Fortinet FN-TRAN-QSFPDD-DR4+ QSFP-DD Transceiver

The extended-reach DR4+ ordering identity

FN-TRAN-QSFPDD-DR4+ is Fortinet's 400 GE QSFP-DD module for a four-channel parallel single-mode link up to 2 km. Fortinet specifies an MPO-12 connector and 1311 nm wavelength for this exact plus-suffixed order.

Keep the plus suffix through procurement

The separate FN-TRAN-QSFPDD-DR4 item has a 500 m published range. Retain DR4+ in the quotation, packing list and module inventory so the extended-reach order is not normalized into the shorter-range model. The manufacturer's protocol row labels both as 400G-Base-DR4; the order code and reach distinguish them.

A 2 km range does not make it an FR4 replacement

The same datasheet lists FN-TRAN-QSFPDD-FR4 at 2 km but with duplex LC, while DR4+ uses the parallel MPO-12 path. Select the optical architecture from the existing fiber plant and matching endpoint, not from distance alone. Confirm platform and software support for the exact transceiver before approving a substitution.

Power and receiving checks

The DR4+ specification lists power dissipation below 14 W and a 0°C to 70°C operating range. Check the host's module support and thermal constraints, then inspect the delivered label and connector arrangement. Retain the cable-route record and commissioning results, including link state, supported optical diagnostics and error counters.

Fortinet Transceivers: exact specifications and ordering rows, pages 8 and 14