On Nov 20, 2013, at 12:05 PM, Dave Crocker <dhc@xxxxxxxxxxxx> wrote: > People have done all manner of closed email services, over the years. They work in small groups of folk, who have no interest in dealing with the larger world. Serendipitous contact by new and unknown folk is an integral part of living in the real world. Allow in new folk easily and you allow in bad folk too. FoaF and common interest groups are great ways to deal with those kinds of contacts. Anyway, we should stop arguing about this on the IETF mailing list. If I had time I'd be hacking on this, not talking about it.