Neighbor Discovery Proxies are used to provide an address presence on
a link for nodes that are no longer present on the link. They allow
a node to receive packets directed at its address by allowing another
device to perform Neighbor Discovery operations on its behalf.
Neighbor Discovery Proxy is used in Mobile IPv6 and related protocols
to provide reachability from nodes on the home network when a Mobile
Node is not at home, by allowing the Home Agent to act as proxy. It
is also used as a mechanism to allow a global prefix to span multiple
links, where proxies act as relays for Neighbor Discovery messages.
Neighbor Discovery Proxy currently cannot be secured using Secure
Neighbor Discovery (SEND). Today, SEND assumes that a node
advertising an address is the address owner and in possession of
appropriate public and private keys for that node. This document
describes how existing practice for proxy Neighbor Discovery relates
to SEND. This document is not an Internet Standards Track
specification; it is published for informational purposes.