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Q49Network Access

A Cisco engineer must configure a single switch interface to meet these requirements: - Accept untagged frames and place them in VLAN 20 - Accept tagged frames in VLAN 30 when CDP detects a Cisco IP phone Which command set should the engineer apply?

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Community votes
B
89% (8)
C
11% (1)
A
0% (0)
D
0% (0)
Discussion · 19
B 17
Selected Answer: B B has to be the answer. With D, the interface is running in trunk mode. So the access configuration is not considered and vlan 20 will be tagged.
5
My answer was C, this was chatGTP answer when I asked why it can't be C The command set in option C is not right because it includes "switchport mode dynamic auto," which would make the interface become a trunk port if the neighboring device is set to trunk mode. In this scenario, the requirement is to accept untagged frames in VLAN 20 and tagged frames in VLAN 30 when a Cisco IP phone is detected. Therefore, the interface should be configured as an access port in VLAN 20 and a voice VLAN should be configured for VLAN 30. The command set that meets these requirements is option B: switchport mode access switchport access vlan 20 switchport voice vlan 30 Option A is incorrect because it sets the interface to dynamic desirable mode, which could cause the interface to become a trunk port if the neighboring device is set to trunk or dynamic auto mode. It also allows VLAN 30 on the access port, which is not needed. Option D is incorrect because it sets the interface to trunk mode, which is not needed for this scenario.
3
switchport mode access switchport access vlan 20 switchport voice vlan 30 Explanation: switchport mode access is used to set the switchport to access mode, which lets untagged frames enter the VLAN specified by switchport access vlan 20. switchport access vlan 20 assigns untagged frames to VLAN 20. switchport voice vlan 30 configures the voice VLAN for Cisco IP phones. This command makes sure that tagged frames detected by CDP from a Cisco IP phone will be placed in VLAN 30. Option B meets both of the specified requirements.
2
but there is no allow native vlan command from C..so its wrong
2
wow a lot of these answers suck. cmon exam topics
B 2
Selected Answer: B They want UNTAGGED VLAN -> access port
B 2
Selected Answer: B A trunk port can not assign an access vlan
2
Only trunk ports support tagged and untagged frames at the same time. Therefore, option C is the only correct answer.
C 1
Selected Answer: C untagged. so native vlan 20. native vlans let frames pass untagged
1
answer B
1
BBBBBBBB
1
I thought it was C as well, but I guess the "allowed" is missing in the command?
1
Voice vlan works at access... No trunking for that port.
1
please the answer is B, its a true example of a ip phone.
1
B IS correct the phone's port is also a trunk port, this is not a great question also
B 1
Selected Answer: B B is correct, when you have voice and data, it has to be an access port
B 1
Selected Answer: B I think it is B
B 1
Selected Answer: B Per Cisco documentation under the subtopic line Voice VLAN Configuration Guidelines, "Voice VLAN is only supported on access ports and not on trunk ports, even though the configuration is allowed. Quoted directly from the following source: https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst3560/software/release/12-2_44_se/configuration/guide/scg/swvoip.html#wp1033848
B 1
Selected Answer: B This configuration uses an access port, which is a common and valid setup for connecting a Cisco IP phone with a PC behind it: Untagged frames (e.g., from the PC) are put in VLAN 20 (access VLAN). Tagged frames from the IP phone, detected via CDP, are put in VLAN 30 (voice VLAN). Cisco switches support this dual-VLAN capability on access ports when a voice VLAN is configured, making it the simplest and most reliable solution for the requirements.