Subject: Re: Loopback interface terminology issue
From: Michael Richardson <[email-masked]>
To: "ipv6\@ietf.org" <[email-masked]>
Date: Wed, 18 Oct 2017 12:52:08 -0400
List-Id: "IPv6 Maintenance Working Group \(6man\)" <ipv6.ietf.org>

Brian E Carpenter <[email-masked]> wrote:
    brian> Well yes; indeed this topic is touched on in many RFCs but nowhere is
    brian> it defined as part of the basic architecture, which is my main
    brian> point. Using a concept that has no principal definition is generally
    brian> a source of confusion.

    joel> We tended not to define software interfaces for things which are not
    joel> required for interoperability. How you describe an address which is
    joel> not bound to a physical interface is entirely irrelevant outside the
    joel> scope of your own operating system.

    brian> That's not our experience in trying to be precise in saying what we
    brian> mean in draft-ietf-anima-autonomic-control-plane.

to restate Brian's point slightly differently:

The issue is not to tell people how to implement things in their software,
but rather to make it clear that we need a standard hook on which to hang our
addresses.

We'd rather not use the term "loopback interface" at all here if we had
another name defined in an RFC somewhere.

I think that there is some significant text that might need to be written
when defining this hook when in a strong-host model.

But, let me also ask a different question: are there router operating systems
where there is a way to hang an address on something which is not a
virtual/loopback interface?  If so, what do they call it?

If there are differences in software interfaces in some place that we would
be respecting by abstracting this requirement?
After 35+ years of router operating systems, has anyone actually innovated in this way?

--
Michael Richardson <[email-masked]>, Sandelman Software Works
 -= IPv6 IoT consulting =-