On 2/15/2011 5:08 AM, Iljitsch van Beijnum wrote:
On 14 feb 2011, at 6:46, Frank Bulk wrote:
Requiring them to be on certain well known addresses is restrictive and
creates an unnecessary digression from IPv4 practice. It's comments like
this that raise the hair on admins' necks. At least mine.
I don't get this. Why spend cycles discovering a value that doesn't need to
change?
Because it will change. At some point, this paradigm will shift. The
service hierarchy will change, the protocol methodology will change, the
network topology will change... *something* will happen that will make a
well-known address, hard-coded in a million places, change from a boon
to a massive headache.
One of the biggest problem v6 seems to have had is that its designers
seemed to think the problem with v4 was that it didn't have enough
features. They then took features from protocols that ipv4 had killed
over the years, and added them to v6, and said, "Look, I made your new
IP better." And then, when the operators groaned and complained and
shook their heads, the ipv6 folks called them "backward" and "stuck in
ipv4-think." But the fact of the matter is, operators want a protocol
to be as simple, efficient, flexible, and stupid as possible. They
don't want the protocol tied to how things work today; it needs to be
open to innovation and variety. And part of that is that an address
needs to be just an address, with no other significance other than being
unique and routable. The moment an address has any significance beyond
the network layer, it's a liability waiting to happen.
