A question-about voice LAN port. (Choose three.)
A. Voice needs their own VLAN
B. Traffic tagged or untagged
C. Interface should be trunk or access
D. QoS works with QoS queue if the port state is set to trust
E. Port must be untrust
F. Port must be trust
I think the correct ans are : A, B, & D?.
A. Voice needs their own VLAN
B. Traffic tagged or untagged
D. QoS works with QoS queue if the port state is set to trust
A. Voice use separate vlan and it is called auxilary vlan or voice vlan
B -> In the access VLAN tagged with a Layer 2 CoS priority value; In the access VLAN, untagged (no Layer 2 CoS priority value)
Ans C is incorrect – Voice VLAN is only supported on access ports and not on trunk ports, even though the
configuration is allowed.
E & F is incorrect – Port can be trusted or untrusted.
Reference : https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst2960/software/release/12-2_40_se/configuration/guide/scg/swvoip.pdf
mmm, I think it is B D F
why no A? since untagged and none ar valid options that point that voice vlan may be the same as data.
so not a real “own” is required.
-if)#switchport voice [detect cisco-phone] vlan |dot1p|none|untagged
vid: voive vlan vid, data untagged only
dot1p: voice vlan0 tagged prio5 data passtrough dot1q
untagged: voice vlan 4095=>untag data untagged only
none: voice no info
Answer C is correct:
Although you can configure the IP phone uplink as a trunk or nontrunk, the real consideration
pertains to how the voice traffic will be encapsulated. The voice packets must be
carried over a unique voice VLAN (known as the voice VLAN ID or VVID ) or over the
regular data VLAN (known as the native VLAN or the port VLAN ID , PVID ). The QoS
information from the voice packets also must be carried somehow.
Answer C seems incorrect as
‘Voice VLAN configuration is only supported on switch access ports; voice VLAN configuration is not supported on trunk ports”