D-Link DMC-700SC - Media Converter - External User Manual page 7

"Off" for auto-negotiation mode.
Note: Be sure the opposite end is using the same setting (forced or Auto-negotiation).
When connecting two converters both MUST be set to forced mode.
Switch 2: LLR
When the switch is turned to "On", it means that LLR is
enabled and "Off" for disabled.
Note: When connecting two converters, only enable the LLR function on one device.
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