ISR4351-VSEC/K9 All-in-One VoIP and Security SD-WAN Router
Product Overview
The Cisco ISR4351-VSEC/K9 is a fully integrated voice and security
services router, part of the Cisco ISR 4000 Series, designed for
medium-sized enterprise branches. It includes both Voice (UC) and
Security (SEC) licenses, providing advanced support for VoIP,
unified communications, IPsec VPN, zone-based firewall, and
application visibility. With modular flexibility, SD-WAN readiness,
and scalable performance from 200 Mbps up to 400 Mbps, this router
offers a cost-effective all-in-one solution for converged voice,
data, and security deployments.
Product Details
| Specification | Description |
|---|---|
| Product Code | ISR4351-VSEC/K9 |
| Series | Cisco ISR 4000 Series |
| Form Factor | 1RU Rack-Mountable |
| Default Throughput | 200 Mbps (upgradable to 400 Mbps with license) |
| Processor | Cisco QuantumFlow Processor |
| System Memory (DRAM) | 4 GB (upgradable to 16 GB) |
| Flash Storage | 8 GB (upgradable to 32 GB) |
| Integrated GE Ports | 3 x 1G RJ45 + 1 x 1G SFP |
| NIM Slots | 2 |
| SM-X Slot | 1 |
| Voice DSPs | Yes (supports SRST, CME, conferencing, transcoding) |
| Voice License Included | Yes (UC package) |
| Security License Included | Yes (SEC package – IPsec, ZBFW, AVC, CPP) |
| SD-WAN Capable | Yes |
| Redundant Power Support | Yes (external RPS optional) |
| Software | Cisco IOS XE (modular, programmable OS) |
| Virtualization Support | UCS-E, KVM, Linux containers supported |
Product Features
All-in-one platform with Voice and Security capabilities included
Supports SRST, CME, DSP modules, and TDM voice gateway features
Built-in IPsec VPN, Zone-Based Firewall, and application visibility tools
Performance-on-Demand licensing scales throughput as needed (200–400 Mbps)
Full support for SD-WAN, enabling intelligent path selection and cloud on-ramp
Modular slots accommodate LTE, FXO/FXS, T1/E1, UCS-E, and switching blades
Ideal for converged branch deployments needing VoIP, secure WAN, and data services
Similar Models Comparison
| Model | Voice Support | Security License | Max Throughput | NIM Slots | SD-WAN | Ideal Use Case |
|---|---|---|---|---|---|---|
| ISR4451-VSEC/K9 | Yes | Yes | 2 Gbps | 3 | Yes | Large enterprise voice + security |
| ISR4351-VSEC/K9 | Yes | Yes | 400 Mbps | 2 | Yes | Medium secure UC branch |
| ISR4331-VSEC/K9 | Yes | Yes | 300 Mbps | 2 | Yes | Small branch voice + security |
Latest ISR 4000 Voice & Security Series
| Model | Max Throughput | Voice + Security | SD-WAN | Form Factor | Target Branch Type |
|---|---|---|---|---|---|
| ISR4451-VSEC/K9 | 2 Gbps | Yes | Yes | 2RU | Large UC + secure branches |
| ISR4351-VSEC/K9 | 400 Mbps | Yes | Yes | 1RU | Mid-size voice + security |
| ISR4331-VSEC/K9 | 300 Mbps | Yes | Yes | 1RU | Compact secure UC branches |
