> oh is it. i thought virtual links is a good idea. Virtual links is just a hack to overcome some most obvious consequences of limiting area hierarchy to be 1 level deep (backbone as root and everything else is leaf). In the long term hacks rarely make any good. I agree with Acee, on new design it would have been better to place complexity somewhere else. For example, in allowing true area hierarchy.
Anton On 11/16/2010 03:42 AM, p6 c6d6 wrote: > > On Mon, Nov 15, 2010 at 3:20 PM, Acee Lindem <[email protected] > <mailto:[email protected]>> wrote: > > > This is due to the fact that paths via transit area ABRs other than > the virtual link endpoints can be installed. If I were designing a > link-state protocol from scratch, I would not include the complexity > of virtual links as they are specified in OSPF. > > Hope this helps, > Acee > > On Nov 14, 2010, at 9:47 PM, p6 c6d6 wrote: > > > hi, > > > > why should one recalculate routes using transit areas summary > lsas, even if > > better paths exist through transit area. as a virtual link is > considered as > > an unumbered p2p link, it is as good as the router has an > interface to the backbone. > > referring to rfc2328 figure 17, RT1 chooses route network N1 > through RT4, since that > > is an intra-area path, that is in accordance to the path > preference rules of ospf. > > why do we give special treatment for transit areas. If the link > were not a virtual-link and > > if it indeed is real p2p interface in to the backbone, we will not > try to route the data to N1 > > through RT5, since the route through RT4 would be preferred. why > special treatment for > > transit areas, and why can't we extend this treatment to other > areas as well (neglecting > > the fact that area routing is protected by bad routing of other > areas). > > > > thanks in advance > > > > > > <ATT00001..txt> > > > oh is it. i thought virtual links is a good idea. > and for the newly calculated route why do we > have to use the associated area as backbone area > though the path is still through transit area ? > > > > > _______________________________________________ > OSPF mailing list > [email protected] > https://www.ietf.org/mailman/listinfo/ospf _______________________________________________ OSPF mailing list [email protected] https://www.ietf.org/mailman/listinfo/ospf
