On 13 Aug 2015, at 18:50, Nick Mathewson nickm@alum.mit.edu wrote:
On Wed, Aug 12, 2015 at 5:34 PM, nusenu nusenu@openmailbox.org wrote:
from today's measurement meeting:
15:00:20 <virgil> karsten: I've decided I'm going to fix the definition of median 15:00:26 <virgil> in the tor sourcecode 15:00:36 <karsten> virgil: is it broken? 15:00:53 <karsten> or just not specified as clearly as it should be? 15:01:01 <virgil> for ordered list {a,b,c,d}, it returns b instead of (b+c)/2. 15:01:24 <karsten> yes. maybe that's for a reason (which I don't know). 15:01:40 <virgil> I look forward to hearing this reason when my patch is rejected. 15:01:41 <karsten> like, using value (b+c)/2 would break for some reason, whereas any of a, b, c, d would be fine. 15:01:45 <Sebastian> you cannot do that 15:01:51 <Sebastian> without breaking Tor's voting 15:02:21 <Sebastian> Tor's specification requires low median for a bunch of directory stuff
I'd be interested in the reason as well.
The correct fix here is to update the code documentation to define the functions as returning the low-median, and to update dir-spec.txt to say so too. I'd accept documentation patches like that.
The documentation for the code already says that. The spec could be updated to say low-median consistently, tho.
Cheers Sebastian