Link state database in OSPF

[thangaRasu]

I would like to know the difference between link state database and routing table in OSPF and when will be the digraph formed?

[patrick.preuss]

Hi

A Router has only one routing table. This holds all aktiv routes, regardless from which protocol they are learnd.

The linkstate db stores The lsa ( link State advertisements) generatet by The routers and calulates from this via shortest path fisrt , the spf in ospf. A tree or a table of possible routes to insert them into The routing table.

Hth

Patrick

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[Abzal]

Hi,

OSPF Link-state Database it is current map of the network. It is built by LSAs that routers in OSPF domain exchanges during convergence time. It stores all network segments. Router in OSPF domain exchanges LSAs that contain active links and network segments reachable via router. On broadcast domain such as Ethernet all routers exchange those LSAs with elected Designated Router(DR). Once DR builds full database it floods this information to other routers in OSPF domain.

When routers finish mapping network topology they calculate best-path to each network segment by SPF alghoritm. And insert them to Routing Table. Each link has a cost of the link that you can change and influence a routing table.

Hope it will help.

Best regards,
Abzal