Zte ZXR10 T1200, User Manual

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ZXR10 T600/T1200 User Manual (IPv6 Volume)
This mechanism is used by nodes to determine an address pre-
fix that is used to specify the link-local address and an address
prefix that must be sent to a router for forwarding.
� Parameter Discovery
This mechanism helps nodes to determine the information like
link-local MTU.
� Address Auto Configuration
This mechanism is used for IPv6 node auto configuration.
� Address Resolution
This mechanism substitutes ARP and RARP to help nodes de-
termine the link-layer address of the local node, namely the
neighbor, from the destination IP address.
� Next Hop Determination
This mechanism is meant to determine the next destination of
a packet, that is, determine whether the destination of a packet
is on a local link. If it is on the local link, then the next hop is
the destination. Otherwise, the packet needs to be routed and
the next hop will serve as a router. The neighbor discovery can
be used to determine a router to be used.
� Neighbor Unreachable Detection
Neighbor discovery can help nodes to determine whether a
neighbor (destination node or router) is reachable.
� Repeated Address Detection
Neighbor discovery helps a node to determine whether an ad-
dress it wants to use has been occupied on the local link.
� Redirection
Sometimes the forwarding router selected by a node is not
the optimum for a packet to be forwarded. In this case, the
forwarding router can redirect the node to send the packet to
an optimum router.
For example, the node sends the packet that originally is to be
sent to the Internet to the default router that provides service
for the intranet of the node. This intranet router can redirect
the node, thus sending the packet to the Internet router that
is connected with the same local link.
The neighbor discovery is implemented by defining the special
ICMP packets, including:
�
Router Advertisement
This packet requires the router to advertise its availability pe-
riodically, as well as the links and Internet parameters for con-
figuration. These advertisements contain the network address
prefix in using, the suggested hop-by-hop limiting value and
the local MTU indication, and flag of the auto configuration type
to be used by a specified node.
�
Router Solicitation
A host can solicit the local router to send its router advertise-
ment immediately. The router must send these advertisements
periodically. However, if it receives a router request packet, it
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