D-Link DES-1005D - Manual (Page 24)

12
Port Speed & Duplex Mode
After plugging the selected cable to a specific port, the
system uses auto-negotiation to determine the transmission
mode for any new twisted-pair connection:
If the attached device does not support auto-
negotiation or has auto-negotiation disabled, an auto-
sensing process is initiated to select the speed and set the
duplex mode to half-duplex.