Re: IPv6 /64 links (was Re: ipv6 book recommendations?)

[Masataka Ohta <mohta () necom830 hpcl titech ac jp>]

Tony Hain wrote:

> > It is because you avoid to face the reality of MLD.

> MLD != ND
> MLD == IGMP

OK.

> ND ~= ARP

Wrong, because ND requires MLD while ARP does not.

> ND is less overhead on end systems than ARP

Today, overhead in time is more serious than that in processor
load.

As ND requires MLD and DAD, overhead in time when addresses are
assigned is very large (several seconds or more if multicast is
not very reliable), which is harmful especially for quicking
moving mobile hosts.

> because it is only received by
> nodes that are subscribed to a specific multicast group rather than
> broadcast reception by all.

Broadcast reception by all is good because that's how ARP can
detect duplicated addresses without DAD overhead in time.

> Multicast group management is inherently noisy,

Thus, IPv6 is inherently noisy while IPv4 is not.

> but a few more bits on the
> wire reduces the load on the significantly larger number of end systems. Get
> over it ...

First of all, with CATENET model, there is no significantly large
number of end systems in a link.

Secondly, even if there are significantly large number of end
systems in a link, with the end to end principle, network
equipments must be dumb while end systems must be intelligent,
which means MLD snooping is unnecessary and end systems must
take care of themselves, violation of which results in
inefficiencies and incompleteness of ND.

                                                Masataka Ohta