The core Company switches are configured to use 802.1Q trunks.  Which three statements are  correct with regard to the IEEE 802.1Q standard？（）

A . VTP mode B . VTP password C . VTP revision number D . VTP pruning E . VTP domain name F . None of the other alternatives apply

A . The default CoS value for incoming traffic is set up to 0. B . The CoS value is trusted for 802.1p or 802.1q tagged traffic. C . PortFast is automatically disabled when a voice VLAN is configured. D . The voice VLAN feature is disabled by default. E . The IP phone accepts the priority of all tagged and untagged traffic and sets the CoS value to 4. F . When the voice VLAN feature is enabled， all untagged traffic is sent according to the default  CoS priority of the port

A .  switchport access vlan vlan-id B .  switchport C .  switchport mode access D .  no switchport E .  None of the other alternatives apply

A . port-based RADIUS B . 802.1q trunking C . inline power D . protected port

A .  It tags the data frame with VLAN information and recalculates the CRC value B .  It encapsulates the data frame with a new header and frame check sequence C .  It modifies the port index of a data frame to indicate the VLAN D .  It adds a new header containing the VLAN ID to the data frame E .  None of the other alternatives apply

A .  It enables a PVST+ instance of 10 for vlan 11 and vlan 12 B .  It enables vlan 11 and vlan 12 to be part of the MST region 10 C .  It maps vlan 11 and vlan 12 to the MST instance of 10. D .  It creates an Internal Spanning Tree （IST） instance of 10 for vlan 11 and vlan 12   E .  It create a Common Spanning Tree （CST） instance of 10 for vlan 11 and vlan 12 F .  It starts two instances of MST， one instance for vlan 11 and another instance for vlan 12.

A .  Configure the switch to insert and remove DHCP relay information （option-82 field） in forwarded  DHCP request messages. B .  Configure DHCP snooping globally. C .  Configure the switch as a DHCP server. D .  Configure DHCP snooping on an interface. E .  Configure all interfaces as DHCP snooping trusted interfaces. F .  Configure DHCP snooping on a VLAN or range of VLANs.

A . It does not prune traffic from VLANs that are pruning-ineligible B . VLAN 1 is always pruning-eligible C . It will prune traffic from VLANs that are pruning-ineligible D . VLAN 2 is always pruning-ineligible E . None of the other alternatives apply

A . A root VTP server B . A trunk port C . VTP priority D . VLAN 1 E . None of the other alternatives apply

A .  Access B .  No negotiate C .  Trunk D .  Dynamic desirable E .  Dynamic auto F .  None of the other alternatives apply

A .  To verify the MST configuration， the show pending command can be used in MST configuration  mode. B .  When RSTP and MSTP are configured； UplinkFast and BackboneFast must also be enabled. C .  All switches in the same MST region must have the same VLAN-to-instance mapping， but  different configuration revision numbers. D .  All switches in an MST region， except distribution layer switches， should have their priority  lowered from the default value 32768. E .  An MST region is a group of MST switches that appear as a single virtual bridge to adjacent  CST and MST regions. F .  Enabling MST with the "spanning-tree modemst" global configuration command also enables  RSTP.

A . The CoS is trusted for 802.1P or 802.1Q tagged traffic. B . PortFast is disabled on the port. C . Port Security is automatically enabled on a voice VLAN port. D . Untagged traffic is sent according to the default CoS priority of the port. E . None of the other alternatives apply

A . It disables the trust boundary feature because the switch knows a Cisco IP phone is attached. B . The switch assigns a CoS value of 5 to incoming packets. C . If a Cisco IP phone is attached and removed， the switch continues to trust the CoS values as  long as the switch is not rebooted. D . It turns on STP to see if a Cisco IP phone is attached. E . If a Cisco IP phone is attached， the switch trusts the CoS. F . None of the other alternatives apply.

A . VLAN membership of a user always remains the same even when he/she is moved to another  location. B . VLAN membership of a user always changes when he/she is moved to another location. C . Membership can be static or dynamic. D . Membership can be static only. E . None of the other alternatives apply.

A .  virtualization B .  unified I/O C .  support for 48-port Gb/s line card D .  support for Data Center Service Modules E .  high performance F .  high availability

A . port-based radius B . 802.1q trunking C . inline power D . protected port

A .  A Catalyst switch cannot have ISL and IEEE 802.1q trunks enabled. B .  All Catalyst switches support ISL trunking. C .  A Catalyst switch will report giants if one side is configured for ISL while the other side is not. D .  ISL trunking requires that native VLANs match. E .  None of the other alternatives apply

A . VTP messages will not be forwarded over nontrunk links. B . VTP domain names need to be identical. However，case doesn’t matter. C . A VTP enabled device which receives multiple advertisements will ignore advertisements with higher configuration revision numbers. D . A device in "transparent" VTP v.1 mode will not forward VTP messages. E . VTP pruning allows switches to prune VLANs that do not have any active ports associated with  them.

A .  It can be used between Cisco and non-Cisco switch devices. B .  It calculates a new CRC field on top of the existing CRC field. C .  It adds 4 bytes of protocol-specific information to the original Ethernet frame. D .  It adds 30 bytes of protocol-specific information to the original Ethernet frame.

A .  The trunk link belongs to a specific VLAN. B .  Multiple trunk links are used to connect multiple end user devices. C .  A trunk link only supports native VLAN. D .  Trunk links use 802.10 to identify a VLAN. E .  The native VLAN of the trunk link is the VLAN that the trunk uses for untagged packets.

A .  DAI can be performed on ingress ports only. B .  DAI can be performed on both ingress and egress ports. C .  DAI is supported on access ports， trunk ports， EtherChannel ports， and private VLAN ports.   D .  DAI should be enabled on the root switch for particular VLANs only in order to secure the ARP  caches of hosts in the domain. E .  DAI should be configured on all access switch ports as untrusted and on all switch ports connected to other switches as trusted. F .  DAI is supported on access and trunk ports only.

A .  Causes the interface to apply ISL framing for traffic on VLAN 7 B .  Configures the trunking interface to forward traffic from VLAN 7 C .  Configures the interface to be a trunking port and causes traffic on VLAN 7 to be 802.1q tagged D .  Configures the trunking interface to send traffic from VLAN 7 untagged E .  None of the other alternatives apply

A .  CompanySwitch（config-if）#switchport trunk encapsulation dot1q B .  CompanySwitch（config-if）#switchport trunk encapsulation itef C .  CompanySwitch（config-if）#switchport trunk encapsulation fddi D .  CompanySwitch（config-if）#switchport trunk encapsulation isl E .  None of the other alternatives apply