It's like that because RFC says so :-). Each LSA has a header that must be respected. One of the fields in this header is the LSA ID and another is advertising router's RID. In the case of Router LSA, they will be the same.
OSPF recognizes 3 types of links in Router LSA: 1. Stub 2. Point-to-point 3. Transit Stub: links not connected to other routers. Point-to-point: links connected to other routers on p2p and p2m links. Transit: broadcast and non-broadcast links. -- Marko Milivojevic - CCIE #18427 (SP R&S) Senior CCIE Instructor - IPexpert On Thu, Oct 18, 2012 at 10:14 AM, vishal bhugra <[email protected]> wrote: > Hello Marko > > Sorry If I misunderstood. > > As per my understanding Router LSA is about telling its ALL interface(link) > status. Then why it choses LINK state ID to be same as Router ID. > > If both means same, then why we have two fields. > > Secondly which interfaces (links) ar considered to be Stub and which are > considered to be transit. > > On Thu, Oct 18, 2012 at 8:21 PM, Marko Milivojevic <[email protected]> > wrote: >> >> Router LSA's ID (router-id) will always be the same as the advertising >> router, because only the advertising router can advertise Router >> LSAs... if that makes sense :-) >> >> -- >> Marko Milivojevic - CCIE #18427 (SP R&S) >> Senior CCIE Instructor - IPexpert >> >> On Thu, Oct 18, 2012 at 9:44 AM, vishal bhugra <[email protected]> >> wrote: >> > Hello Marko >> > >> > Thanks for your valuable comments, I have already read this document. >> > But >> > this document do not answer my questions. >> > >> > On Thu, Oct 18, 2012 at 7:40 PM, Marko Milivojevic <[email protected]> >> > wrote: >> >> >> >> This might help. >> >> >> >> >> >> >> >> http://blog.ipexpert.com/2010/08/11/quick-look-into-ospf-database-router-lsa/ >> >> >> >> -- >> >> Marko Milivojevic - CCIE #18427 (SP R&S) >> >> Senior CCIE Instructor - IPexpert >> >> >> >> On Thu, Oct 18, 2012 at 7:53 AM, vishal bhugra >> >> <[email protected]> >> >> wrote: >> >> > Hello experts >> >> > >> >> > I was reading out the Router LSA and have few doubts, need your >> >> > expert >> >> > comments :- >> >> > >> >> > LS Type: Router Links >> >> > Link State ID: 192.168.30.10 ---------- Why and how >> >> > link >> >> > state ID is always same as the router ID >> >> > Advertising Router: 192.168.30.10 >> >> > >> >> > Which all networks are considered as stub and transit in Router LSA >> >> > >> >> > >> >> > Thanks & regards >> >> > >> >> > Vishal >> >> > +91 8587900305 >> >> > >> >> > Best way to predict the future ..... is to create it >> >> > _______________________________________________ >> >> > For more information regarding industry leading CCIE Lab training, >> >> > please visit www.ipexpert.com >> >> > >> >> > Are you a CCNP or CCIE and looking for a job? Check out >> >> > www.PlatinumPlacement.com >> >> > >> >> > http://onlinestudylist.com/mailman/listinfo/ccie_rs >> > >> > >> > >> > >> > -- >> > Thanks®ards >> > >> > >> > Vishal >> > +91 8587900305 >> > >> > Best way to predict the future ..... is to create it >> > > > > > > -- > Thanks®ards > > Vishal > +91 8587900305 > > Best way to predict the future ..... is to create it > _______________________________________________ For more information regarding industry leading CCIE Lab training, please visit www.ipexpert.com Are you a CCNP or CCIE and looking for a job? Check out www.PlatinumPlacement.com http://onlinestudylist.com/mailman/listinfo/ccie_rs
