in RFC 2328(for ospf) i see that Link-State-Id and Advertising-Router-Id are same for Router-LSAs(type1).

 For router-LSAs, this field is identical to the
        Link State ID field.  Network-LSAs are originated by the
      network's Designated Router.  Summary-LSAs originated by
        area border routers.  AS-external-LSAs are originated by AS
        boundary routers.

But in my understanding both fields will have same value even for Type-2(Network LSAs). is my understanding right?


For network LSA Link-State-Id will have the interface address which is acting as DR in that network, while Advertising Router-Id field will have the Router-Id of the router having the interface acting as Designated-Router for that network. RouterId can be different(some loopback) while the interface Ip address can be something else.


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