Edimax NS-2501 User Manual page 38

Maximum The maximum number of active torrents that can be downloaded at
number of active the same time. If you add more download items, some items have to
downloads wait in turn.
Maximum The maximum number of connections can be used to download a BT
concurrent download item at the same time.
connection
number per
torrent
Enable DHT network would let the BT have a chance to find more
DHT network
peers to download even when no tracker servers are available.
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