About Cisco ISR 4331 K9 Router

The Cisco ISR 4331/K9 is a high-performance enterprise router designed to deliver secure, scalable, and intelligent WAN connectivity. Part of the Cisco 4000 Series Integrated Services Routers, the ISR 4331 offers a perfect balance of performance, flexibility, and advanced security for branch offices, remote sites, and medium-sized businesses.

Powered by Ciscos multi-core architecture, the ISR 4331 separates control, data, and services processingdelivering consistent high throughput even with advanced services like VPN, firewall, IPS, WAN optimization, and application visibility. The router supports up to 100 Mbps default throughput, upgradeable to 300 Mbps with licenses, making it ideal for growing network infrastructures.

It includes multiple Gigabit Ethernet WAN/LAN ports, modular interface slots, integrated security features, and robust QoS capabilitiesensuring reliable application performance across all branch networks. With support for Cisco DNA, SD-WAN, and advanced automation tools, the ISR 4331 provides future-ready network performance with simplified management.

Key Features & Benefits

High-Performance Multi-Core Architecture

• Separates control plane & data plane

• High-speed forwarding even with security services enabled

• Scalable performance (100300 Mbps with licenses)

Advanced Security (Built-In)

• Zone-based firewall

• Secure VPN (IPsec/SSL)

• IOS XE security enhancements

• Identity-based security policies

Flexible WAN & LAN Connectivity

• 3 Gigabit Ethernet ports

• 2 NIM (Network Interface Module) slots

• 1 Service Module slot

• Support for fiber, copper, LTE (via modules)

SD-WAN Ready

• Optimized branch connectivity

• Intelligent path selection

• Centralized policy management

Modular Design

• Add-on modules for WAN, voice, security, switching

• Upgradable licenses (HSEC, Boost licenses)

Simplified Management

• Cisco DNA Center

• Cisco Prime

• CLI & WebUI

• Zero-touch provisioning

Ideal For

• Branch offices

• Retail chains

• Medium enterprises

• Secure multi-site WAN networks