Cisco ISR4431-V/K9
Cisco ISR 4431 UC Bundle, PVDM4-64, UC
Product Highlights
What's Included
4GB DRAM Control/Services Plane (2x MEM-4400-2G)
8GB Flash (1x MEM-FLSH-8G)
(1) PWR-4430-AC
(1) AC Power Cord
(1) Rackmount Kit (ACS-4430-RM-19)
(1) PVDM4-64
Branch offices and regional sites increasingly need a single platform that handles WAN routing, security, and unified communications — without the complexity and cost of managing separate appliances. The Cisco ISR4431-V/K9 is the UC (Unified Communications) bundle of the Cisco ISR 4431 Integrated Services Router, purpose-built to deliver converged voice, video, and data services at the WAN edge.
Powered by Cisco IOS XE on a multi-core architecture with physically separated control and data planes, the ISR 4431 delivers 500 Mbps to 1 Gbps of aggregate throughput and supports pay-as-you-grow performance licensing. The included PVDM4-64 digital signal processing module provides 64 channels of voice/video processing, enabling IP telephony, conferencing, transcoding, and voice gateway functionality right out of the box. The bundled UC License activates Cisco Unified Communications Manager Express (CME) and Survivable Remote Site Telephony (SRST), ensuring branch-level call control and WAN-outage survivability.
With 4 onboard Gigabit Ethernet RJ-45 ports and 4 SFP ports, plus 3 NIM slots and 1 ISC slot for modular expansion, the ISR4431-V/K9 adapts to diverse connectivity requirements — from MPLS and Internet WAN links to T1/E1 voice trunks. Dual power supply support, a compact 1RU form factor, and Cisco SD-WAN compatibility make this router an ideal foundation for secure, voice-enabled enterprise branches.
Features & Benefits
Unified Communications Ready
The ISR4431-V/K9 ships with a PVDM4-64 DSP module and UC License, enabling Cisco Unified CME, SRST, SIP/H.323/MGCP voice gateway services, and hardware-based transcoding and conferencing. Deploy a full branch PBX or voice gateway without purchasing additional voice hardware or licenses.
Scalable WAN Performance
The ISR 4431 delivers 500 Mbps default aggregate throughput, upgradeable to 1 Gbps with the FL-44-PERF-K9 performance license. A Boost license unlocks over 4 Gbps of CEF-only throughput. This pay-as-you-grow model protects your investment as bandwidth demands increase.
Multi-Core Distributed Architecture
The Cisco 4431 uses a quad-core Intel processor with physically separated control, data, and services planes. Each plane has dedicated CPU cores and memory, ensuring that voice processing, security inspection, and packet forwarding never compete for the same resources.
Modular Expansion
Three NIM slots and one ISC slot support a wide range of interface modules — including T1/E1 voice NIMs, additional Ethernet NIMs, serial WAN NIMs, and service modules. Online Insertion and Removal (OIR) lets you swap modules without disrupting router operation.
High Availability & Redundancy
The chassis supports dual internal power supplies (AC, DC, or PoE options) for power redundancy. Combined with SRST for voice survivability and Cisco IOS XE's robust failover capabilities, the ISR 4431 keeps mission-critical services running even during component or WAN failures.
Security & SD-WAN Integration
Cisco IOS XE provides integrated IPsec and SSL VPN, zone-based firewall, and advanced threat defense capabilities. The ISR 4431 is fully compatible with Cisco SD-WAN, enabling centralized policy management, application-aware routing, and secure cloud connectivity across distributed branches.
Deployment Scenarios
Enterprise Branch Office with Unified Communications
Deploy the ISR4431-V/K9 as a converged WAN router and voice gateway at medium to large branch offices. The included PVDM4-64 and UC License enable local call control via CME, PSTN connectivity through SIP trunks or T1/E1 NIMs, and WAN-outage survivability with SRST — all on a single 1RU platform.
Regional Aggregation Site
Use the ISR 4431's 500 Mbps–1 Gbps throughput and 8 onboard GE ports (4 RJ-45 + 4 SFP) to aggregate traffic from multiple smaller branch sites over MPLS or Internet VPN links. The 3 NIM slots allow you to add WAN interfaces as the number of connected sites grows.
SIP Trunk Voice Gateway
Leverage the PVDM4-64 DSP module for hardware-based transcoding and conferencing to bridge legacy PBX systems with SIP-based service providers. The 64-channel DSP capacity handles substantial call volumes, making this bundle ideal for organizations transitioning to IP telephony.
Cisco SD-WAN Edge Deployment
Deploy the ISR 4431 as an SD-WAN edge device running Cisco IOS XE SD-WAN. Centralized orchestration through vManage simplifies policy deployment, while application-aware routing optimizes traffic across hybrid WAN links — with voice services running locally on the same platform.
General
Performance
Interfaces
Expansion
Memory & Storage (As Shipped)
Voice / DSP
Power
Physical
Environmental
Compliance
Compatibility Notes
Platform Compatibility:
- Runs Cisco IOS XE software; compatible with Cisco SD-WAN (vManage/vSmart/vBond) deployments
- Supports NIM (Network Interface Modules) for T1/E1, Ethernet, serial, and other interfaces
- ISC slot supports PVDM4-series DSP modules (PVDM4-64 pre-installed in this bundle)
- Compatible with SFP modules (GLC-SX-MMD, GLC-LH-SMD, GLC-T, etc.) in the 4 onboard SFP ports
Memory (as shipped in this bundle):
- 2 GB DRAM Data Plane (MEM-4400-DP-2G) — maximum 2 GB
- 4 GB DRAM Control/Services Plane (2x MEM-4400-2G) — upgradeable to 16 GB maximum
- 8 GB Flash (MEM-FLSH-8G) — upgradeable to 32 GB maximum
Power:
- Ships with 1x PWR-4430-AC power supply; supports optional second AC, DC, or PoE power supply (PWR-4430-POE-AC) for redundancy
Downloads & Resources
Frequently Asked Questions
| Part Number | Product | Key Difference |
|---|---|---|
| ISR4431/K9 | Cisco ISR 4431 (Base) | Base router without PVDM4-64 DSP module or UC License — choose if voice services are not required |
| ISR4431-SEC/K9 | Cisco ISR 4431 Security Bundle | Includes Security license instead of UC license — ideal for security-focused deployments without voice needs |
| ISR4431-VSEC/K9 | Cisco ISR 4431 Voice + Security Bundle | Combines UC and Security licenses with PVDM4-64 and CUBE-25 — for deployments needing both voice and advanced security |
| ISR4331-V/K9 | Cisco ISR 4331 UC Bundle | Lower-tier UC bundle with 100–300 Mbps throughput and PVDM4-32 — suited for smaller branch offices with fewer voice channels |