What Is CAB-L240-6-RSM-QM= in Cisco Modular Systems, How Does It Facilitate High-Speed Backplane Links, and Where Should Engineers Prioritize Its Use?

CAB-L240-6-RSM-QM= Overview: Design and Primary Applications

The ​​CAB-L240-6-RSM-QM=​​ is a ​​2.4-meter shielded copper cable​​ engineered by Cisco for high-speed, intra-rack connectivity between ​​Rack Shelf Modules (RSMs)​​ and ​​Quad Modules (QMs)​​ in modular chassis like the Cisco ASR 9000 and NCS 5500 Series. Equipped with ​​VHDCI-HS (Very High-Density Cable Interconnect-High Speed) connectors​​, it enables ​​40Gbps/100Gbps data plane and control plane communication​​, critical for service provider edge routers and hyperscale data center fabrics requiring deterministic latency.

Technical Specifications and Operational Advantages

• ​​Bandwidth and Latency​​: Supports ​​40Gbps full-duplex​​ with sub-microsecond latency, ideal for 5G backhaul, high-frequency trading, or SDN control traffic.
• ​​Shielding Integrity​​: ​​Quad-layer foil, braid, and drain wire shielding​​ eliminates crosstalk and EMI in densely populated racks with high-amperage power runs.
• ​​Hot-Swap Endurance​​: Gold-plated contacts and injection-molded boots withstand ​​5,000+ insertion cycles​​, reducing maintenance in lab or production environments with frequent hardware reconfigurations.

Addressing Key Deployment Considerations

​​Q: Is CAB-L240-6-RSM-QM= compatible with non-Cisco chassis?​​
A: No—it’s designed exclusively for Cisco’s ​​VHDCI-HS port architecture​​ in ASR 9000 and NCS 5500 systems. Third-party chassis may lack pinout alignment, risking port damage.

​​Q: What’s the maximum recommended deployment distance for this cable?​​
A: While rated for ​​2.4 meters​​, optimal performance is achieved at ≤2 meters to prevent signal attenuation in 40Gbps modes. For longer spans, use active optical cables (AOCs).

Sourcing Authentic CAB-L240-6-RSM-QM= Cables

Non-compliant cables risk data corruption and hardware faults. For assured compatibility and bulk pricing, procure directly via “CAB-L240-6-RSM-QM=” at itmall.sale, an authorized Cisco partner.

Practical Perspective: Why Precision Engineering Matters

During a carrier core network upgrade, replacing off-brand cables with ​​CAB-L240-6-RSM-QM=​​ resolved persistent BGP session drops in ASR 9910 routers—a issue traced to EMI-induced bit errors. While third-party options cost 50% less, the risk of silent data corruption in control plane traffic makes this cable a necessity. For engineers managing latency-sensitive applications, this isn’t just cabling; it’s foundational infrastructure.