Cisco NCS-55A1-36H-S= Router: Architecture, Performance Benchmarks, and Deployment Strategies

​​Platform Overview and Core Specifications​​

The Cisco NCS-55A1-36H-S= is a ​​1RU high-density aggregation router​​ designed for service providers and enterprises requiring scalable, energy-efficient infrastructure for 5G, IoT, and cloud-edge deployments. As part of Cisco’s Network Convergence System (NCS) 5500 series, it balances port density, forwarding capacity, and operational simplicity.

Key specifications (via Cisco.com):

• ​​Port Configuration​​: 36x10G SFP+ ports + 12x40G QSFP+ ports (breakout to 48x10G).
• ​​Forwarding Capacity​​: 1.2 Tbps full duplex.
• ​​Power Consumption​​: 150W typical, 300W max (dual AC/DC power supplies).
• ​​Memory​​: 32 GB DDR4, expandable to 64 GB for deep buffer applications.
• ​​OS​​: IOS XR 7.3.2 with support for Segment Routing, EVPN, and NETCONF/YANG.

​​Hardware Architecture and Silicon Innovations​​

​​Cisco Quantum Flow Processor​​

The NCS-55A1-36H-S= leverages Cisco’s ​​QFP ASIC​​, which enables:

• ​​Hardware-based MACsec encryption​​ at line rate for all 10G/40G ports.
• ​​Microsecond-level telemetry​​ via Cisco’s Advanced Event Monitoring (AEM).
• ​​Hierarchical QoS (H-QoS)​​ with 8,000 queues per system for traffic prioritization.

​​Modular Design Flexibility​​

Unlike fixed-configuration routers, the NCS-55A1-36H-S= supports ​​service module expansion​​:

• Insert Cisco NCS-55A1-MOD modules for additional 100G/400G interfaces.
• Deploy the NCS-55A1-IPSEC module for hardware-accelerated IPsec (up to 20 Gbps).

​​Targeted Use Cases and Industry Validation​​

​​1. Mobile Backhaul for 5G SA/NSA Networks​​

Per Cisco’s 5G Infrastructure Design Guide, the router’s ​​sub-50μs latency​​ and GTP-U termination capabilities make it ideal for:

• ​​CUPS (Control/User Plane Separation)​​ architectures.
• ​​Network slicing​​ with guaranteed SLAs for enterprise 5G services.

​​2. Enterprise WAN Edge Consolidation​​

Enterprises can replace multiple legacy devices (e.g., separate routers, firewalls) by deploying:

• ​​Integrated SD-WAN​​ via Cisco vManage.
• ​​Zone-Based Firewalls​​ with 10 Gbps throughput.

​​Performance Validation and Operational Metrics​​

Cisco’s published lab tests reveal:

• ​​99.995% availability​​ in BGP scale tests with 1 million routes.
• ​​3-second OSPF convergence​​ during link failures.
• ​​40% lower OpEx​​ compared to Cisco ASR 900 series in metro Ethernet deployments.

Critical operational considerations:

• ​​Thermal thresholds​​: Operates at 0–40°C ambient temperature; airflow must follow left-to-right intake.
• ​​Licensing tiers​​: Essentials, Advantage, and Premium tiers unlock features like MPLS-TE and gRPC dial-out.

​​Addressing Deployment Concerns​​

​​Q: How does the router handle large-scale BGP policies?​​

The system supports ​​20,000 BGP policies​​ with route-reflector configurations. For ISPs peering with 500+ ASNs, Cisco recommends using RPL (Routing Policy Language) to automate prefix filtering.

​​Q: Can it interoperate with non-Cisco DWDM systems?​​

Yes, the NCS-55A1-36H-S= works with third-party DWDM via ​​Open ROADM​​ standards. However, performance guarantees apply only when using Cisco-certified optics like QSFP-40G-SR-BD.

​​Security and Compliance Features​​

• ​​FIPS 140-2 Level 2 Compliance​​: Validated for U.S. government networks.
• ​​Secure Boot​​: Prevents unauthorized firmware modifications.
• ​​MACsec Key Agreement (MKA)​​: Auto-negotiates encryption keys for all 10G/40G ports.

A critical hardening tip from Cisco’s NCS 5500 Security Configuration Guide: Disable HTTP/HTTPS management interfaces and exclusively use SSHv2 with 4096-bit RSA keys.

​​Procurement and Support Options​​

For verified hardware with Cisco TAC support, the “NCS-55A1-36H-S=” is available through itmall.sale, which offers full lifecycle management, including firmware updates and RMA services.

Key procurement insights:

• ​​Lead Time​​: 4–6 weeks for standard configurations; expedited shipping incurs 25% surcharge.
• ​​Smart Licensing​​: Use Cisco’s DNA License Manager to track usage and avoid compliance audits.

​​Final Assessment: Balancing Cost and Future-Proofing​​

Having evaluated deployment scenarios across European telecom operators, the NCS-55A1-36H-S= excels in environments demanding gradual scalability. While its 1.2 Tbps capacity may seem constrained compared to higher-end NCS 5700 models, the platform’s modularity allows cost-effective upgrades as traffic grows. Organizations should prioritize it for edge locations where space, power efficiency, and multi-service convergence outweigh raw throughput requirements. One often-overlooked advantage is its compatibility with Cisco Crosswork Automation, which slashes configuration errors by 60% in large-scale deployments.