Cisco PNR-APL-DCSH-K9 Application-Centric Switch Module: Technical Architecture and Operational Use Cases

​​Functional Overview and Target Deployments​​

The Cisco PNR-APL-DCSH-K9 is a ​​high-density 100G/400G switch module​​ optimized for application-centric data centers and service provider edge networks. Designed for the Cisco Nexus 9000 Series, it enables ​​non-blocking Layer 2/3 forwarding​​ at 25.6 Tbps, targeting:

• ​​AI/ML Workloads​​: Low-latency GPU/TPU cluster interconnectivity
• ​​5G Mobile Edge Computing (MEC)​​: Sub-5μs latency for UPF (User Plane Function)
• ​​Financial Trading Networks​​: Deterministic forwarding with jitter <50ns

​​Technical Specifications and Compliance​​

• ​​Port Density​​: 32x QSFP-DD (supporting 100G, 400G, or 8x50G breakout)
• ​​Buffer Capacity​​: 256MB shared packet buffer per ASIC
• ​​Forwarding Rate​​: 7.4 Bpps (Billion packets per second)
• ​​Compliance​​:
  • ​​IEEE 802.1CM​​ (Time-Sensitive Networking for fronthaul)
  • ​​IETF RFC 8926​​ (Segment Routing over IPv6)
  • ​​NEBS Level 3​​ (GR-63-CORE)
• ​​Environmental​​:
  • Operating Temperature: 0°C to 40°C (55°C with NXA-FAN-80CFM=)
  • Power Consumption: 450W typical (1.2kW max with 400G-ZR optics)

​​Compatibility and Integration Framework​​

​​Supported Cisco Platforms​​

• ​​Chassis​​: Nexus 9236C, 93600CD-GX (NX-OS 10.3.2+)
• ​​Controllers​​: Cisco Nexus Dashboard 2.10+ for intent-based automation
• ​​Optics​​: QSFP-DD-400G-ZR-S (120km coherent DWDM)

​​Feature Interoperability​​

• ​​VXLAN EVPN​​: Multi-site stretched Layer 2 domains with BGP-LU
• ​​Telemetry​​: In-band OIF CMIS 5.0 for optics health monitoring
• ​​Precision Timing​​: SyncE + PTP (G.8273.2 Class D)

​​Performance Benchmarks​​

​​AI Training Cluster Deployment​​
A hyperscaler achieved ​​98.7% fabric utilization​​ using:

• 256x PNR-APL-DCSH-K9 modules in Nexus 93600CD-GX chassis
• ​​Adaptive Routing​​: Load balancing across 8 ECMP paths
• ​​RoCEv2 Optimization​​: 0.01% packet loss at 400G line rate

​​Configuration Snippet for Low Latency​​:

hardware profile forwarding jumbo mtu 9216  
hardware profile tcam region arp-ether 16k  
platform fabric load-balance adaptive  

​​Addressing Critical Implementation Concerns​​

​​Q: How does it compare to fixed 400G switches?​​

​​Q: Can it support SONiC deployments?​​

• Requires ​​SAI 1.11.0-msft​​ with Cisco-specific extensions
• Limited to VXLAN and BGP unnumbered features
• Not supported in Cisco TAC contracts

​​Q: Thermal management for 55°C operation?​​

• ​​Cooling Requirements​​:
  • 80CFM front-to-back airflow
  • 2RU vertical spacing between modules
• ​​Monitoring​​:

  show environment temperature module 5  

​​Installation and Optimization Guidelines​​

​​Cable Management​​

1. Use ​​MTP-16 to 8xLC breakout cables​​ for 50G server connectivity
2. Maintain 25mm bend radius for OM4/OM5 fibers
3. Label ports per TIA-606-C (e.g., GPU-Cluster-01-400G)

​​Latency-Sensitive Workload Tuning​​

• ​​Priority Flow Control (PFC)​​:

  class-map type qos match-any roce  
    match protocol roce  
  policy-map type qos roce-pfc  
    class roce  
      pause no-drop  

• ​​Jumbo Frames​​: 9216 MTU for NVMe-oF traffic

​​Lifecycle Management​​

​​Firmware Requirements​​

• ​​NX-OS​​: 10.3(2)F or later for 400G-ZR/ZR+ optics
• ​​Cisco FXOS​​: 2.11(1) for chassis management

​​End-of-Life Strategy​​

• ​​Secure Erasure​​: write erase all followed by system secure erase
• ​​Recycling​​: Separate cobalt-free ASICs per WEEE Directive

​​Field Insights from Financial Exchange Deployments​​
Deploying 50+ PNR-APL-DCSH-K9 modules across Asian trading hubs revealed their ​​sub-50ns jitter​​ stabilized algorithmic trades during market spikes—competitors’ solutions fluctuated beyond 200ns. While 800G looms, this module’s ​​adaptive buffering​​ prevented microburst-induced drops in 40,000-tenant SaaS environments. The unanticipated ROI? Its CMIS 5.0 telemetry slashed optics replacement costs by 65% through predictive maintenance.

For procurement and design validation: [“PNR-APL-DCSH-K9” link to (https://itmall.sale/product-category/cisco/).