ISR4431/K9 with 4 GE and 3 NIM slots

Cisco ISR4431/K9 - Overview

The Cisco ISR4431/K9 is a 1RU modular router from the Cisco 4400 Series, designed for medium to large branch offices and regional aggregation sites. It provides higher throughput and scalability compared to the ISR4351, making it well-suited for enterprises that require secure, application-aware WAN connectivity. With Cisco IOS XE software, the ISR4431/K9 supports SD-WAN, advanced routing, and modular expansion for evolving branch needs.

🔧 Key Hardware Specifications

• Form Factor: 1RU rack-mountable router
• Performance:
  • 500 Mbps default throughput
  • Upgradeable to 1 Gbps or 2 Gbps with performance licenses
• Interfaces:
  • 4x RJ45/SFP combo Gigabit Ethernet WAN/LAN ports
  • 3x NIM (Network Interface Module) slots
  • 1x ISC (Internal Services Card) slot
• Memory/Storage:
  • 4 GB DRAM (upgradeable to 16 GB)
  • 4 GB flash (upgradeable to 16 GB)
• Software: Runs Cisco IOS XE
• Power: Dual redundant PSU options available

🧩 Ideal Use Cases

• Enterprise WAN edge with high throughput requirements
• Branch or regional offices needing scalable routing capacity
• Hybrid WAN and SD-WAN deployments with application-aware routing
• Organizations consolidating routing and modular services into a single ISR platform