Dense?

[David Perkins <[e-mail]>]

On the Dense vs Sparse questions, the replies still
leave me a little confused. So, "here I go again."

Here is a simple senario: Vendor XXX has a chassis
that has eight slots for boards.  There is no CPU
(i.e., agent) in the chassis, which is really just
a cardcage. The types of cards that vendor XXX
manufactures are the following: 1) power supply
(which has no CPU or agent), 2) router,
3) ethernet repeater, 4) terminal server,
5) "host", 6) FDDI concentrator, and 7) bridge.
No card does more than one "function" and the
complete function is totally done on one card.
(In this simple example, the router is not implemented
to take up two slots, for example.)

All slots are identical so that any card can be
inserted in any slot.

Now, consider the following configuration:
  slot   status
  1-3    empty
   4     power supply
   5     empty
   6     router
   7     empty
   8     terminal server

If an agent (in either the terminal server or the
router) implements the chassis MIB, if
the entries in the slot table are numbered
1 to 8 so that they correspond to the physical
slots is this dense or sparse?

I would say this would be "dense". If the entries
in the slot table were numbered 2 (slot 1), 4 (slot 2),
8 (slot 3), 16 (slot 4), 32 (slot 5), 64 (slot 6),
128 (slot 7), and 256 (slot 8), then I would say these
would be "sparse". However, I don't understand what
situations that this numbering would be appropriate?
And again, would it be Ok for the router that implemented
the chassis MIB to use the first numbering, and the
terminal server that also implemented the chassis
MIB to use the second numbering?

Also note that the power supply is a "dumb"
"logical device" that doesn't have an agent
and doesn't have a MIB (yet).  How does it
fit into the chassis MIB model?

Finally, is this simple example a "good" one to
use for further discussion?  What other additional
information needs to be added (maybe information
about backplane(s))?

Thanks,
/dave perkins, synoptics, 408-764-1516