Zte ZXR10 8900 Product Description page 67

4.3.9.2 OSPF Protocol
As an internal gateway protocol (IGP) developed by IFTF, the OSPF is based on the link
status and the Shortest Path First (SPF) algorithm. The OSPF can converge the routing
table in a very short period, and avoid loops, a capability extremely important for mesh
networks or LANs connected with multiple bridges. In every device that runs OSPF, a
unified database is maintained to describe the topology of the autonomous system. This
database is composed of the local status information of each device, for example,
available interface and neighbor of the device, status of the network connected with the
device, and external route connected with the autonomous system. The OSPF uses the
link status algorithm to calculate the shortest paths from each area to all the destinations.
When one device first starts to work or any route changes, this device helps the device
that runs OSPF to disperse the LSAs to all the devices in the area of the same level.
These LSAs contain the link status of this equipment and its association information with
its neighbors. The information collected from these LSA forms the link status database.
In this area, each of all the devices has a particular database to describe the topology of
the area.
The OSPF protocol of the ZXR10 8900 perform the following functions:
•
Making a hierarchical network topology that is suitable for large interconnection
networks
•
Using the Dijiksra algorithm in route calculation so that the system can follow the
network topology change automatically and rapidly
•
Supporting the display and configuration commands from the primary console,
supports the commands, display and MIB variables related to SNMP
•
Supporting authentication of routing protocol packets including simple password
authentication and MD5 authentication to prevent the routing protocol packets from
being tampered
•
Using retransmission and confirmation mechanism to guarantee the reliability in link
status synchronization
•
Supporting multiple different distance measurement plans, for example, physical
distance, delay, throughput, etc.
•
Supporting STUB AREA, NSSA
•
Supporting domain edge and AS edge routers
•
Supporting classless routes and route aggregation
•
Controlling
mapping
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route re-allocation and route filtering through Route Map route
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