Arista QSFP-100G-ERL4 Compatible 100GBASE-ER4 Lite QSFP28 40km Module

EdgeOptic's QSFP-100G-ERL4 compatible is an Arista coded 100GBASE-ER4 Lite QSFP28 transceiver built on the 100G-QSFP28-40 hardware platform. The module ships pre-programmed with the Arista EEPROM values for the QSFP-100G-ERL4 ordering code, so the optic identifies on EOS as the OEM transceiver. Arista names this part QSFP-100G-ERL4; Cisco and Juniper write the suffix as ER4L on their equivalent ER4 Lite parts. The letter order is a vendor-naming convention, not a different optical class.

Optically the module conforms to the 100GBASE-ER4 Lite specification. Four LAN-WDM channels at 1295.56, 1300.05, 1304.58 and 1309.14 nm each carry 25.78125 Gbps NRZ, multiplexed onto one duplex LC single-mode fiber pair. The transmitter is an EML array; the receiver is an APD array, providing the additional sensitivity that distinguishes ER4 Lite from a standard LR4 PIN-receiver build. ER4 Lite is not an IEEE 802.3ba or 802.3bm subclause and is not a 100G Lambda MSA grade; it is a generic 100GBASE-ER4 Lite specification used across vendor catalogs.

Reach is 40km on G.652 SMF with host RS-FEC enabled and 30km on the same fiber without FEC. Optical budget is 22 dB with FEC, 18 dB without. Host-side FEC is the gating requirement for the 40km reach; the optic itself is transparent to FEC and contains no internal FEC engine. Engineers planning metro or DCI links between 30 and 40km should confirm the host port has RS-FEC available on the 100GE MAC and verify both ends match during commissioning. Without FEC the link will close at distances up to 30km on plant operating near typical 0.35 dB/km attenuation.

The QSFP-100G-ERL4 is supported on Arista 7280R3, 7500R3 and 7800R3 series platforms with QSFP28 ports. Verify the optic against the Arista Transceiver Compatibility Guide for your specific switch model, port group and EOS release before deployment, as supported optic lists vary by hardware family and firmware revision. Arista EOS validates transceiver vendor identifiers on insertion; with the Arista coded EEPROM the module shows up as a recognized optic in standard EOS transceiver inventory output.

QSFP28 MSA SFF-8665 and SFF-8636 management compliance covers the electrical and software interfaces. DDM/DOM telemetry exposes per-lane TX and RX optical power, module temperature, supply voltage and laser bias current to the host for both EOS CLI inspection and streaming-telemetry collection. The duplex LC connector accepts standard SMF patch cords. Power draw is bounded at 4.5 W maximum; the commercial 0 to +70 degC case-temperature range covers central-office and metro POP environments. Connector hygiene matters at ER4 Lite reach budgets; inspect and clean both end-faces before turn-up to avoid attenuation that erodes the FEC margin.

Backed by 15+ years of EdgeOptic compatibility engineering across vendor optical platforms. Ships next business day from EU stock with a lifetime warranty. For BOM verification or volume pricing, contact our sales team.