Arista Networks QSFP-40G-LR4-20 Compatible 40G QSFP+ ELR4 Transceiver Module

Product Highlights

• Compatible alternative to Arista Networks QSFP-40G-LR4-20
• 40G connectivity at 41.2Gbps (4x 10.3Gbps)
• Optical wavelength: 1310nm
• Specified reach: 20km
• Duplex LC / SMF interface
• Operating temperature: 0 to 70°C(32 to 158°F)
• Factory compatibility verification and optical performance testing before shipment

Specifications

Applications and Optical Link Design

Use this module for equipment interconnection over the specified single-mode fiber plant, including enterprise backbone, campus, metro or data-center interconnect links according to its rated distance. Confirm that both ends use the same optical standard and wavelength plan, and allow for connector, splice and patch-panel loss within the stated power budget.

Before deployment, check the host port type, supported data rate and firmware requirements. The 40G interface configuration must match the remote equipment; sharing a QSFP+ housing alone does not make two transceiver types interoperable.

Before commissioning, measure the complete single-mode channel against the stated budget for 20km. Inspect every Duplex LC connection and record diagnostic power where supported. Both ends must agree on rate, wavelength and optical standard.

Optical Acceptance, Diagnostics and Handling

For this model, the specified transmit-power range is -4.5~2.3dBm; receiver sensitivity is <-12.5dBm; the stated optical power budget is 8dB. A sound acceptance record includes link state, diagnostic temperature, supply voltage and transmit or receive levels where the host exposes them. Compare the readings with the stated ranges rather than treating any received light as proof of adequate margin. Persistent alarms or borderline values should trigger an end-face and complete-channel inspection. Before every insertion, keep dust caps in place until the patch lead is ready, avoid touching the optical end face and use an appropriate inspection and cleaning procedure. Do not look into an active optical interface.

Mixed-Vendor Network Operation

A mixed-vendor optical link should be documented at both ends, not treated as one generic connection. Confirm which OEM identity each host expects and whether both ends use the same wavelength plan and optical standard. Related links locate equivalent hardware, but brand-specific identification must still be selected independently. For this model, the principal parameters are data rate 41.2Gbps (4x 10.3Gbps), wavelength 1310nm, rated reach 20km.

Arista Networks Compatibility and Factory Testing

Compatibility testing for QSFP-40G-LR4-20 combines identification with a live link and available transmit, receive and alarm information. Connector condition is inspected separately. Equipment model, hardware revision and software release can be reviewed before dispatch where platform behavior is uncertain.

Ordering Information

Use QSFP-40G-LR4-20 as the compatibility cross-reference and QSFP-ELR4-40G as the HT ordering identity. Keep other reaches or wavelength directions on separate order lines. Neutral labels, customer packaging and project-specific compatibility review are available on request.

Quality Assurance and Packaging

Before packing, the module receives interface inspection, identification and link checks. Protective packaging avoids pressure on the connector and latch. Customer references, rack groups and project packing lists can be added for volume orders.

Frequently Asked Questions

Shipping and Lead Time

Standard configurations normally ship within one to three working days, with production lead times confirmed for larger quantities. International courier, air freight and sea freight are available; customer courier accounts and nominated forwarders are accepted.