What is Peer Info Exchange / Peer Sharing?
In the old days, when a tracker went offline all the peers downloading/uploading would be stop very quickly. They would then have to wait until the tracker came back online to start downloading/uploading again. With the get_peers/peers extension (Peer Info Exchange), peers can continue to download/upload when a tracker goes offline by broadcasting their peer lists to other peers. This is fantastic for sharing as it strengthens BitTorrents weakest link – trackers. It can also reduce the load on trackers. Private ratio trackers have not always seen this as a good thing however. In the early implimentation of this feature it was possible for private peer lists to be shared with clients on public trackers – which is what got BitComet banned from many trackers (see here). But with the release of BitComet v0.59, the SecureTorrents (‘private’ flag) method of disabling Peer Info Exchange and DHT has been supported, so these features can be disabled within a torrent or in a tracker response (an
