Vernon Schryver wrote:
>
> > From: Joe Touch <[EMAIL PROTECTED]>
>
> > ...
> > > > would pacbell filtering all multicast at all CPE equipemt fall into your
> > > > bucket, where do you draw the line?
> >
> > At IP, as Bob Braden said.
> >
> > SMTP is _over_ IP.
> >
> > Multicast _redefines_ IP (or portions of the address space thereof); it
> > could be argued that a service provider sells 'Internet' without selling
> > multicast IP.
>
> That grossly overstates the difference between multicast IP services and
> classic IP services. For one thing, many multicast applications work
> fine, albeit with rather reduced scope, when sent to the local IP broadcast
> address instead of a multicast address. For another, since CIDR
> "_redefines_ IP (or portions of the address space thereof", are ISP's
> that sell non-classful blocks not in the IP business?
'Internet' is about speaking IP and ICMP.
There are many variants of routing; none are required to be deployed
_throughout_ the Internet. Static routes are sufficient, and 'who speaks
what routing protocol' and 'what the routes mean' (CIDR included) is a
matter of consensus among parties exchanging a single routing protocol,
not an Internet-wide requirement.
> It's also a of a stretch to call the 1985 change of class D from
> "unused" or "reserved" to the multicast space a redefinition of the
> IP address space.
Under classic IP, class D was defined as unused/reserved;
under multicast IP, class D is now defined as multicast.
That is the purest form of the change of a definition.
While it affects only a portion of all IP packets, it did redefine
the meaning of that portion.
(it redefined the meaning of values of the space, not the partitioning
of the space).
Joe
