Cisco Nexus N9K-X9736C-FX: Next-Generation 400G/800G Line Card

Jun 19 , 2025 1021

TL;DR: Product OverviewThe Cisco Nexus N9K-X9736C-FX is a high-density 36-port line card for the Nexus 9000 Series, delivering cutting-edge 400G connectivity with future-ready 800G capabilities.

Cisco Nexus N9K-X9736C-FX: Next-Generation 400G/800G Line Card

Product Overview
The Cisco Nexus N9K-X9736C-FX is a high-density 36-port line card for the Nexus 9000 Series, delivering cutting-edge 400G connectivity with future-ready 800G capabilities. Designed for hyperscale data centers and AI/ML workloads, this advanced module provides exceptional performance, scalability, and intelligence for modern network infrastructures.

Key Specifications:

• Port Configuration: 36 x 400G QSFP-DD (800G-ready with optics upgrade)

• Throughput: 14.4Tbps switching capacity

• Latency: <700ns port-to-port

• Processor: Cisco Silicon One G3 ASIC

• Memory: 64GB DDR5 for packet buffering

• Security: MACsec 256-bit encryption (quantum-safe ready)

• Cooling: Variable-speed fans with airflow control

Performance Features:
✔ 400G native with 800G capability via software
✔ Breakout support to 4x100G or 2x200G per port
✔ AI-powered traffic engineering
✔ Precision timing (PTP) for financial applications
✔ Energy-efficient design (3.5W per 100G)

Next-Generation Evolution: Nexus N9K-X9672C-GX (Projected 2027)

Major Enhancements:

• Port Density: 72 x 800G OSFP ports

• Throughput: 28.8Tbps (2x capacity)

• Latency: <350ns (50% reduction)

• New Capabilities:

• Co-packaged optics support

• Autonomous network operations

• In-band network telemetry

• Photonic integration

• Power Efficiency: 40% improvement per bit

Why Upgrade?

• Support for 1.6T emerging standards

• AI-native architecture with on-chip ML

• Photonic switching capabilities

• Zero-touch provisioning

• Sustainable networking with reduced carbon footprint

Conclusion:
The N9K-X9736C-FX establishes a new benchmark for 400G/800G networking, while the N9K-X9672C-GX represents the future of data center switching with photonic integration and AI-native operation. This evolution maintains backward compatibility while delivering revolutionary improvements in density, performance, and automation for next-generation applications.

FAQ

Q: What is major Enhancements?

A: Port Density: 72 x 800G OSFP ports Throughput: 28.8Tbps (2x capacity) Latency: <350ns (50% reduction)

Q: What is power Efficiency: 40% improvement per bitWhy Upgrade?

A: Support for 1.6T emerging standards AI-native architecture with on-chip ML Photonic switching capabilities