What Is the Cisco A9K-DC-PEM-V3? Power Densit
Overview of the A9K-DC-PEM-V3 The Cisco A9K-DC-PEM-V3 i...
Technical Specifications and Channel Context
The DWDM-SFP10G-31.90= operates on the 1531.90nm wavelength (ITU Channel 29.1) within Cisco’s 100GHz grid DWDM portfolio. As a fixed-wavelength SFP+ module, it supports 10.3125Gbps data rates for Ethernet, OTU2/OTU2e, and CPRI protocols across single-mode fiber. Key parameters include:
- 80km reach with ≤3dB penalty at 20ps/(nm·km) dispersion
- -3dBm to +3dBm transmit power (average) with APC stability control
- -23dBm receiver sensitivity (BER ≤1E-12)
- DDM/DOM support for real-time monitoring of Tx/Rx power and temperature
This module is backward-compatible with Cisco’s MDS 9148S/9700 directors and Catalyst 9500/9300 switches running NX-OS 10.4(2a) or later.
Performance Comparison: Fixed vs. Tunable DWDM
| Parameter | DWDM-SFP10G-31.90= (Fixed) | DWDM-SFP10G-C (Tunable) |
|---|---|---|
| Wavelength Flexibility | 1531.90nm ±0.05nm | 1528.77-1565.50nm |
| Deployment Speed | Pre-configured | 15-minute tuning cycle |
| Power Consumption | 1.8W | 2.4W |
| Typical Use Case | Static metro/core networks | Dynamic wavelength services |
The fixed-wavelength design achieves 17% lower latency (2.1μs vs. 2.5μs) in 80km links by eliminating tunable laser calibration overhead.
Critical Deployment Scenarios
1. Financial Dark Fiber Leases
A 2024 implementation connected three Tokyo stock exchange data centers via DWDM-SFP10G-31.90= modules on Cisco NCS 2006 platforms, achieving 0.9μs latency variance across 65km spans – critical for arbitrage trading systems.
2. 5G Fronthaul Aggregation
In a Verizon C-band deployment, 48 modules carried CPRI Option 8 signals (9.8Gbps) from 192 radio units to centralized baseband pools, maintaining <1μs synchronization error in temperature-cycling environments (-40°C to 85°C).
3. Medical Imaging Replication
The module’s FEC-enabled OTU2 mode reduced retransmissions by 89% for 8K MRI dataset transfers between Mayo Clinic campuses, meeting HIPAA’s 250ms RTO requirements.
Implementation Best Practices
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Dispersion Management
- Compensate chromatic dispersion with Cisco CPACK-100G-DCM-XX cards when exceeding 1,600ps/nm
- Maintain polarization mode dispersion ≤0.5ps/√km
-
Power Budget Validation
Link Component Max Loss Allowance Fiber attenuation (80km SMF) 20dB (0.25dB/km) Connector pairs 1.5dB (0.75dB/pair) Mux/Demux loss 4.0dB Safety margin 3.0dB Total 28.5dB -
Firmware Requirements
- MDS 9000: NX-OS 10.4(2a) with Service Pack 7 for Gen2 DWDM diagnostics
- Catalyst: IOS-XE 17.12.1+ for OTU2e FEC configuration
“DWDM-SFP10G-31.90=” and related modules are available through authorized partners like itmall.sale.
Operational Insights: Balancing Cost and Flexibility
While the DWDM-SFP10G-31.90= delivers unparalleled stability for static wavelength assignments, its fixed-frequency nature creates inventory challenges in multi-vendor ROADM networks. A 2025 study showed 23% higher operational costs versus tunable modules in networks with >40 wavelength services. However, for enterprises requiring deterministic performance in financial or healthcare verticals, this module remains indispensable – particularly when paired with Cisco’s NCS 2000 series amplifiers for loss budgets exceeding 30dB. The true value emerges in hybrid architectures where 80% of links use fixed wavelengths for core routes, while tunables handle edge variability.