OSPFv3 packets
OSPFv3 has the following packet types: hello, DD, LSR, LSU, and LSAck. These packets have the same packet header, which is different from the OSPFv2 packet header. The OSPFv3 packet header is only 16 bytes in length, has no authentication field, and is added with an Instance ID field to support VPN per link.
Figure 105: OSPFv3 packet header
Major fields for OSPFv3 packets are as follows:
Version #—Version of OSPF, which is 3 for OSPFv3.
Type—Type of OSPF packet; types 1 to 5 are hello, DD, LSR, LSU, and LSAck.
Packet length—Packet length in bytes, including header.
Instance ID—Instance ID for a link.
0—Reserved. It must be 0.