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.

Arista Networks Compatibility and Factory Testing

The module is checked for host recognition as QSFP-40G-LR4-20, link establishment and diagnostic reporting. Physical cage fit alone is not treated as evidence of compatibility. Equipment model, hardware revision and software release can be reviewed before dispatch where platform behavior is uncertain.

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. During commissioning, record the host diagnostic readings after the link has stabilized and compare them with those limits. DOM values are useful operational indicators, but they do not replace calibrated optical measurements when a link is marginal. Investigate unexpected loss through connector inspection, cleaning and a channel measurement before replacing the module. 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.

Structured Fiber Pathways and Serviceability

Treat the transceiver as part of the complete channel. Follow the intended patch-panel route, maintain bend control and leave service access around the port. Confirm connector polish and fiber type at every mated pair; a documented service allowance is preferable to excess slack concealed inside a rack. For this model, the principal parameters are data rate 41.2Gbps (4x 10.3Gbps), wavelength 1310nm, rated reach 20km.

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.

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.

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