Usage Scenario
Nonce option contains a random number selected by the sender of a solicitation message. This option prevents replay attacks during packet exchange. For example, a sender sends an NS message carrying the Nonce option and receives an NA message as a response that also carries the Nonce option; the sender verifies the NA message based on the Nonce option.
You can run the display ipv6 nd security nonce command to view the Nonce value in an SEND message and the IPv6 address of the peer interface.