Re: Running code (Was: I-D Action: draft-ietf-6man-ipv6only-flag-03.txt)

[Brian E Carpenter <[e-mail]>]

On 2018-10-29 08:31, Manfredi (US), Albert E wrote:
...
> What you seem to be missing, all this IPv6 flag means is "no IPv4 packets transit THIS router."

No, it still doesn't mean that. It means, if and only if all IPv6 default routers
send it, that the network manager has *decided* that there should be no IPv4
traffic on the link.

> That's the extent of it. You seem to be attributing a lot more to the flag than it actually intends.

Frankly Bert, you seem to be ignoring the words in the draft.

On 2018-10-29 10:47, Manfredi (US), Albert E wrote:
...
> The flag adds very little indeed.

It adds the *intention* of the network manager that there should be no
IPv4 traffic on the link. Of course, a host can decide to ignore that
intention, and protocol police in the form of layer 2 filters may enforce
the intention.

Personally, if I was in a position to write the heuristic that a host
uses, I would use this flag as a heavily weighted input that would
either prevent any IPv4 activity whatever, or increase the backoff
timers to a very large value, since it's a clear signal that, for example,
mDNS over IPv4 is simply not available.

   Brian