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VLAN Trunking 4

November 24th, 2019 Go to comments

Question 1

Question 2

Question 3

Question 4

Explanation

If an access port receives a packet with an 802.1Q tag in the header other than the access VLAN value, that port drops the packet without learning its MAC source address.

Reference: https://www.cisco.com/c/en/us/td/docs/switches/datacenter/nexus5000/sw/layer2/b_Cisco_Nexus_5000_Series_NX-OS_/Cisco_Nexus_5000_Series_NX-OS__chapter6.html

In fact this question is unclear because if an access port receives an 802.1Q tagged frame with its VLAN value, the access port will accept it (answer D)

Question 5

Question 6

Explanation

802.1Q frames are distinguished from ordinary Ethernet frames by the insertion of a 4-byte VLAN tag into the Ethernet header. The DATA field may vary from 46 to 1500 bytes. Therefore the minimum Ethernet frame size is 68 bytes (6bytes + 6bytes + 4 bytes + 2 bytes + 46 bytes of DATA + 4 bytes) while the maximum size is 1522 bytes.

802.1q_header.png

Comments
  1. Q3 Wrong
    February 8th, 2020

    VID is 1-4094
    A 12-bit field specifying the VLAN to which the frame belongs. The hexadecimal values of 0x000 and 0xFFF are reserved. All other values may be used as VLAN identifiers, allowing up to 4,094 VLANs.

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