Yarmouth Port, MA
|reply to funchords |
Re: Comcast is using Sandvine to manage P2P Connections
It's been over 3 months since my original post, so I decided to see if the numbers or behaviors had changed.
The numbers did not change, much. In May, 39% of my BitTorrent connections were killed by the RST flag, but I was still able to seed a torrent at my preferred speed (16 KB/s). Today that number is 46% killed, and still able to seed a torrent at my preset upload limit speed (16 KB/s).
What did change is the behavior toward BitTorrent's standard DHE encrypted connections: Surprisingly, none were dropped! It was only yesterday or the day before that I noted encrypted connections were still being killed by RST, so this is new behavior for me. This could be due to policy parameters such as time-of-day, level of global or individual use, or localized adjustments -- so your milage may vary.
The test method:
1. Start a BitTorrent client performing an upload (seeding) to an established swarm.
2. Wait 5 minutes to allow connections and speeds to stabilize.
3. Record the starting number of connections and resets reported by "netstat -s" or start the batch file (see »How to test how many connections are being reset by RST pack for details).
4. Wait 5 minutes.
5. Record the ending number of connections and resets, and determine the amount that took place during the test (or obtain the numbers from the batch file).
I used the above method on the same small (25-30 peer, 4 seed) swarm, using uTorrent 1.7.2.
No encryption ... 34 out of 73 reset (46%)
Encryption enabled (with fallback) ... 5 out of 20 reset (25%)
Encryption forced (no fallback) ... 0 out of 17 reset ( 0%)