Le 22/02/2017 à 15:17, Lorenzo Colitti a écrit :
[...]
A fixed prefix length is also very beneficial because it allows hosts
to extend the network indefinitely at layer 2 without giving up the
benefits provided by autoconfiguration and end to end connectivity.
I would agree bridging can extend to some extent. But not indefinitely.
I would argue routing extends beyond what bridging can extend.
It means that ill-informed or ill-intentioned network administrators
cannot use addressing to constrain apps in a way that leads to
suboptimal user experience.
Maybe well-intentioned admins consider DHCP too, because it does not
have that /64 limit.
I have seen DHCPv6 running fast on smartphones on cellular links.
That sort of thing obviously does not happen in the 2914 or 15169
backbone. It does happen in lots of other places.
2914, 15169?
Alex
On Wed, Feb 22, 2017 at 1:44 PM, Christopher Morrow
<christopher(_dot_)morrow(_at_)gmail(_dot_)com
<mailto:christopher(_dot_)morrow(_at_)gmail(_dot_)com>>
wrote:
On Tue, Feb 21, 2017 at 10:51 PM, Lorenzo Colitti <lorenzo(_at_)google(_dot_)com
<mailto:lorenzo(_at_)google(_dot_)com>> wrote:
On Wed, Feb 22, 2017 at 12:12 PM, Christopher Morrow
<christopher(_dot_)morrow(_at_)gmail(_dot_)com
<mailto:christopher(_dot_)morrow(_at_)gmail(_dot_)com>>
wrote:
But the configuration cost and management overhead is not
proportional to the hosts that are served by those interconnections,
it is proportional to the number of interconnections. A 10x100G
peering interconnection that serves X million hosts is one interface
that has to be managed.
isn't the dicsussion here really: "If you want to use /64 go ahead,
if you want to use /121 go for it, if you want to use SLAAC you'll
get a /64 and like it"
Not sure. I for one wouldn't agree with that position, because I
don't see that /121 has enough advantages over /127 and /64 - and few
enough downsides for general-purpose hosts - to make it a good idea
in general.
I don't think /121 is anymore special than /127... or /64. My point
was we don't care what prefix people use, generally, that there are
cases where a /64 is required and that's fine, there are cases where
/64 isn't and people can do what they want there. It's simple enough
to do SLAAC/64 on lans and other places.
Requiring /64 or /127 and nothing else means when you do have to do a
/120 or something else you MAY end up fighting vendor problems
because they made assumptions about: "only ever 64 or 127".