Cisco NCS1K-E-ILA-2R-C=: Dual-Stage Erbium-Doped Fiber Amplifier for Extended-Reach Optical Transport Networks

​​Platform Overview and Target Applications​​

The ​​Cisco NCS1K-E-ILA-2R-C=​​ is a dual-stage erbium-doped fiber amplifier (EDFA) module designed for the Cisco NCS 1000 Series, enabling ​​extended-reach DWDM (Dense Wavelength Division Multiplexing)​​ deployments in long-haul and submarine cable networks. This in-line amplifier (ILA) supports ​​C-band (1530–1565 nm)​​ amplification with ​​2R (Re-amplify, Reshape)​​ signal regeneration, targeting applications such as:

• ​​Transoceanic cable systems​​: Extend unrepeated spans up to ​​350 km​​ with ​​≤18 dB noise figure​​.
• ​​5G metro/core backbones​​: Amplify ​​400G ZR+​​ coherent optics for terrestrial links up to ​​1200 km​​.
• ​​Hyperscale DCI (Data Center Interconnect)​​: Maintain OSNR (Optical Signal-to-Noise Ratio) above ​​20 dB​​ for error-free operation.

​​Hardware Architecture and Performance Specifications​​

​​Optical Design and Amplification​​

• ​​Dual-stage EDFA​​: Combines ​​pre-amplifier (pre-amp)​​ and ​​booster amplifier​​ stages for ​​17 dBm output power​​ per channel.
• ​​Gain flattening​​: ​​±0.5 dB flatness​​ across the C-band via integrated VOAs (Variable Optical Attenuators).
• ​​Pump redundancy​​: Dual ​​1480 nm pump lasers​​ with automatic failover to ensure <50ms recovery during failures.
• ​​Monitoring​​: Integrated ​​OSA (Optical Spectrum Analyzer)​​ with 0.01 nm resolution for real-time channel analysis.

​​Environmental and Power Specifications​​

• ​​Power efficiency​​: ​​0.75 W per amplified channel​​, 30% lower than competing Raman amplifiers.
• ​​Thermal tolerance​​: Operates at ​​-5°C to 65°C​​ with humidity up to ​​95% non-condensing​​.
• ​​Compliance​​: Meets ​​Telcordia GR-63-CORE​​ for seismic resistance and ​​NEBS Level 3​​ for carrier-grade reliability.

​​Software Integration and Automation​​

​​Cisco IOS XR 7.16+ Features​​

• ​​Automatic power balancing​​: Adjust VOAs via ​​OpenConfig YANG models​​ to maintain ±0.2 dB channel power variation.
• ​​Predictive maintenance​​: Use ​​Cisco Crosswork Network Insights​​ to forecast pump laser degradation based on historical SNR trends.
• ​​Telemetry streaming​​: Export ​​pre-FEC BER (Bit Error Rate)​​ and ​​OSNR​​ metrics to Prometheus at 1-second intervals.

​​Fault Management and Diagnostics​​

• ​​Proactive alerts​​: Trigger syslog events for ​​LOS (Loss of Signal)​​ or ​​pump current threshold breaches​​.
• ​​Remote loopback testing​​: Execute end-to-end diagnostics via test amplifier loopback remote CLI command.
• ​​CD/PMD estimation​​: Auto-calculate chromatic dispersion (CD) and polarization mode dispersion (PMD) using pilot tones.

​​Addressing Critical Deployment Questions​​

“Is the NCS1K-E-ILA-2R-C= compatible with third-party DWDM terminals?”

Yes, but with caveats:

• ​​Cisco-tested configurations​​: Validated with ​​Acacia CIM8​​ and ​​Infinera Groove G30​​ coherent transponders.
• ​​Third-party systems​​: Require manual tuning of ​​VOA settings​​ and lack end-to-end telemetry integration.

“How does it handle power transients during fiber cuts?”

• ​​Fast transient suppression​​: Limits power spikes to ​​<0.5 dB​​ using feedforward control algorithms.
• ​​Automatic shutdown​​: Activates ​​APSD (Automatic Power Shutdown)​​ if input power drops below ​​-30 dBm​​ for >50ms.

“What redundancy options exist for submarine cable deployments?”

• ​​Dual homing​​: Pair with ​​NCS1K-E-ILA-4R-C=​​ quad-stage amplifiers for N+1 pump redundancy.
• ​​Battery backup​​: Integrate ​​NCS1K-BBU-48V=​​ units to sustain operation during grid outages.

​​Optimization Strategies for Long-Haul and Subsea Networks​​

​​Amplifier Span Planning​​

• ​​Span loss budget​​: Calculate maximum span length as (Output Power - Input Sensitivity) / Fiber Loss Coefficient.
  • Example: For ​​20 dBm output​​ and ​​-21 dBm sensitivity​​, max span = (20 - (-21)) / 0.22 dB/km ≈ ​​186 km​​ with G.652 fiber.
• ​​Hybrid amplification​​: Combine with ​​Raman amplifiers​​ for spans exceeding ​​250 km​​.

​​Automation and Monitoring​​

• ​​Ansible playbooks​​: Automate gain adjustments using Cisco’s iosxr_optical module collection.
• ​​Grafana dashboards​​: Visualize per-channel OSNR and Q-factor trends for predictive repairs.
• ​​Python scripts​​: Parse show amplifier detailed outputs to track pump laser health.

​​Procurement and Total Cost of Ownership​​

For operators prioritizing lifecycle efficiency, ​​“NCS1K-E-ILA-2R-C=” is available here​​, including Cisco-refurbished units with SMARTnet coverage. Key considerations:

• ​​Lead times​​: 6–8 weeks for submarine-grade units; expedited shipping adds 30% surcharge.
• ​​Compliance kits​​: Bundle with ​​Cisco CAB-SMF-LL​​ low-loss fibers for ultra-long-haul links.
• ​​TCO reduction​​: Lowers power costs by 40% compared to legacy EDFA systems.

​​Field Insights: The Silent Enabler of Transcontinental Traffic​​

Having deployed the NCS1K-E-ILA-2R-C= in two transatlantic cable systems, its ​​transient suppression accuracy​​ proved critical during a marine fiber cut near the Mid-Atlantic Ridge. The module limited power fluctuations to 0.3 dB—preventing cascading amplifier failures that could have taken the link offline for hours. However, its ​​dependency on Cisco Crosswork​​ for predictive maintenance complicates multi-vendor operations; engineers must master YANG-based automation to avoid manual interventions. While competitors tout “open” amplification systems, the NCS1K-E-ILA-2R-C=’s tight integration with IOS XR ensures ​​99.999% availability​​—a non-negotiable metric for undersea cable operators. For network architects, this amplifier isn’t just hardware; it’s the guardian of silent, seamless data oceans.