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Re: CVS commit: src

nia <> writes:

> On Wed, May 25, 2022 at 08:42:20AM -0400, Greg Troxel wrote:
>> I was really surprisd that we had mbone applications in base; to me,
>> that would mean things like vic and vat.
>> This is not about about MBONE; it's about multicast routing.  The mbone
>> was an overlay network to connect local multicast islands, and operated
>> in the 90s.
> Interesting, thanks.
>> Separately from the mbone, I have used multicast routing support in
>> NetBSD across connected local networks.
>> (Arguably map-mbone is misnamed; it really isn't about the mbone per se
>> but about whatever multicast network is available.  But that's just a
>> historical note.)
> Is the name situation same for the category in pkgsrc?

Slightly, but not really.  Back then, there was multicast routing, and
then there was the mbone project for wide-area multicast because the
internet didn't yet support it like it eventually would (reality ended
up different).  Things like vic and vac came out of the research effort
that was associated with mbone deployment, and that's why I mentioned
them as "mbone".  It's true they work on multicast rather than mbone,
and thus arguably we should rename the category, but in pkgsrc we don'd
do that.  I'd say the pkgsrc name is wrong though.

>> I don't object to a default-on MK knob; having knobs to make base
>> smaller seems entirely reasonable.
>> I would suggest "multicast" as a word rather than mbone, as what this
>> knob does is remove user-space support for IP multicast routing.
>> Someone who understands the history would not expect mrouted to vanish
>> by disabling mbone.
> All of these applications depends on the "MROUTING" kernel option,
> it seems, which is mostly default-off, except for a few (tending
> on the more obscure side) kernel configs. I wonder if anyone
> knows the history there.

I'm not really sure why MROUTING is default off, but I think BSD
tradition is that the user-space tools are present even for kernel
options that are off, and that was ok because ~everybody built their own
kernel anyway, but almost nobody rebuilt userland.  The disk space for
these programs was small, and kernel RAM was a big deal, if you set the
wayback machine to a VAX with 1MB of RAM and a 100 MB disk, or 8MB and
250 MB.  I'm fuzzy on the exact numbers, but I'm sure kernel RAM usage
was a much bigger deal than disk.

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