[dhcwg] VIV*O options.

Does anyone know of a client or server that has implemented VIV*O (RFC3925)?
I'm looking for targets for interoperability testing.

RFC4243 relay agents would be interesting too.

While looking at this, I had to come to grips with a minor code reuse
problem I'd like to solicit opinions on.

We currently use the same code to dissect the options buffer as we do
any encapsulated space (so, VIV*O would use this as well).

This loop that traverses options looks for PAD and END options, which
RFC 3925 explicitly states are not special cases, with no special
handling.  Unless I'm mistaken, RFC 4243 makes no mention.

That means I get to add more instructions to this loop, or write a new
loop, neither of which I particularly fancy.

However, enterprise id 0 is reserved according to IANA, which I take to
mean is an illegal value, so it shouldn't appear in packets at all.

My most-code-reused solution, then, is to use 0x00000000 as both PAD
and END options for this encapsulated space (END trumps PAD, so this
causes the server to stop processing the buffer if it's encountered -
a zero is effectively an error condition).

That would be true for any encapsulated space with no defined END option.

What are folks opinions on this approach, not just for VIV*O, but for
encapsulated spaces in general?

-- 
David W. Hankins		"If you don't do it right the first time,
Software Engineer			you'll just have to do it again."
Internet Systems Consortium, Inc.		-- Jack T. Hankins