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Figure 73   Area and route summary

The Switch 8800 Family series support the following OSPF features:

■

Support stub areas: OSPF defines stub areas to decrease the overhead when 
the routers within the area receive ASE routes.

■

Support NSSA: OSPF defines NSSA areas, surmounting the restriction of stub 
areas on topology. NSSA is the abbreviation of Not-So-Stubby Area.

■

Support OSPF Multi-Process: A router runs multiple OSPF processes.

■

Share the discovered routing information with other dynamic routing 
protocols: OSPF currently can import static routes and routes of other dynamic 
routing protocols such as RIP into the autonomous system of the router, or 
advertise the routing information discovered by OSPF to other routing 
protocols.

■

Authenticator: OSPF provides clear text authenticator and MD5 encryption 
authenticator to authenticate packets transmitted between neighboring 
routers in the same area.

■

Flexible configuration for the router port parameter: On the router port, you 
can configure the following OSPF parameters: output cost, Hello packet 
interval, retransmission interval, port transmission delay, route precedence, 
invalid time for adjacent routers, packet authentication mode, packet 
authenticator, and others.

■

Virtual connection: Creates and configures virtual connections.

■

Abundant debugging information: OSPF provides abundant debugging 
information, consequently helping users to diagnose failure

Open Shortest Path First (OSPF) is an internal gateway protocol. It is developed by 
IETF based on link state algorithm. OSPF version 2 (RFC2328) is now commonly 
used.

Graceful Restart (GR) is designed to keep the OSPF routing data normal when 
abnormal switchover occurs on the switch, so that critical services will not be 
interrupted.

Area 12

Area 8

Area 19

Area 0

Virtual Link

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RTA