[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]


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.