C9300-24UX-E: What Makes It Unique? Multi-Gig
What Is the Cisco Catalyst C9300-24UX-E? Th...
Understanding the CB-LC-LC-SMF20M= Cable
The CB-LC-LC-SMF20M= is a 20-meter single-mode fiber (SMF) optic cable with LC duplex connectors on both ends, engineered for high-speed, long-distance data transmission in Cisco networks. It supports 10G/40G/100G Ethernet and is designed for scenarios requiring minimal signal loss over extended ranges, such as connecting switches across buildings or linking core network layers.
Key Technical Specifications
- Fiber Type: OS2 single-mode (9/125µm), optimized for 1310nm and 1550nm wavelengths.
- Max Distance: 10km at 10G (10GBase-LR) / 40km at 10G (10GBase-ER) with compatible transceivers.
- Connector Quality: Ultra-polished LC connectors with ≤0.2dB insertion loss.
- Jacket Rating: OFNP (plenum-rated) for fire safety in ductwork or ceiling spaces.
CB-LC-LC-SMF20M= vs. Multimode Fiber: Core Differences
| Feature | CB-LC-LC-SMF20M= (SMF) | Multimode Fiber (MMF) |
|---|---|---|
| Distance | 10km+ (10G) | Up to 400m (40G, OM4) |
| Cost | Higher laser transceivers | Lower VCSEL-based optics |
| Application | Metro/core networks | Data center intra-rack links |
| Bandwidth | Virtually unlimited | Limited by modal dispersion |
Why 20 Meters Matters for Single-Mode Deployments
- Inter-Building Connectivity: Links switches in adjacent structures (e.g., campus networks) without exceeding attenuation budgets.
- Avoiding Signal Overkill: Using 10km-capable cables for short runs (<100m) wastes transceiver power, but 20M strikes a balance for mid-range needs.
- Future-Proof Scaling: Supports upgrades to DWDM (Dense Wavelength Division Multiplexing) for terabit-level capacity on existing fiber paths.
For Cisco-certified compatibility, source the cable from authorized suppliers like [“CB-LC-LC-SMF20M=” link to (https://itmall.sale/product-category/cisco/).
Field-Tested Perspective
In a recent deployment for a hospital network, the CB-LC-LC-SMF20M= connected a Nexus 9500 core switch to a storage cluster 15 meters away across EMI-heavy electrical rooms. Single-mode’s immunity to interference ensured zero packet loss, whereas multimode would’ve required costly shielding. A common pitfall: underestimating bend radius. Even slight kinks in 20M runs can spike loss—always use slack loops. While SMF costs more upfront, its lifespan and upgrade potential justify the investment for mission-critical links. Sometimes, “short” runs need long-haul optics.