[tor-commits] [torspec/master] Changes for proposal 215

[nickm at torproject.org]

commit fc8a6f0da0c79783fe48076243970fa6700c4f7c
Author: Nick Mathewson <nickm at torproject.org>
Date:   Mon Aug 18 10:37:31 2014 -0400

    Changes for proposal 215
    
    13 is now the minimum consensus method; 1 is no longer required.
---
 dir-spec.txt |   15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/dir-spec.txt b/dir-spec.txt
index 109215a..71ec34b 100644
--- a/dir-spec.txt
+++ b/dir-spec.txt
@@ -1303,9 +1303,8 @@
         [At most once for votes; does not occur in consensuses.]
 
         A space-separated list of supported methods for generating
-        consensuses from votes.  See section 3.8.1 for details.  If this
-        line is present, method "1" MUST be included.  Absence of the
-        line means that only method "1" is supported.
+        consensuses from votes.  See section 3.8.1 for details.  Absence of
+        the line means that only method "1" is supported.
 
     "consensus-method" SP Integer NL
 
@@ -2104,7 +2103,7 @@
 
    To achieve this, authorities list in their votes their supported methods
    for generating consensuses from votes.  Later methods will be assigned
-   higher numbers.  Currently recognized methods:
+   higher numbers.  Currently specified methods:
      "1" -- The first implemented version.
      "2" -- Added support for the Unnamed flag.
      "3" -- Added legacy ID key support to aid in authority ID key rollovers
@@ -2127,7 +2126,13 @@
    Before generating a consensus, an authority must decide which consensus
    method to use.  To do this, it looks for the highest version number
    supported by more than 2/3 of the authorities voting.  If it supports this
-   method, then it uses it.  Otherwise, it falls back to method 1.
+   method, then it uses it.  Otherwise, it falls back to the newest consensus
+   method that it supports (which will probably not result in a sufficiently
+   signed consensus).
+
+   All authorities MUST support method 13; authorities SHOULD support more
+   recent methods as well.  Authorities SHOULD NOT support or advertise
+   support for any method before 13.
 
    (The consensuses generated by new methods must be parsable by
    implementations that only understand the old methods, and must not cause