The ospfv2 protocol is also the first important routing protocol that all students learned when they first came into contact with the network, and now we have entered the ipv6 era, so the protocol that replaces ospfv2 in the ipv6 era is today’s protagonist—ospfv3.
The ospfv 3 protocol is an independent routing protocol based on the basic principles of ospfv2 and enhanced. The agreement number is still 89. Everyone must be clear that the ospfv3 protocol does not directly extend the ospfv2 protocol, but a newly developed routing protocol independent of any specific network layer. In order to achieve this goal, the internal router information of ospfv3 has been redesigned.
According to the above, there must be certain differences between ospfv 3 and ospfv2, and these differences are mainly:
1 ) Link-based operation
2 ) Use link local address
3 ) The link supports multiple instance multiplexing
4 ) Uniquely identify neighbors by router id
5 ) Changes in certification
6 ) Support for stub area
7 ) Different messages
8 ) The difference in option fields
9 ) The type and content of LSA are different
What we mainly explain today is that the link supports multiple instance multiplexing; in the ospfv 2 protocol, the physical interface of the ospfv2 device can only be bound to one instance instance; and the ospfv3 protocol allows the physical interface of the ospfv3 device to be multiple Two instance instances are bound and do not interfere with each other; that is to say, the same physical port can establish different ospfv3 neighbor relationships in different instances and send ospfv3 messages without affecting each other. This benefit can fully share the same chain Road resources.
According to the figure above, the four devices of RTA, RTB, RTC and RTD are interconnected on the same link. Because these devices have enabled the ospfv 3 protocol, the E1/1 port of RTA, the E1/1 port of RTB and The E1/2 port of RTC can be bound to the instance of instance1; while the E1/1/port of RTA, the E1/1 port of RTB, and the E1/3 port of RTD can be bound to the instance of instance2; at this time, RTA, RTB and RTC establish the adjacency relationship of ospfv3 in the instance1 instance, while RTA, RTB and RTD establish the adjacency relationship of ospfv3 in the instance2 instance. At this time, in different instances, these devices can share the same link to exchange ospfv3 information without affecting each other.
The experimental verification is as follows:
Purpose:
1 ) R1 and R3 establish an ospfv3 adjacency relationship in instance1
2 ) R2 and R3 establish ospfv3 adjacency in instance2
The first step: configure ipv 6 address (omitted)
Step 2: Configure ospfv 3
R1 ：
Ospfv 3
Router-id 1.1.1.1
Interface g0/0/0
Ospfv3 1 area 0 instance 1
Interface loopback 0
Ospfv3 1 area 0 instance 1
R2:
Ospfv3 1
Router-id 2.2.2.2
Interface g0/0/0
Ospfv3 1 area 0 instance 2
Interface loopback 0
Ospfv3 1 area 0 instance 2
R3:
Opsfv3 1
Router-id 3.3.3.3
Interface g0/0/0
Ospfv3 1 area 0 instance 1
Interface loopback 0
Ospfv3 1 area 0 instance 1
Ospfv3 10
Router-id 33.33.33.33
Interface g0/0/0
Ospfv3 10 area 0 instance2
Interface loopback 0
Ospfv3 10 area 0 instance 2
Step 3: Verification
At this time, R3 establishes the adjacency relationship of ospfv 3 with R1 and R2 in different instances . The messages exchanged between them do not affect each other and share the same link.