diff options
| -rw-r--r-- | proposals/151-path-selection-improvements.txt | 25 |
1 files changed, 14 insertions, 11 deletions
diff --git a/proposals/151-path-selection-improvements.txt b/proposals/151-path-selection-improvements.txt index 94e964b..af17c4d 100644 --- a/proposals/151-path-selection-improvements.txt +++ b/proposals/151-path-selection-improvements.txt @@ -89,17 +89,20 @@ Implementation We attempt to detect both network connectivity loss and drastic changes in the timeout characteristics. - If more than MAX_RECENT_TIMEOUT_RATE (80%) of the past - RECENT_CIRCUITS (20) time out, we assume the network connection - has changed, and we discard all buildtimes history and compute - a new timeout by estimating a new Pareto curve using the - position on the Pareto Quartile function for the ratio of - timeouts. - - Network connectivity loss is detected by recording a timestamp every - time Tor either completes a TLS connection or receives a cell. If - this timestamp is more than CircuitBuildTimeout*RECENT_CIRCUITS/3 - seconds in the past, circuit timeouts are no longer counted. + We assume that we've had network connectivity loss if 3 circuits + timeout and we've recieved no cells or TLS handshakes since those + circuits began. We then set the timeout to 60 seconds and stop + counting timeouts. + + If 3 more circuits timeout and the network still has not been + live within this new 60 second timeout window, we then discard + the previous timeouts during this period from our history. + + To detect changing network conditions, we keep a history of + the timeout or non-timeout status of the past RECENT_CIRCUITS (20) + that successfully completed more than one hop. If more than 75% + of these circuits timeout, we discard all buildtimes history, + reset the timeout to 60, and then begin recomputing the timeout. Testing |