Owen DeLong wrote:
LLA and ULA and whatever random prefix you may wish to use for loopback,
whether in IPv6 or even IPv4 have none of these qualities.
And if we implement the proposal at hand, which as near as I can tell you are
supporting, that changes.
Having trouble following your desired outcome here. It seems as if you both
want 127.0.0.0/8 to retain it’s unique properties
as deterministically loopback only and also want the benefits of repurposing it
as GUA.
Have cake, Eat cake, please to pick only one.
Let me clear that up then.
I support serious consideration of the idea. My desired outcome is to
see ideas like these either adopted or not but based solely on their own
merits and especially in their own protocol context. And that folk who
have studied the issue and invested their efforts be taken seriously and
not be met with undeserved and might I add, unkind, scorn.
(I havent studied the issue or invested the effort, so you may continue
to direct your scorn this way)
Its well past time to stop behaving as if we are a bunch of teenagers on
a private BBS.
I like the loopback prefix feature of IPv4.
I can easily concede that its too large, especially in this day and age.
And that there is a good chance that significant benefit can come from
addressing that before IPv4 becomes obsolete.
I question the lack of dedicated loopback feature in IPv6 and I
acknowledge that yes, you can accomplish the same with non loopback
prefixes by essentially assigning them to loopback, but point out that
that does not make them the same thing.
I can understand that sometimes you may explicitly not want to use the
loopback prefix for loopback applications. In fact many times. However,
you dont really have much options when it comes to IPv6.
And I discuss IPv6 loopback simply because of the pushback directed in a
non-meritorious fashion from folk who apparently believe simultaneously
that IPv6 is superior in every way to IPv4 and that any
improvements|changes to IPv4 somehow endanger IPv6 imminent dominance.
having a prefix
dedicated to that purpose globally vs. allowing each site that cares to choose
their own doesn’t seem like the best
tradeoff.
Owen
But this is how it is to be done in IPv6, so lets get some lack-of-feature
parity going with IPv4.
I’m all for IPv6 having better implementations than IPv4 rather than mere
feature parity.
Actually I am (somewhat facetiously) suggesting that IPv4 have
non-feature parity with IPv6 by taking away its loopback prefix.
IMHO, having additional loopbacks be assigned from either LLA or ULA space (or
even GUA, really)
where that is needed is a superior choice vs. 127.0.0.0/8.
Anyone who wants to assign routable IPv4 to loopback is free to do so
and there are plenty of IPv4 ranges to choose from.
The converse is not true in IPv6.
For one thing, the alternative addressing schemes (other than LLA) allow for
routing of the
addresses off the box even though they are configured on loopback interfaces.
There are
a number of situations where this can be a useful way to ensure that the
addresses remain
usable regardless of the up/down state of connectivity on any particular
non-loopback
interface on the box.
It’s one of the reasons, for example, that virtually every IBGP speaking router
has a GUA
or ULA/1918 loopback address which is routed in the IGP and almost all IBGP
sessions
are terminated on those loopback interfaces.
Owen
And its the fairly common way of implementing anycast services. But that
is not what we are addressing on this thread.
I actually think that IPv6 evangelicals should welcome any all ideas
like this, especially if they believe it will further degrade the
overall state of IPv4, because that should only serve as stronger
impetus for IPv6 deployment. That mode of thought has been commonly
expressed here and other places before.
Best,
Joe
