On 18 Apr 2014, at 19:52, Nick Mathewson nickm@alum.mit.edu wrote:
Imo we _should_ check through the code for things related to the Named flag, though, back through 0.2.3 or maybe 0.2.2. Reasons:
- Private networks never worked very well with older tors.
- Maybe there's some piece of obscure functionality that breaks
without naming authorities which we never tested on a private network.
Ok, here's round two then, with the Design section updated:
Filename: xxx-kill-named-flag.txt Title: Stop assigning (and eventually supporting) the Named flag Authors: Sebastian Hahnn Created: 10 April 2014 Target: 0.2.5 Status: Draft
1. Intro and motivation
Currently, Tor supports the concept of linking a Tor relay's nickname to its identity key. This happens automatically as a new relay joins the network with a unique nickname, and keeps it for a while. To indicate that a nickname is linked to the presented identity, the directory authorities vote on a Named flag for all relays where they have such a link. Not all directory authorities are currently doing this - in fact, there are only two, gabelmoo and tor26.
For a long time, we've been telling everyone to not rely on relay nicknames, even if the Named flag is assigned. This has two reasons: First off, it adds another trust requirement on the directory authorities, and secondly naming may change over time as relays go offline for substantial amounts of time.
Now that a significant portion of the network is required to rotate their identity keys, few relays will keep their Named flag. We should use this chance to stop assigning Named flags.
2. Design
None so far, but we should review older-but-still-supported Tor versions (down to 0.2.2.x) for potential issues. In theory, Tor clients already support consensuses without Named flags, and testing in private Tor networks has never revealed any issues in this regard, but we're unsure if there might be some functionality that isn't typically tested with private networks and could get broken now.
3. Implementation
The gabelmoo and tor26 directory authorities can simply remove the NamingAuthoritativeDirectory configuration option to stop giving out Named flags. This will mean the consensus won't include Named and Unnamed flags any longer. The code collecting naming statistics is independent of Tor, so it can run a while longer to ensure Naming can be switched on if unforeseen issues arise.
Once this has been shown to not cause any issues, support for the Named flag can be removed from the Tor client implementation, and support for the NamingAuthoritativeDirectory can be removed from the Tor directory authority implementation.
4. Open questions
None.