单选题Which of the following should be configured to provide priority to voice traffic?（）A Port mirroringB DMZC QosD Trunking

第1题：

Which three QoS mechanisms can be configured to improve VoIP quality on a converged  network？（）

• A、The use of a queuing method that will give VoIP traffic strict priority over other traffic  
• B、The use of RTP header compression for the VoIP traffic.
• C、The proper classification and marking of the traffic as close to the source as possible
• D、The use of 802.1QinQ trunking for VoIP traffic
• E、The use of WRED for the VoIP traffic

第2题：

You have configured voice VLANs on Catalyst switch R1.  Which two statements are true about the  operation of voice VLANs on this device？ （）

• A、 When the voice VLAN feature is enabled， all untagged traffic is sent according to the default  CoS priority of the port.
• B、 Enabling voice VLANs enables the switch to create multiple queues for traffic that is entering a  port.
• C、 When voice VLANs are configured on a trunk link， UplinkFast must also be enabled.
• D、 Voice VLANs are configured to enable the switch to forward frames marked with the proper  CoS values over separate physical links.
• E、 Enabling voice VLANs enables the switch to forward frames with a specific 802.1P marking.

第3题：

第4题：

Which three statements are true about the voice VLAN feature on a Catalyst 2950 switch？ （Choose  three.）（）  

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

第5题：

You need to configure a new Company Catalyst 3560 switch for a VOIP-enabled office.  Which  three statements are true about the voice VLAN feature on this switch？（）

• 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

第6题：

What does the interface subcommand switchport voice vlan 222 indicate？（）

• A、The port is configured for both data and voice traffic.
• B、The port is fully dedicated to forwarding voice traffic.
• C、The port will operate as an FXS telephony port.
• D、Voice traffic will be redirected to VLAN 222.

第7题：

Which two statements are true about voice VLANs？（）

• A、Voice VLANs are only used when connecting an IP phone and a host to distinct switch ports
• B、Access ports that are configured with voice VLANs will always trust the CoS that is received from IP phones
• C、Access ports that are configured with voice VLANs may or may not override the CoS value that is received from an IP phone
• D、Voice VLANs are configured using the switchport voice vlan vlan-ID interface configuration command
• E、Voice VLANs provide a trunking interface between an IP phone and an access port on a switch to allow traffic from multiple devices that are connected to the port
• F、Enabling Voice VLAN on a switch port will automatically configure the port to trust the incoming CoS markings

第8题：

第9题：

Each port that is configured to use LACP has an LACP port priority. Which statements are true about LACP port priority？ （）

• A、 Port priority value can be configured between 1 and 65535.
• B、 A higher port priority value means a higher priority of LACP.
• C、 Port priority can be configured so that specific links can be chosen as active links rather than the hot standby links within the port channel.
• D、 LACP uses the port priority with the port number to form the port identifier.
• E、 LACP Port priority default value should always be changed

第10题：

When you enable port security on an interface that is also configured with a voice VLAN，  what is the maximum number of secure MAC addresses that should be set on the port？（）

• A、No more than one secure MAC address should be set.
• B、The default will be set.
• C、The IP phone should use a dedicated port， therefore only one MAC address is needed per port.
• D、No value is needed if the switchport priority extend command is configured. 
• E、No more than two secure MAC addresses should be set.