree instance of VLAN 1?The switch with the lowest MAC address

Section 4

Question Answer
TrunkingA trunk connection is a link that carries VLAN information between VLAN-aware Layer 2 devices.
What is one benefit of PVST+PVST+ allows the root switch location to be optimized per VLAN.
Rapid PVST+is the IEEE 802.1w (RSTP) standard implemented per VLAN.
Which statement about vlan operation on Cisco catalyst switches is true?Unknown unicast frames are retransmitted only to the ports that belong to the same vlan.
Which two benefits are provided by creating VLANs?added security, provides segmentation
Assuming the default switch configuration, which VLAN range can be added, modified and removed on a Cisco switch?2 through 1001

Section 5

Question Answer
Which three of these statements regarding 802.1Q trunking are correct?802.1Q native VLAN frames are untagged by default. 802.1Q trunks can use 10 Mb/s Ethernet interfaces. 802.1Q trunks should have native VLANs that are the same at both ends.
Which three statements accurately describe layer 2 Ethernet switches? Microsegmentation decreases the number of collisions on the network. In a properly functioning network with redundant switched paths, each switched segment will contain one root bridge with all its ports in the forwarding state. All other switches in that broadcast domain will have only one root port. Establishing vlans increases the number of broadcast domains.
Which IEEE standard protocol is initiated as a result of successful DTP completion in a switch over FastEthernet?802.1Q
Which two of these statements regarding RSTP are correct?RSTP defines new port roles. RSTP is compatible with the original IEEE 802.1D STP.
RSTPRapid Spanning Tree Protocol
RSTP significantly reduces the time to reconverge the active topology of the network when changes to the physical topology or its configuration parameters occur.

Section 6

Question Answer
RSTP Port RolesRoot, Designated, Alternate, Backup, Disabled
Which two states are the port states when RSTP has converged?discarding, forwarding
RSTP port states discarding, learning, forwarding.
When RSTP has convergedevery port is either in discarding state or in forwarding state.
Which two link protocols are used to carry multiple VLANs over a single link?802.1q ISL
What are three benefits of implementing VLANs?A higher level of network security can be reached by separating sensitive data traffic from other network traffic. A more efficient use of bandwidth can be achieved allowing many logical networks to use the same network infrastructure. Broadcast storms can be mitigated by increasing the number of broadcast domains, thus reducing their size.
When PVST+ is in work on VLAN1 of the switch, what will affect on selection of one of the switches in the VLAN as root-bridge?Lowest MAC address

Section 7

Question Answer
Which protocol provides a method of sharing VLAN configuration information between switches?VTP
VTPVLAN Trunk Protocol
VLAN Trunk Protocol is a Cisco proprietary protocol, used to share VLAN configuration information between Cisco switches on trunk connections.
VTP allows switches to share and synchronize their VLAN information, which ensures that your network has a consistent VLAN configuration.
Which are valid modes for a switch port used as a VLAN trunk?Auto On Desirable
Auto Creates the trunk on the neighboring switch based on the request from the neighboring switch.
Desirable Communicates to the neighboring switch that the port is capable of being a trunk, and would like the neighboring switch to also be a trunk.
On DTP has spoken to the neighboring switch and automatically enables trunking regardless of the state of its neighboring switch.
Nonegotiate DTP has not spoken to the neighboring switch and automatically enables trunking on its port regardless of the state of its neighboring switch.
Offrunking is not allowed on this port regardless of the DTP mode configured on the other switch

Section 8

Question Answer
STPSpanning-Tree Protocol
Spanning-Tree Protocolimplements the 802.1d IEEE algorithm by exchanging BPDU messages with other switches to detect loops, and then removes the loop by shutting down selected bridge interfaces.
What are three advantages of VLANs?VLANs establish broadcast domains in switched networks. VLANs allow access to network services based on department, not physical location. VLANs can greatly simplify adding, moving, or changing hosts on the network.
Which three statements are typical characteristics of VLAN arrangements?Connectivity between VLANs requires a Layer 3 device. Each VLAN uses a separate address space. A switch maintains a separate bridging table for each VLAN
VLAN 3 is not yet configured on your switch. What happens if you set the switchport access vlan 3 command in interface configuration mode?The command is accepted and the respective VLAN is added to lan.dat.
At which layer of the OSI model is RSTP used to prevent loops?Data link

Section 9

Question Answer
Which two commands can be used to verify a trunk link configurationt status on a given cisco switch? show interfaces interface trunk show interfaces interface switchport
show interfaces trunkwill list all the interfaces that are currently trunking
show interfaces switchportwill show you the operational and administrative mode of each interface.
Switch ports operating in which two roles will forward traffic according to the IEEE 802.1w standard?designated root
Which term describes a spanning-tree network that has all switch ports in either the blocking or forwarding state?converged
What are two characteristics of a switch that is configured as a VTP client?The local vlan configuration is updated only when an update that has a higher configuration revision number is received. When switches in VTP client mode are rebooted, they send a VTP advertisement request to the VTP servers.