Cisco CISCO2901/K9
Cisco 2901 w/2 GE,4 EHWIC,2 DSP
Product Highlights
What's Included
256MB Flash (1x MEM-CF-256MB)
(1) PWR-2901-AC
(1) AC Power Cord
(1) Rackmount Kit (ACS-2901-RM-19)
Branch offices and small sites need a router that does more than just forward packets — they need a platform that consolidates routing, security, voice, and WAN optimization into a single managed device. The CISCO2901/K9 is the Cisco 2901 Integrated Services Router (ISR G2), purpose-built to deliver exactly that.
With 2 integrated Gigabit Ethernet ports, 4 Enhanced High-Speed WAN Interface Card (EHWIC) slots, and 2 PVDM slots for digital signal processing, the Cisco 2901 provides a modular foundation that scales with your business. Embedded hardware-based encryption acceleration handles IPSec VPN workloads without burdening the route processor, while Cisco IOS IP Base supports enterprise routing protocols including OSPF, EIGRP, BGP, and MPLS.
This unit ships with 512 MB DRAM, 256 MB CompactFlash, an AC power supply (PWR-2901-AC), AC power cord, and a 19-inch rackmount kit (ACS-2901-RM-19) — everything needed for a standard rack deployment. The Cisco 2901 is part of the Cisco 2900 Series ISR G2 family, which integrates market-leading security, unified communications, and wireless services into a compact 1RU form factor. Whether you're deploying a secure WAN edge, a small-office voice gateway, or a managed-services CPE device, the CISCO2901/K9 delivers enterprise-grade capabilities at a branch-office price point.
Features & Benefits
Modular Expansion & Future-Proofing
The Cisco 2901 features 4 EHWIC slots, 2 PVDM slots, and 1 Internal Services Module (ISM) slot, allowing you to add WAN interfaces (T1/E1, xDSL, fiber), EtherSwitch modules, wireless controllers, or voice DSPs as requirements change. This modular architecture protects your investment by letting you expand capabilities without replacing the chassis.
Integrated Security & VPN
Onboard hardware encryption acceleration delivers high-throughput IPSec VPN performance with minimal CPU overhead. The platform supports Cisco IOS Zone-Based Firewall, VPN (including DMVPN), and optional intrusion prevention — consolidating multiple security functions into a single device and reducing the need for standalone security appliances at the branch.
Voice & Unified Communications Ready
With 2 onboard PVDM slots, the Cisco 2901 can host Cisco Unified Communications Manager Express (CME), Survivable Remote Site Telephony (SRST), or Cisco Unity Express for voicemail. Add optional DSP modules to enable analog/digital voice gateways and support IP telephony at remote sites without a dedicated call server.
Enterprise Routing Protocols
Cisco IOS IP Base provides a comprehensive routing feature set including OSPF, EIGRP, BGP, IS-IS, MPLS, PBR, and GRE tunneling. Advanced QoS features like CBWFQ and WRED ensure that latency-sensitive traffic such as voice and video receives priority treatment across your WAN links.
Energy Efficiency & Compact Design
At just 1RU and approximately 40W typical power consumption, the Cisco 2901 is designed for space- and power-constrained branch deployments. Cisco EnergyWise technology provides visibility and control over device power usage, helping organizations meet sustainability goals while reducing operating costs.
Deployment Scenarios
Branch Office WAN Edge Router
Deploy the CISCO2901/K9 as the primary WAN edge device at branch locations. With dual GE ports, VPN acceleration, and support for EIGRP/OSPF/BGP, it provides secure, reliable connectivity back to headquarters or data centers over MPLS, broadband, or dedicated WAN circuits.
Small Office Voice Gateway
Equip the Cisco 2901 with PVDM3 modules and EHWIC voice interface cards to serve as an integrated voice gateway. Run CME or SRST to provide local call processing and survivability, eliminating the need for a separate PBX at small sites.
Managed Services CPE
Service providers can deploy the Cisco 2901 as customer-premises equipment for managed WAN, security, and voice services. Its modular design and broad IOS feature set simplify multi-tenant management while the compact 1RU form factor fits easily into customer environments.
Lab & Certification Training
The Cisco 2901 ISR G2 is widely used in CCNA, CCNP, and CCIE lab environments. Its support for a full range of enterprise routing protocols, VPN, and QoS features makes it an ideal hands-on training platform for networking professionals.
General
Interfaces & Expansion
Memory
Performance
Protocols & Features
Power
Physical
Environmental
Compliance
Compatibility Notes
Platform Family: Cisco 2900 Series Integrated Services Routers (ISR G2)
Compatible EHWIC Modules (examples): EHWIC-1GE-SFP-CU, EHWIC-D-8ESG, EHWIC-VA-DSL-A, HWIC-4ESW, HWIC-2T, HWIC-1DSU-T1
Compatible PVDM Modules: PVDM3-16, PVDM3-32, PVDM3-64
Compatible ISM Modules: ISM-SRE-300-K9
Power Supply: Ships with PWR-2901-AC (AC). Optional PWR-2901-POE (PoE) available separately.
Memory: Ships with 512 MB DRAM (MEM-2900-512MB) and 256 MB CompactFlash (MEM-CF-256MB). DRAM expandable up to 2 GB. CompactFlash expandable up to 4 GB per slot.
End-of-Sale Notice: Cisco announced End-of-Sale for the Cisco 2900 Series on November 17, 2016, with last order date of December 9, 2017. The recommended migration path is the Cisco 4000 Series ISR (e.g., ISR4321/K9). This product remains fully functional and is available on the secondary market.
Downloads & Resources
Frequently Asked Questions
| Part Number | Product | Key Difference |
|---|---|---|
| CISCO2911/K9 | Cisco 2911 ISR | Adds a 3rd GE port (1 SFP-based), 3 EHWIC slots, 3 PVDM slots, and a service module slot for higher-density deployments. |
| CISCO2921/K9 | Cisco 2921 ISR | Higher performance with 3 GE ports, 4 EHWIC slots, 3 PVDM slots, and a double-wide service module slot for larger branch offices. |
| ISR4321/K9 | Cisco ISR 4321 | Cisco's recommended replacement for the 2901; ISR 4000 Series with higher throughput, IOS XE, and active Cisco support. |
| CISCO1941/K9 | Cisco 1941 ISR | Lower-cost ISR G2 with 2 GE ports and 2 EHWIC slots — suitable for smaller sites with fewer expansion needs. |
