Arista QDD-400G-FR4 Compatible 400GBASE-FR4 QSFP-DD Transceiver

EdgeOptic's QDD-400G-FR4 compatible is an Arista-coded 400GBASE-FR4 QSFP-DD transceiver, programmed with Arista-recognized EEPROM so EOS accepts the module on insertion without unsupported-transceiver alerts. Same pinout, same optical envelope as Arista's original part, with the EEPROM programmed for Arista platforms specifically. Don't confuse it with the Juniper QDD-400G-FR4: the bare SKU string is identical between vendors, but the EEPROM is not. Specify Arista when ordering so the correct EEPROM image is programmed at build.

Four CWDM wavelengths at 1271, 1291, 1311, and 1331 nm, multiplexed onto a single duplex LC pair. PAM4 modulation at 53.125 GBaud per lane for 400 Gb/s aggregate. EML transmitters per wavelength channel, PIN photodiode receivers on the inbound side. TX -3.3 to +3.5 dBm per lane, RX sensitivity -7.3 dBm. The 4 dB optical budget supports a 2 km OS2 span with margin for patch panels and splices. Power under 10 W. Full 400GBASE-FR4 specifications cover the rest.

Works on Arista 7050X4, 7060X4, 7060X5, and 7800R3 platforms, all of which carry QSFP-DD ports for 400G client connectivity. Verify QDD-400G-FR4 support against Arista's transceiver compatibility matrix and your specific EOS release at arista.com/en/support. Older Arista platforms like the 7050CX3 are 100G-era hardware and have no QSFP-DD slots. KP4 RS-FEC is required at 400G; EOS enables it by default on QSFP-DD interfaces.

Same part number, two different vendors. Both Arista and Juniper sell a QDD-400G-FR4 under the same literal SKU string. Optically the modules are identical (400GBASE-FR4, IEEE 802.3cu, same wavelength plan), but the EEPROM is vendor-specific. An Arista-coded module won't pass IDPROM checks on Junos; a Juniper-coded module won't pass on EOS. Getting the wrong vendor coding logs an unsupported-transceiver alert and the link stays down. Specify the switch vendor at order time.

EOS treats the Arista-coded compatible as a recognized transceiver, so DOM is accessible through standard show interfaces transceiver commands. Per-lane TX and RX optical power, case temperature, supply voltage, and laser bias current are exposed on QSFP-DD interfaces, which helps isolate a specific CWDM wavelength when debugging a degraded link. Conforms to IEEE 802.3cu, 100G Lambda MSA 400G-FR4, QSFP-DD MSA, and CMIS 4.0. Class 1 laser safe per IEC 60825-1, CE and RoHS certified, 0 to 70 °C.

Backed by 15+ years of EdgeOptic compatibility engineering across vendor optical platforms. Made to order with a 2-week lead time and lifetime warranty included. For volume pricing or platform-specific EEPROM coding, contact our sales team.