Ipv 6 Ospf; Introduction To Ospfv3 - 3Com Switch 4800G 24-Port Configuration Manual

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Introduction to
OSPFv3
OSPFv3 Overview
OSPFv3 Packets
IP 6 OSPF
V
n
The term "router" in this document refers to a Layer 3 switch running routing
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protocols.
The Switch 4800G only support single OSPFv3 process.
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OSPFv3 is OSPF (Open Shortest Path First) version 3 for short, supporting IPv6 and
compliant with RFC2740 (OSPF for IPv6).
Identical parts between OSPFv3 and OSPFv2:
32 bits router ID and area ID
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Packets: Hello, DD (Data Description), LSR (Link State Request), LSU (Link State
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Update), LSAck (Link State Acknowledgment)
Mechanisms for finding neighbors and establishing adjacencies
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Mechanisms for LSA flooding and aging
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Differences between OSPFv3 and OSPFv2:
OSPFv3 now runs on a per-link basis, instead of on a per-IP-subnet basis.
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OSPFv3 supports multiple instances per link.
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OSPFv3 identifies neighbors by Router ID, while OSPFv2 by IP address.
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OSPFv3 has also five types of packets: hello, DD, LSR, LSU, and LSAck.
The five packets have the same packet header, which different from the OSPFv2
packet header is only 16 bytes in length, has no authentication field, but is added
with an Instance ID field to support multi-instance per link.
Figure 143 gives the OSPFv3 packet header.
Figure 143 OSPFv3 packet header
0
Version #
3 C
V ONFIGURATION
Type
Router ID
Area ID
Checksum
15
Packet length
Instance ID
31
0