Cisco 4331 Integrated Services Router (ISR4331/K9)

The Cisco 4331 Integrated Services Router (ISR4331/K9) is a high-performance, modular enterprise router designed for medium-sized branch offices that require secure, scalable, and application-aware networking. Built on a multicore CPU architecture that separates control, data, and services planes, this router ensures consistent performance even under heavy workloads. With support for SD-WAN, advanced security features, and flexible expansion options, the ISR4331/K9 provides a reliable foundation for modern enterprise edge deployments.

Product Features

Modular and Scalable Design

Equipped with multiple expansion slots including 2 NIM slots, 1 SM-X slot, and 1 ISC slot, allowing flexible integration of WAN, LAN, voice, and compute modules.

High-Performance Throughput

Supports software-defined throughput starting at 100 Mbps, upgradeable to 300 Mbps with a performance license, and exceeding 2 Gbps with boost licensing.

Advanced Security Integration

Includes built-in firewall capabilities, hardware-accelerated VPN support, Cisco Trust Anchor technologies, and secure boot for enhanced protection against cyber threats.

SD-WAN Capability

Fully compatible with Cisco SD-WAN solutions, enabling intelligent traffic routing across MPLS, broadband, and cloud connections.

Unified Communications Support

Voice- and video-ready architecture with support for PVDM4 modules and UCS E-Series for edge compute and collaboration services.

Flexible Power Options

Supports internal AC power supply and optional PoE power with up to 530W platform capacity for connected devices.

Reliable Multicore Architecture

Separates control, services, and data planes to maintain performance and stability during high traffic and service loads.

Product Specifications

• Throughput: 100 Mbps default; 300 Mbps with performance license; over 2 Gbps with boost license
• IPsec Throughput: Up to 300 Mbps with hardware acceleration
• Ethernet Ports: 3 x Gigabit Ethernet (1 combo RJ-45/SFP, 1 RJ-45, 1 SFP)
• Management Ports: 1 x RJ-45 console, 1 x mini-USB console, 1 x RJ-45 auxiliary
• Expansion Slots:2 x NIM (Network Interface Module) slots, 1 x SM-X (Enhanced Service Module) slot, 1 x ISC slot for PVDM4 modules
• Memory: 4 GB DRAM (expandable to 16 GB), 4 GB Flash (expandable to 16 GB)
• Form Factor: 1RU rack-mountable
• Dimensions: 44.45 x 438.15 x 438.15 mm
• Power Supply: Internal AC (100 to 240 VAC); optional PoE power supply up to 530W
• PoE Capability: Up to 250W available for endpoints with PoE PSU
• Operating Temperature: 0°C to 40°C (32°F to 104°F)
• SD-WAN Support: Yes
• Security Features: Firewall, VPN, Trust Anchor, secure boot
• Voice Support: Compatible with PVDM4 DSP modules
• Flash and DRAM Upgrades: Up to 16 GB each
• Common Power Supply Options: PWR-4330-AC, PWR-4330-POE-AC
• Voice DSP Options: PVDM4-32, PVDM4-64, PVDM4-128