2921/K9 Modular Router with Gigabit Ethernet and Advanced Security Services
Product Overview
The Cisco ISR 2921 (model CISCO2921/K9) is a modular 2U integrated services router designed for small to medium-sized enterprise branch deployments. It supports secure data, voice, and video services with embedded encryption acceleration, modular expansion slots, and Gigabit Ethernet connectivity.
Product Details and Features
| Item | Description |
| Model | CISCO2921/K9 |
| Product Type | Integrated Services Router (ISR) |
| Enclosure | 2RU rack-mountable chassis |
| Integrated Ethernet | 3 × 10/100/1000BASE-T RJ-45 ports (one port optionally replaceable by SFP) |
| Expansion Slots | 4 × Enhanced High-Speed WAN Interface Card (EHWIC) slots; 2 service module slots; onboard DSP slots |
| RAM | 512 MB installed (upgradable to 2 GB) |
| Flash Memory | 256 MB installed (upgradable to 8 GB) |
| Power Supply | Internal AC power supply (supports external RPS for redundancy) |
| Operating System | Cisco IOS XE with IP Base feature set |
| Security & VPN | Includes firewall, IPS, CBWFQ, NetFlow, IPv6, secure VPN options (DMVPN, SSL, Easy VPN) |
| Voice/DSP Support | Supports PVDM3 modules for voice/video processing in ISM or DSP slots |
| Routing Protocols | Static IP routing, OSPF, BGP, EIGRP, IS‑IS, MPLS, policy-based routing, IPv6 |
| Dimensions (W×D×H) | Approx. 438 × 470 × 89 mm |
| Weight | Approx. 13.2 kg |
| Operating Temperature | 0 °C to 40 °C |
| Humidity Range | 10 % to 85 % non-condensing |
| Ideal For | Secure branch services, voice‑enabled WAN, VPN aggregation, modular expansion for future growth |
Product Highlights
Three integrated Gigabit Ethernet ports, with one port optionally convertible to SFP for flexible deployment
Modular architecture with support for four EHWIC slots, service modules, and DSP for voice/video
Hardware-accelerated encryption and firewall throughput for secure branch services
Supports advanced routing, MPLS, QoS, and identity-based access control without additional licensing
Designed for enterprise branch environments with stackable DSP/voice support and future scalability
Similar Models Comparison
| Model | Integrated Ports | PoE Support | Expansion Slots | Target Deployment |
| CISCO2921/K9 | 3 × 1G (one optional SFP) | Optional via modules | 4 EHWIC + 2 service module slots | Secure branch router with voice / encryption |
| CISCO2911/K9 | Same as 2921 | Optional | 4 EHWIC + 2 service module slots | Lower throughput option in ISR 2900 series |
| CISCO2951/K9 | Same as 2921 | Optional | 4 EHWIC + 2 service slots | Higher model with greater throughput and expansion |
Latest Models in the Same Series
| Model | Ports | Expansion Support | Suitable Use Case |
| CISCO2921/K9 | 3 × Gigabit Ethernet | 4 EHWIC + DSP + service slots | Secure voice and data branch deployments |
| CISCO2951/K9 | 3 × Gigabit Ethernet | Same | Higher throughput, advanced services |
| Cisco ISR 4000 Series | Various | Enhanced performance and features | Modern upgrade path for faster routing and services |
