Re: LL70: Use of the term "valid"

> From: "Peter Johansson" <[email protected]>
> At 09:47 AM 5/18/2004 -0700, Bernard Aboba wrote:
>=20
> >"A "valid routable address" is a routable address which is either=20
> >statically assigned or whose lease has not expired and that passes =
the
> >reachability test described in section 2 of "Detection of Network=20
> >Attachment (DNA) in IPv4" [DNAv4]."
>=20
> I would go the extra step and say: "A routable address is an address =
that=20
> is either statically assigned or whose lease has not expired and that=20
> passes the reachability test described in section 2 of "Detection of=20
> Network Attachment (DNA) in IPv4" [DNAv4]."

If this change is made, we are back to square one - the protocol depends =
on the definition of a routable address and that definition depends on =
the reference [DNAv4] which is therefore normative - and is problematic =
because it is an unapproved draft.

I think that the use of "valid" conveys meaning because it helps people =
grasp the idea that a host may have been configured with an address =
which was previously valid but although still configured, is no longer =
useable because the network has changed (e.g. the host moved to a new =
network). This is a common case and there is often good reason not to =
simply unconfigure that address because the host may soon be moved back =
to a context in which it is valid - meanwhile assigning an IPv4LL =
address provides some connectivity.

The validity of a configured address is difficult to establish because =
the context in which it is intended to operate or becomes invalid can =
vary. Therefore I think that all we can do is explain the concept and =
present the DNAv4 reachability test as a useful example (informative) =
rather than a definition (normative) of validity.

I suggested alternative text in an earlier email.

> Please also note the grammatical correction, "which" to "that".

I would dispute that English grammar is so clear cut. In this context =
"that" or "which" both seem acceptable and either conveys the meaning =
well so I can happily accept your ammendment - or not.

Philip