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Add proposal 150 and proposal 151

svn:r15695
Nick Mathewson преди 16 години
родител
ревизия
f302f23270
променени са 3 файла, в които са добавени 99 реда и са изтрити 0 реда
  1. 4 0
      doc/spec/proposals/000-index.txt
  2. 36 0
      doc/spec/proposals/150-exclude-exit-nodes.txt
  3. 59 0
      doc/spec/proposals/151-path-selection-improvements.txt

+ 4 - 0
doc/spec/proposals/000-index.txt

@@ -72,6 +72,8 @@ Proposals by number:
 147  Eliminate the need for v2 directories in generating v3 directories [OPEN]
 147  Eliminate the need for v2 directories in generating v3 directories [OPEN]
 148  Stream end reasons from the client side should be uniform [OPEN]
 148  Stream end reasons from the client side should be uniform [OPEN]
 149  Using data from NETINFO cells [OPEN]
 149  Using data from NETINFO cells [OPEN]
+150  Exclude Exit Nodes from a circuit [DRAFT]
+151  Improving Tor Path Selection [DRAFT]
 
 
 
 
 Proposals by status:
 Proposals by status:
@@ -85,6 +87,8 @@ Proposals by status:
    134  More robust consensus voting with diverse authority sets
    134  More robust consensus voting with diverse authority sets
    141  Download server descriptors on demand
    141  Download server descriptors on demand
    144  Increase the diversity of circuits by detecting nodes belonging the
    144  Increase the diversity of circuits by detecting nodes belonging the
+   150  Exclude Exit Nodes from a circuit
+   151  Improving Tor Path Selection
  OPEN:
  OPEN:
    120  Shutdown descriptors when Tor servers stop
    120  Shutdown descriptors when Tor servers stop
    121  Hidden Service Authentication
    121  Hidden Service Authentication

+ 36 - 0
doc/spec/proposals/150-exclude-exit-nodes.txt

@@ -0,0 +1,36 @@
+Filename: 150-exclude-exit-nodes.txt
+Title: Exclude Exit Nodes from a circuit
+Version: $Revision$
+Author: Mfr
+Created: 2008-06-15
+Status: Draft
+
+Overview
+
+   Right now, Tor user can manually exclude a node of all the part of
+   circuits created using the directive ExcludeNodes.  
+   This proposal makes this exclusion, less restrictive, allowing to 
+   exclude a node only on the exit part of a circuit.
+
+Motivation
+
+   Helping the integration into vidalia (tor exit branch)or other tools,
+   of features to exclude a country for exit without reducing 
+   circuits possibilities, an privacy.
+   This feature could help people from a country were many sites 
+   are blocked to exclude this country for browsing, giving them a 
+   more stable navigation.
+   Add the possibility for the user to exclude the current used exit
+   node. 
+   
+   
+Implementation
+
+   ExcludeExitNodes is similar to ExcludeNodes except it's only
+   the exit node which is excluded for circuit build.
+   
+   Tor doesn't warn if node from this list is not an exit node.
+
+Security implications:
+
+   Open also possibilities for a future user bad exit reporting.

+ 59 - 0
doc/spec/proposals/151-path-selection-improvements.txt

@@ -0,0 +1,59 @@
+Filename: 151-path-selection-improvements.txt
+Title: Improving Tor Path Selection
+Version:
+Last-Modified:
+Author: Fallon Chen, Mike Perry
+Created: 5-Jul-2008
+Status: Draft
+
+Overview
+
+  The performance of paths selected can be improved by adjusting the
+  CircuitBuildTimeout and the number of guards. This proposal describes
+  a method of tracking buildtime statistics, and using those statistics
+  to adjust the CircuitBuildTimeout and the number of guards.
+
+Motivation
+
+  Tor's performance can be improved by excluding those circuits that
+  have long buildtimes (and by extension, high latency). For those Tor
+  users who require better performance and have lower requirements for
+  anonymity, this would be a very useful option to have.
+
+Implementation
+
+  Learning the CircuitBuildTimeout
+
+    Based on studies of build times, we found that the distribution of
+    circuit buildtimes appears to be a Pareto distribution. The number
+    of circuits to observe (ncircuits_to_observe) before changing the
+    CircuitBuildTimeout will be tunable. From our preliminary
+    measurements, it is likely that ncircuits_to_observe will be
+    somewhere on the order of 1000. The values can be represented
+    compactly in Tor in milliseconds as a circular array of 16 bit
+    integers. More compact long-term storage representations can be
+    implemented by simply storing a histogram with 50 millisecond
+    buckets when writing out the statistics to disk.
+
+  Calculating the preferred CircuitBuildTimeout
+
+    Circuits that have longer buildtimes than some x% of the estimated
+    CDF of the Pareto distribution will be excluded. x will be tunable
+    as well.
+
+  Circuit timeouts
+
+    In the event of a timeout, backoff values should include the 100-x%
+    of expected CDF of timeouts.  Also, in the event of network failure,
+    the observation mechanism should stop collecting timeout data.
+
+  Other notes
+
+    Since this follows a Pareto distribution, large reductions on the
+    timeout can be achieved without cutting off a great number of the
+    total paths.  However, hard statistics on which cutoff percentage
+    gives optimal performance have not yet been gathered.
+
+Issues
+
+  Impact on anonymity