How many bytes does the EthernetII header (without VLAN TAG) include?

Question

Options

• A18
• B14
• C22
• D32

• A
  14% (5)
• B
  75% (27)
• C
  6% (2)
• D
  6% (2)

Explanation

Option B (14 bytes) is correct because an Ethernet II header contains three fields: a 6-byte destination MAC address, a 6-byte source MAC address, and a 2-byte EtherType field - totaling exactly 14 bytes.

Option A (18 bytes) is the trap most test-takers fall into: it represents the header size when an 802.1Q VLAN tag is present, which adds 4 bytes to the standard header. The question explicitly excludes the VLAN tag. Option C (22 bytes) has no standard basis in Ethernet II framing and does not correspond to any recognized header variant. Option D (32 bytes) is similarly not a real Ethernet header size and may be confused with unrelated protocol overhead values.

Memory tip: Break the 14 bytes into parts - 6 (Destination MAC) + 6 (Source MAC) + 2 (EtherType) = 14. If you see 18, remember that is "14 plus a 4-byte VLAN tag."

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