Re: Add ARP to INET or require ND6

[John Nemeth <jnemeth%cue.bc.ca@localhost>]

On May 4,  6:34pm, Mouse wrote:
}
} > While adding the IN_IFF_TENTATIVE functionality and friends it was
} > pointed out that ARP is optional with INET.
} > The argument at the time being why pay for ARP if there are no real
} > interfaces?
} 
} Seems to me it's more "why pay for ARP if there are no ARP-using
} interfaces?", but perhaps that's what "real" actually means there.
} (There are plenty of ways to transport IP packets that don't need ARP,
} starting with PPP.)
} 
} > However, NS/NA (the ARP equivalent of IPv6) is not optional with
} > INET6, it's forced.
} 
} > So the burning question is this:
} > Should we turn NS/NA into an option or remove the ARP option?
} 
} I'd argue in favour of the former.

     The mistake here, which is one made by many people, is in
thinking of IPv6 as IPv4 with larger addresses.  It's not, it is
a distinct protocol.  So, I would argue for doing neither.  IPv4
is not IPv6.  NS/NA is integral to IPv6; ARP is not integral to
IPv4.

} > I'm in favour of the latter as I would find it hard to test patches
} > for the former given my restricted hardware set.
} 
} I don't think "I can't test option 1" is a good driver for technical

     I have to agree.  This would set an extremely bad precedence.

} decisions.  I'd prefer to make it an option, comment in the config
} files that INET6 without NS/NA is untested beyond making sure it
} builds, with the comment to be removed if/when it gets tested.

     As NS/NA is integral to IPv6, this would be a silly thing to do.

}-- End of excerpt from Mouse