5
Link State Acknowledgement Packet
Table 10-3 OSPF Packet Type
3)
Router ID:
ID of the router sending this packet.
4)
Area ID
：
ID of the area that the router interface sending this packet belongs to.
5)
Authentication Type:
The authentication type applied by this packet. The segment
marked with * in the rear is regarded as essential information of authentication, as shown in
the table below.
Type
Code
Authentication
Name
Features
0
Non-Authentication The 64-bit authentication information fields behind
are all 0.
1
Plain-text
Authentication
The 64-bit authentication information behind is the
password to authenticate.
2
MD5 Ciphertext
Authentication
The Key ID, authentication data length and
encryption serial number work together to perform
MD5 Ciphertext Authentication
Table 10-4 Authentication Type
2.
HELLO Packet
OSPF routers send Hello packets to each other to find neighbor routers in the network and to
maintain the mutual adjacency relationship. Only when two routers send Hello packets carrying
the same interface parameters, can they become neighbors.
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