In article <Pine.GSO.4.61.0412011235160.13890@rfhpc8317>,
Hubert Feyrer <hubert@feyrer.de> wrote:
>
>On Wed, 1 Dec 2004, Peter Postma wrote:
>> and this removes that limit. How people are going to use the multiple
>> devices is beyond the scope of this thread.
>
>No, I think it is exactly the question being asked - why would we want 
>this?

Because it is pointless to have needs-count devices. There are very
few left (most of them are isdn and ppp/sl related). We can have
all devices able to have an arbitrary number of instances. For the
most part you either have allocated too many that you'll never use
wasting kva, or you've allocated too little and you need to recompile
a new kernel. The code diffs to do this in most changes save kva!
Also, in a dynamically loaded driver environment you'd like to
limit static allocations to a minimum.

For this particular case I can envision cisco-like "LoopbackN"
functionality where you create loopback devices to agregate multiple
physical interfaces, or as a virtual interface with the highest IP
address of the router, used in protocols that choose the highest
numbered interface such as OSPF.

christos