27.1.2 OSPFv3 function
Although OSPFv3 and OSPF are similar protocols, they operate independently of each other.
- <Structure of this section>
(1) Functional difference with OSPF
The following table describes the functional differences between OSPFv3 (IPv6) and OSPF (IPv4).
|
Functionality |
OSPFv3(IPv6) |
OSPF(IPv4) |
|---|---|---|
|
Forwarding addresses for external AS routes |
NG |
OK |
|
NSSA |
NG |
OK |
|
Per |
NG |
OK |
|
Non-broadcast (NBMA) networks |
NG |
OK |
|
Equal-cost multipath |
OK # |
OK |
|
Virtual links |
OK |
OK |
|
Multi-backbone |
OK |
OK |
|
Graceful restart |
OK |
OK |
|
Stub router |
OK |
OK |
Legend: OK: Supported, NG: Not supported
- #
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The route selection method differs between OSPF (IPv4) and OSPFv3 (IPv6). In equal-cost mode, the smallest next-hop address is selected in OSPF (IPv4), while the next-hop address with the smallest router ID is selected in OSPFv3 (IPv6). If multiple next-hop addresses have the same router ID, the next-hop address for which the smallest interface ID has been advertised in a hello packet is selected.
(2) Domain
The Switch allows the division of an AS into up to four OSPFv3 networks, and can exchange, calculate, and generate routing information for OSPFv3 networks individually. This functionality is called OSPFv3 multi-backbone. Each independent OSPFv3 network is called an OSPFv3 domain.
OSPFv3 must be configured for each OSPFv3 domain.
When OSPFv3 is used with VRFs, each VRF can be partitioned into a maximum of four domains.