ISR4321-V/K9 Cisco ISR 4321 UC Bundle, UC License

Cisco ISR4321-V/K9 - Overview

The ISR 4321 is part of the Cisco 4000 Series Integrated Services Routers, designed for small to medium branch deployments. The V bundle adds voice and collaboration capabilities, allowing the router to act as a branch PBX, voice gateway, or unified communications platform.

🔧 Key Hardware Specs

• Form Factor: 1RU rack-mountable router
• Performance:
  • 50 Mbps default throughput, software-upgradeable to 100 Mbps
• Interfaces:
  • 1x RJ45/SFP combo Gigabit Ethernet WAN/LAN ports
  • 1x RJ45 Gigabit Ethernet LAN port
  • 2x NIM (Network Interface Module) slots
  • 1x ISC (Internal Services Card) slot
    
• Memory/Storage:
  • 4 GB DRAM (upgradeable to 8 GB)
  • 4 GB flash (upgradeable to 8 GB)
• Software: Runs Cisco IOS XE

V Bundle Features

The V license package enables:

• Cisco Unified Communications Manager Express (CME) - embedded call control for branch PBX functionality
• Cisco Survivable Remote Site Telephony (SRST) - ensures voice continuity if WAN connectivity to HQ is lost
• Voice Gateway Services - SIP, H.323, MGCP, and analog/digital voice interface support (via NIM modules)
• Integrated Conferencing and Messaging - branch-level collaboration services
• Secure Voice - encryption and secure signaling for compliance
  

🧩 Ideal Use Cases

• Branch offices needing local call control and survivability
• Enterprises deploying hybrid UC solutions with centralized and branch-level voice services
• Retail or distributed sites requiring integrated voice/video alongside WAN routing
• Organizations migrating from ISR G2 voice bundles (e.g., 2900/3900 series with UC licenses)