diff --git a/doc/spec/dir-spec.txt b/doc/spec/dir-spec.txt
index a7b2e5d803..1acfb46688 100644
--- a/doc/spec/dir-spec.txt
+++ b/doc/spec/dir-spec.txt
@@ -1115,8 +1115,12 @@ $Id$
    minutes, 60 minutes, 90 minutes).  Voting intervals SHOULD be chosen to
    divide evenly into a 24-hour day.
 
-   Authorities MUST take pains to ensure that their clocks remain accurate,
-   for example by running NTP.
+   Authorities SHOULD act according to interval and delays in the
+   latest consensus.  Lacking a latest consensus, they SHOULD default to a
+   30-minute Interval, a 5 minute VotingDelay, and a 5 minute DistDelay.
+
+   Authorities MUST take pains to ensure that their clocks remain accurate
+   within a few seconds.  (Running NTP is usually sufficient.)
 
    The first voting period of each day begins at 00:00 (midnight) GMT.  If
    the last period of the day would be truncated by one-half or more, it is
diff --git a/src/or/config.c b/src/or/config.c
index 30ead7f400..a12ca86ef6 100644
--- a/src/or/config.c
+++ b/src/or/config.c
@@ -271,7 +271,6 @@ static config_var_t _option_vars[] = {
   VAR("V1AuthoritativeDirectory",BOOL, V1AuthoritativeDir,   "0"),
   VAR("V2AuthoritativeDirectory",BOOL, V2AuthoritativeDir,   "0"),
   VAR("V3AuthoritativeDirectory",BOOL, V3AuthoritativeDir,   "0"),
-  /* XXXX020 check these for sanity. */
   VAR("V3AuthVotingInterval",INTERVAL, V3AuthVotingInterval, "1 hour"),
   VAR("V3AuthVoteDelay",     INTERVAL, V3AuthVoteDelay, "5 minutes"),
   VAR("V3AuthDistDelay",     INTERVAL, V3AuthDistDelay, "5 minutes"),
@@ -1090,7 +1089,9 @@ options_act(or_options_t *old_options)
       if (dns_reset())
         return -1;
     }
-    /* XXXX020 init_keys() again if v3authoritativedir is newly set. */
+
+    if (options->V3AuthoritativeDir && !old_options->V3AuthoritativeDir)
+      init_keys();
   }
 
   /* Check if we need to parse and add the EntryNodes config option. */
@@ -2999,6 +3000,23 @@ options_validate(or_options_t *old_options, or_options_t *options,
     }
   }
 
+  if (options->V3AuthVoteDelay + options->V3AuthDistDelay >=
+      options->V3AuthVotingInterval/2) {
+    REJECT("V3AuthVoteDelay and V3AuthDistDelay must be no more than half "
+           "V3AuthVotingInterval");
+  }
+  if (options->V3AuthNIntervalsValid < 2) {
+    REJECT("V3AuthNIntervalsValid must be at least 2.");
+  }
+
+  if (options->V3AuthVotingInterval < 300) {
+    REJECT("V3AuthVotingInterval is insanely low.");
+  } else if (options->V3AuthVotingInterval > 24*60*60) {
+    REJECT("V3AuthVotingInterval is insanely high.");
+  } else if (((24*60*60) % options->V3AuthVotingInterval) != 0) {
+    COMPLAIN("V3AuthVotingInterval does not divide evenly into 24 hours.");
+  }
+
   if (rend_config_services(options, 1) < 0)
     REJECT("Failed to configure rendezvous options. See logs for details.");
 
diff --git a/src/or/dirvote.c b/src/or/dirvote.c
index 0846772eda..760945c2d2 100644
--- a/src/or/dirvote.c
+++ b/src/or/dirvote.c
@@ -923,7 +923,7 @@ networkstatus_get_detached_signatures(networkstatus_vote_t *consensus)
     {
       char sk[HEX_DIGEST_LEN+1];
       char id[HEX_DIGEST_LEN+1];
-      if (!v->signature) // XXXX020 || !v->good_signature)
+      if (!v->signature || v->bad_signature)
         continue;
       ++n_sigs;
       base16_encode(sk, sizeof(sk), v->signing_key_digest, DIGEST_LEN);
@@ -1038,9 +1038,15 @@ dirvote_get_start_of_next_interval(time_t now, int interval)
 
   next = midnight_today + ((now-midnight_today)/interval + 1)*interval;
 
+  /* Intervals never cross midnight. */
   if (next > midnight_tomorrow)
     next = midnight_tomorrow;
 
+  /* If the interval would only last half as long as it's supposed to, then
+   * skip over to the next day. */
+  if (next + interval/2 > midnight_tomorrow)
+    next = midnight_tomorrow;
+
   return next;
 }
 
@@ -1061,9 +1067,11 @@ static struct {
 void
 dirvote_recalculate_timing(time_t now)
 {
-  /*XXXX020 call this when inputs may have changed. */
+  /* XXXX020 call this when inputs may have changed (i.e., whenver we get a
+   * fresh consensus.) */
   int interval, vote_delay, dist_delay;
   time_t start;
+  time_t end;
   networkstatus_vote_t *consensus = networkstatus_get_latest_consensus();
 
   memset(&voting_schedule, 0, sizeof(voting_schedule));
@@ -1074,18 +1082,27 @@ dirvote_recalculate_timing(time_t now)
     vote_delay = consensus->vote_seconds;
     dist_delay = consensus->dist_seconds;
   } else {
-    /* XXXX020 is this correct according the the spec? */
-    /* XXXX020 drop this back down to 60 minutes, or whatever the spec says. */
+    /* XXXX020 drop this back down to 30 minutes. */
     interval = 1200;
     vote_delay = dist_delay = 300;
   }
 
+  tor_assert(interval > 0);
+
+  if (vote_delay + dist_delay > interval/2)
+    vote_delay = dist_delay = interval / 4;
+
   start = voting_schedule.interval_starts =
     dirvote_get_start_of_next_interval(now,interval);
+  end = dirvote_get_start_of_next_interval(start+1, interval);
+
+  tor_assert(end > start);
+
   voting_schedule.voting_ends = start - vote_delay;
   voting_schedule.voting_starts = start - vote_delay - dist_delay;
 
-  voting_schedule.discard_old_votes = start + 300; /* XXXX020 */
+  voting_schedule.discard_old_votes = start +
+    ((end-start) - vote_delay - dist_delay)/2 ;
 }
 
 /** DOCDOC */
diff --git a/src/or/or.h b/src/or/or.h
index 2ab1d7b0d6..63fe33d6e3 100644
--- a/src/or/or.h
+++ b/src/or/or.h
@@ -2067,12 +2067,14 @@ typedef struct {
    * if we are a cache).  For authorities, this is always true. */
   int DownloadExtraInfo;
 
-  /** The length of time that we think a consensus should be  */
+  /** The length of time that we think a consensus should be fresh. */
   int V3AuthVotingInterval;
+  /** The length of time we think it will take to distribute votes */
   int V3AuthVoteDelay;
+  /** The length of time we think it will take to distribute signatures */
   int V3AuthDistDelay;
+  /** The number of intervals we think a consensus should be valid. */
   int V3AuthNIntervalsValid;
-
 } or_options_t;
 
 /** Persistent state for an onion router, as saved to disk. */