address for an interface. The link-local address manually set must be a valid link-local address
(FE80::/10).
Automatically generated link-local addresses are recommended because link-local addresses are
used only for communications between link-local nodes usually to satisfy the communication
request of protocols and irrelevant to communications between users.
A global unicast address is equal to an IP address on the IPv4 public network, which is used to
forward data on the public network and mandatory for communications between users.
An EUI-64 address is equivalent to a global unicast address in view of functions. For an EUI-64
address, however, only the network bits need to be specified. Its host bits are transformed from
the MAC address of the interface. For a global unicast address, complete 128 bits of the address
have to be specified.
IPv6 Neighbor Discovery
IPv6 neighbor discovery (ND) is a packet transmission process to identify relationships between
neighboring nodes. The ND protocol replaces the Address Resolution Protocol (ARP), ICMP
Redirect message, and ICMP Router Discovery message on an IPv4 network and provides other
functions.
IPv6 FIB
Connecting network topologies of different types needs the configuration of different routing
protocols. This brings about Routing Information Base (RIB). The RIB is a base of the FIB.
Guided by route management policies, the S2700 obtains minimum necessary forwarding
information from the RIB and adds the information to the FIB. Through the route management
module, you can also add static routes into the FIB.
Forwarding Information Base (FIB) contains minimum necessary information needed by an
S2700 to forward packets. An FIB entry usually contains the destination address, prefix length,
transport port, next-hop address, route flag, time stamp. An S2700 forwards packets according
to FIB entries.
The FIB mechanism consists of two parts: FIB agent (used on the control plane) and FIB
container (used on the forwarding plane). The control plane (FibAgent) is responsible for
interacting with the RM module and downloading the FIB to the forwarding engine. For a
distributed system, the FIB needs to be downloaded to the I/O board.
A FIB contains the following information:
l
Destination address: indicates the network or host a packet is destined for.
l
Prefix length: indicates the length of the destination address prefix. From the prefix length,
you can infer that the destination address is a network address or a host address.
l
Nexthop: indicates the address of the next hop through which the packet reaches the
destination.
l
Flag(s): identifies route characteristics.
l
Interface: indicates the outgoing interface of the packet.
l
Timestamp: time when an FIB entry is generated.
Quidway S2700 Series Ethernet Switches
Configuration Guide - IP Service
5 Basic Configurations of IPv6
Issue 01 (2011-07-15)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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