On Die, 2008-06-17 at 09:35 +0200, Henning Rogge wrote:
> Am Montag 16 Juni 2008 23:29:46 schrieb Daniel Nitzpon:
[...]
> > i don't grasp the scenarios for fisheye routing loop production:
> >
> > Henning Rogge schrieb:
> >  > The problem can happen at the edge of a fisheye zone. You get an
> >  > "update border" at this point because some packages are not flooded to
> >  > the edge of the network.
> >
> > why is that? can you give an example topology?
> 
> let's just look at a very extreme example.
> 
> we have a linear string of nodes (a total of 6 nodes) and a long connection 
> from node 1 to 6 through other parts of the network.
> 
> 1 -- 2 -- 3 -- 4 -- 5 -- 6
> |                        |
> +.....(many nodes).......+
> 
> Node 1 and 2 loose connection, so node 2 sends a new TC with the changed 
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> topology information. Unfortunately fisheye sends this TC with a TTL of 3, so 
> only nodes 2, 3 and 4 get it.
> 
> Node 1 sends a package to 6, because it does not know about the lost 
                                                                  ^^^^
> connection between 5 and 6, it sends the package to node 2. Node two knows 
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^

Is that difference intentional?

> about the lost connection and about the other way between 1 and 6, so it 
> sends the package back to 1.
> 
> => Routing loop

	Bernd
-- 
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