nerdexam
Cisco

200-301 · Question #1500

Refer to the exhibit. The IPv6 address for the LAN segment on router R1 must be configured using the EUI-64 format. When configured which ipv6 address is produced by the router?

The correct answer is B. 2001:db8:1a44:41a4:C801:BEFF:FE4A:1. The EUI-64 process generates an IPv6 interface identifier by taking a 48-bit MAC address, inserting 'FFFE' in the middle, and inverting the 7th bit of the first byte.

Submitted by viktor_hu· Mar 5, 2026IP Connectivity

Question

Refer to the exhibit. The IPv6 address for the LAN segment on router R1 must be configured using the EUI-64 format. When configured which ipv6 address is produced by the router?

Exhibits

200-301 question #1500 exhibit 1
200-301 question #1500 exhibit 2

Options

  • A2001:db8:1a44:41a4:C081:BFFF:FE4A:1
  • B2001:db8:1a44:41a4:C801:BEFF:FE4A:1
  • C2001:db8:1a44:41a4:4660:592F:FE65:1
  • D2001:db8:1a44:41a4:C800:BAFE:FF00:1

How the community answered

(45 responses)
  • A
    13% (6)
  • B
    78% (35)
  • C
    7% (3)
  • D
    2% (1)

Why each option

The EUI-64 process generates an IPv6 interface identifier by taking a 48-bit MAC address, inserting 'FFFE' in the middle, and inverting the 7th bit of the first byte.

A2001:db8:1a44:41a4:C081:BFFF:FE4A:1

This option does not correctly apply the EUI-64 conversion rules regarding the 7th bit inversion or the structure of FFFE insertion based on a typical MAC address.

B2001:db8:1a44:41a4:C801:BEFF:FE4A:1Correct

For EUI-64, if the original MAC address is 88:01:BE:4A:00:01 (assuming this from the exhibit), it's split, FFFE is inserted in the middle, resulting in 8801:BEFF:FE4A:0001. The 7th bit of the first byte '88' (binary 10001000, 7th bit is 0) is then inverted to 'C8' (binary 11001000), producing C801:BEFF:FE4A:0001 as the interface ID, which appended to the given prefix 2001:db8:1a44:41a4: forms the complete IPv6 address.

C2001:db8:1a44:41a4:4660:592F:FE65:1

This option's interface identifier (4660:592F:FE65:1) deviates significantly from the EUI-64 rules, failing to incorporate 'FFFE' correctly or reflect the original MAC address segments.

D2001:db8:1a44:41a4:C800:BAFE:FF00:1

This option's interface identifier (C800:BAFE:FF00:1) incorrectly inserts 'BAFE' and 'FF00' instead of the standard 'FFFE' in the middle of the MAC address to form the EUI-64 identifier.

Concept tested: IPv6 EUI-64 address generation

Source: https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/ipaddr_ipv6/configuration/15-s/ipv6-15-s-book/ip6-eui64.html

Topics

#IPv6 addressing#EUI-64#SLAAC

Community Discussion

No community discussion yet for this question.

Full 200-301 Practice