[tor-dev] Prevoting opinions suggested in proposal 147

[Karsten Loesing]

On 1/6/14 9:22 PM, Damian Johnson wrote:
>> I'm not sure what you mean by "specialized DirPort method".  Can you
>> explain that in more detail?
> 
> No doubt I'm missing something basic about either the problem we're
> trying to solve or how votes work. :P
> 
> What I meant by a "specialized DirPort method" was the methods in
> section 4.2 ('/tor/status-vote/current/consensus' and friends). My
> rough guess from the proposal is that the trouble is...
> 
> 1. A new relay publishes their descriptor to a single authority. (?)
> 2. The authority communicates the new descriptor to the rest via their
> v2 document.
> 3. Authorities now have an enumeration of all relays, and generate their vote.
> 
> ... and we don't want #2 to use v2 documents. If that's the case then
> the simple solution seems to be something like...
> 
> 2. When an authority receives a descriptor it forwards it to all the
> other authorities.

That approach scales a lot less than exchanging a single status opinion
document once per voting period.

> My understanding is that votes don't need to precisely match. If a
> descriptor comes in during the window where votes take place then
> that's fine - the majority of authorities won't have it and it simply
> won't be included until the following consensus.

That's correct.  The question is whether we want to fix the situation
that it might take until the next consensus to include a relay that
could have been included in the current consensus.

See also Nick's comment on the other proposal 147 review thread:

> Also, ISTR that Roger told me that this whole proposal didn't actually
> seem to be necessary in practice. I wish I could remember the
> rationale, though.

Personally, I don't feel strongly about either adding prevoting opinions
or living with the 1-hour delay in edge cases.  But the current
situation where we keep publishing v2 statuses is not ideal.

All the best,
Karsten