[homenet] after the meeting comments on draft-ietf-homenet-front-end-naming-delegation-07

[Denis Ovsienko <[e-mail]>]

Hello group.

What I was trying to say at the WG meeting was the following. Looking at the slide with the red arrow between a DNS server in the home network and a DNS server somewhere on the Internet, the following scenario immediately came to my mind.

1. A home network is connected to the Internet through an ISP A. Everything is synchronous and works.
2. The link to ISP A fails.
3. For the next month the home network remains half time disconnected and half time connected through ISP B. Regardless of the Internet reachability, devices come and go, and the network tries to update its zone.
4. The link to ISP A is restored and works for the next three months.
5. The user occasionally connects to ISP B in parallel, as a matter of habit.
6. Go to 2.

Now, given the suggestion that the ISP maintains the zone, it would make sense to think what happens when the ISP's copy is no longer updated and the home network copy has changed. I have briefly looked through the I-D and have not found anything that would explicitly make sure that the zone cannot go split-brain. And if it goes split-brain, will it necessarily synchronize afterwards with no human intervention? Maybe those provisions are there, but I did not see them, in that case please disregard the comment.

Feel free to use this input to improve the document, if it gives you any new ideas.

-- 
    Denis Ovsienko