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CISCO ISR4331/K9 4000 Integrated Service Router

$100.30 (Ex. GST)

In stock: 8

The Cisco ISR4331/K9 is a 1U rack-mountable, modular Integrated Services Router from the Cisco ISR 4000 Series (launched 2013–2014). It is a mid-range branch router designed for medium-sized businesses, branch offices, and distributed enterprise WAN edge deployments requiring advanced routing, security, SD-WAN, voice, and application optimization in a compact, high-performance platform.

The ISR4331/K9 is a 3-port Gigabit Ethernet router with modular expansion capabilities. It combines routing, security, voice, and application services into a single 1U chassis. Key features include:

  • 3 onboard Gigabit Ethernet RJ-45 ports (GigabitEthernet0/0/0, 0/0/1, 0/0/2) — configurable as LAN or WAN interfaces
  • 2 NIM slots (Network Interface Modules) for expansion (e.g., T1/E1, serial, ISDN, LTE, voice, additional Ethernet)
  • 1 SM-X slot (Service Module slot) for higher-density modules (e.g., SM-X-72FXS/DID voice module, SM-X-64FXO, UCS-E server blades)
  • 1 ISM slot (Internal Service Module) for optional security/acceleration cards (e.g., ISM-VPN)
  • Dual redundant power supply bays (default single PSU; optional second for redundancy)
  • Redundant hot-swap fans (front-to-back airflow)

It runs Cisco IOS XE with modular software licensing:

  • IP Base (default) — basic routing, security, QoS
  • Upgradable to Security, UC (Unified Communications), AppX (Application Experience), or full UC license bundles

Common deployment scenarios:

  • Branch office WAN router with MPLS/Internet breakout
  • DMVPN hub/spoke or GETVPN
  • Voice gateway (SRST, CME, CUBE)
  • SD-WAN edge (with Viptela vManage/IWAN)
  • Application visibility & control (AVC, NBAR2)

The "K9" in the part number indicates the crypto-enabled version (IPsec VPN support).

Model / Part Number: ISR4331/K9

Series: Cisco 4000 Series Integrated Services Router (ISR 4331)

Form Factor: 1RU rack-mountable

Throughput: Up to 2 Gbps (aggregate routing); up to 1 Gbps encrypted (IPsec) with performance license

Onboard Ports: 3 × 10/100/1000 RJ-45

Expansion Slots: 2 × NIM + 1 × SM-X + 1 × ISM

Power Supplies: Default single 250W AC; optional dual redundant

Fans: Redundant hot-swap (front-to-back airflow)

Status (2025–2026): Legacy / End-of-Sale / End-of-Support – Cisco ended support for ISR 4000 series years ago; still widely used in branch networks

Market Availability: Refurbished or used pulls from decommissioned branch offices

Common Sources: eBay, Amazon (renewed), surplus networking resellers (Renewtech, ServerSupply, NTC-Tech)

Typical Price Range: $400–$1,200 (refurbished, depending on condition, licenses, and modules)

Processor: Multi-core CPU (Cisco QuantumFlow Processor)

DRAM: 4 GB default (expandable to 16 GB)

Flash: 8 GB default (expandable)

Onboard LAN Ports: 3 × 10/100/1000 RJ-45

Expansion Slots:
2 × NIM (e.g., NIM-2MFT-T1/E1, NIM-4G-LTE, NIM-ES2-4, NIM-1GE-CU-SFP)
1 × SM-X slot (e.g., SM-X-72FXS/DID voice module)
1 × ISM slot (e.g., ISM-VPN-3DES/3DES-AES)

Maximum Throughput: 2 Gbps (aggregate routing); 1 Gbps IPsec VPN (with boost license)

Power Consumption: ≈150–250W typical (varies with modules)

Redundant Power: Optional dual 250W AC hot-swap PSUs

Cooling: Redundant hot-swap fans (front-to-back airflow)

Management: Cisco IOS-XE CLI, web GUI (limited), Cisco Prime Infrastructure, DNA Center (limited support)

Operating Temperature: 0°C to 40°C (32°F to 104°F)

Dimensions: 1RU – 43.8 cm (W) × 43.8 cm (D) × 4.4 cm (H)

Weight: ≈8–12 kg (depending on modules)

CISCO ISR4331/K9 4000 Integrated Service Router 2nd :: Alt () Other //

CISCO ISR4331/K9 4000 Integrated Service Router 2nd :: Alt () Other //

$100.30 (Ex. GST)

$100.30 (Ex. GST)

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