Transit LAN vs. Individual LANs

Mark Smith random at
Sat Feb 25 22:26:26 UTC 2006

On Sun, 26 Feb 2006 08:41:45 +1030
Mark Smith <random at> wrote:

To qualify this better, there are no DR/BDR on the segment at all,
rather than there being ones that just aren't used :

> Automatic nighbour discovery via multicast hellos still happens, the
> difference is that the routers establish direct adjacencies between each
> other, rather than with the DR. While this costs additional RAM, and CPU
> during the SPF calc, the benefit of avoiding DR/BDR elections, and the
> 'DR/BDR' approximately 40 second listening phase when a third and
> subsequent routers come online may be well worth those costs.


        "Sheep are slow and tasty, and therefore must remain constantly
                                   - Bruce Schneier, "Beyond Fear"

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