WSP-Q40GLR4L=: High-Performance 40GBase-LR4 QSFP+ Transceiver for Enterprise and Data Center Networks

Component Identification and Functional Role

The ​​WSP-Q40GLR4L=​​ is a Cisco QSFP+ (Quad Small Form-Factor Pluggable) optical transceiver designed for high-speed data transmission in enterprise and data center environments. Based on Cisco’s compatibility matrices and itmall.sale’s technical listings, this module supports ​​40GBase-LR4​​ standards, enabling ​​40 Gbps​​ connectivity over single-mode fiber (SMF) with a reach of up to ​​10 kilometers​​. It is optimized for use in Cisco Nexus and Catalyst switches, providing reliable backbone connectivity for bandwidth-intensive applications like AI/ML workloads, storage replication, and cloud service provider (CSP) interconnects.

Technical Specifications and Design Architecture

Optical Performance and Compatibility

• ​​Data Rate​​: 40 Gbps (4x 10 Gbps lanes via CWDM).
• ​​Wavelengths​​: 1271, 1291, 1311, and 1331 nm (LAN-WDM) with DFB lasers.
• ​​Maximum Distance​​: 10 km over OS2 single-mode fiber (9/125 µm).
• ​​Connector Type​​: Dual LC duplex ports.

Power and Thermal Management

• ​​Power Consumption​​: ≤3.5W typical, compliant with QSFP+ MSA standards.
• ​​Operating Temperature​​: 0°C to 70°C (Commercial) with DOM (Digital Optical Monitoring) support.

Addressing Critical Deployment Concerns

​​Q: Which Cisco devices support this transceiver?​​

• ​​Nexus Series​​: Nexus 9500 (N9K-X9636C-R, N9K-X9636Q-R line cards), Nexus 9300-EX/FX platforms.
• ​​Catalyst Series​​: Catalyst 9400/9500 with C9400-SUP-1/2 supervisors.

​​Q: Can it interoperate with third-party switches?​​

Yes, but ​​Cisco Discovery Protocol (CDP) features​​ are disabled in non-Cisco environments. For OEM compatibility, ensure:

• ​​FEC (Forward Error Correction) Alignment​​: Configure 10GBASE-LR mode on upstream devices.
• ​​Link Negotiation​​: Disable Cisco-proprietary auto-negotiation via no negotiation auto CLI commands.

​​Q: What fiber cabling is required?​​

• ​​OS2 Single-Mode Fiber​​: 9/125 µm core/cladding with LC connectors.
• ​​Attenuation Budget​​: ≤3.5 dB for 10 km reach (≤0.35 dB/km typical).

Enterprise Use Cases and Optimization

Data Center Interconnects (DCI)

• ​​Metro Cluster Extensions​​: Stretch VMware vSAN clusters across sites with <1ms latency (dark fiber).
• ​​Hyperconverged Storage Replication​​: Synchronize Nutanix AHV volumes at 40G line rate.

Enterprise Core Networking

• ​​Campus Backbone Aggregation​​: Link Catalyst 9500 distribution switches with 40G uplinks.
• ​​Video Surveillance Backhaul​​: Stream 4K IP camera feeds (H.265) across multi-building campuses.

Lifecycle Management and Compliance

Firmware and Diagnostics

• ​​Cisco CLI Integration​​: Monitor real-time metrics via show interface transceiver details.
• ​​EOL Planning​​: Cisco’s End-of-Life notice (2025) mandates migration to 100G QSFP28 for future-proofing.

Regulatory Certifications

• ​​FDA/CDRH Compliance​​: Class 1 Laser Product (IEC 60825-1).
• ​​RoHS 3 (EU 2015/863)​​: Compliant with hazardous substance restrictions.

Procurement and Validation

For enterprises requiring validated optics, ​​WSP-Q40GLR4L=​​ is available here. itmall.sale provides:

• ​​Cisco OEM Warranty​​: Includes advanced replacement and TAC support.
• ​​Attenuation Test Reports​​: Pre-shipment validation for plug-and-play deployment.

Strategic Implementation Insights

The ​​WSP-Q40GLR4L=​​ remains a cost-effective solution for 40G deployments but faces obsolescence as hyperscalers shift to 100G/400G architectures. While its 10 km reach suits metro DCI use cases, enterprises should evaluate future bandwidth needs—migrating to QSFP28-100G-LR4 offers 2.5x density but at 3x the cost per port. For existing Nexus 9500 users, this transceiver delivers reliable performance for VM mobility and backup workflows, though its lack of FEC in mixed-vendor setups can limit error resilience. In campus environments, the module’s low power profile justifies retention, but IoT expansion may necessitate upgrading to multi-rate 25/40/100G optics. Ultimately, its value hinges on balancing legacy infrastructure longevity against the accelerating demand for terabit-scale fabrics.