TCP/IPv6 Configuration and Management Manual (G06.24+)

IPv6 Fundamentals
HP NonStop TCP/IPv6 Configuration and Management Manual—524523-008
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Neighbor Discovery Protocol
How hosts discover the set of address prefixes that define which destinations are
on-link for an attached link. (Nodes use prefixes to distinguish destinations that
reside on-link from those only reachable through a router.)
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Parameter discovery
How a node learns such link parameters as the link MTU or such Internet
parameters as the hop-limit value to place in outgoing packets.
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Address autoconfiguration
How nodes automatically configure an address for an interface.
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Address resolution
How nodes determine the link-layer address of an on-link destination (a neighbor)
given only the destination's IP address.
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Next-hop determination
How mapping an IP destination address into the IP address of the neighbor to
which traffic for the destination should be sent occurs. The next- hop can be a
router or the destination itself.
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Neighbor unreachability detection
How nodes determine that a neighbor is no longer reachable. For neighbors used
as routers, alternate default routers can be tried. For both routers and hosts,
address resolution can be performed again.
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Duplicate address detection
How a node determines that an address it wishes to use is not already in use by
another node.
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Redirect
How a router informs a host of a better first-hop node to reach a particular
destination.
Neighbor discovery defines five ICMP packet types: a pair of router solicitation and
router advertisement messages, a pair of neighbor solicitation and neighbor
advertisements messages, and a redirect message. The messages serve these
purpose:
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Router solicitation
When an interface becomes enabled, hosts can send out router solicitations that
request routers to generate router advertisements immediately rather than at the
routers’ next scheduled time.
•
Router advertisement
Routers advertise their presence together with various link and Internet parameters
either periodically, or in response to a router solicitation message. Router