IMC Networks IE-MiniFiberLinX-II Operation Manual page 41

Mode Three - Transparency with Tagged Management
This mode will pass all tagged and untagged customer traffic. Management traffic
must be tagged. It does not add or remove tags.
Mode Four - Transparency with Extra Tagging (or Q-in-Q)
This mode is designed to either pass all customer traffic with the defined extra tag (Q-
in-Q) or add and remove the defined extra tag (Q-in-Q) on all customer traffic.
Management traffic can be tagged or untagged.
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