C1921-3G-S-SEC/K9 Cisco ISR G2 1921 Ethernet Router

Highlights of Cisco C1921-3G-S-SEC/K9 ISR G2 Ethernet Router

The Cisco C1921-3G-S-SEC/K9 ISR G2 is a high-performance modular Ethernet router designed for secure branch connectivity and reliable enterprise networking. Built for Sprint 3G EVDO networks, it delivers strong routing capabilities, advanced security, and flexible expansion options for modern business environments.

General Information

• Manufacturer: Cisco
• Part Number: C1921-3G-S-SEC/K9
• Product Type: Ethernet Router
• Sub Type: 1921 Ethernet Router

Technical Specifications

Target Network Compatibility

• Optimized for Sprint 3G (EVDO) wireless WAN connectivity
• Integrated EHWIC module support for cellular networking
• Reliable performance for remote branch communication

Hardware Configuration

• 512 MB DRAM (maximum supported capacity)
• 256 MB internal flash memory for system storage
• Designed for stable and efficient routing performance

Network Interfaces & Expansion

• 2 x integrated 10/100/1000 Gigabit Ethernet ports
• 2 x Enhanced High-Speed WAN Interface Card (EHWIC) slots
• Flexible modular design for additional WAN services

Form Factor & Physical Design

• Compact 1U rack-mountable chassis
• Also suitable for desktop installation
• Space-saving design for enterprise branch offices

Security Capabilities

• Permanent Security (SEC) license included
• Advanced firewall protection for network safety
• Supports IPsec, SSL VPN, and encrypted tunneling
• Hardware-based encryption acceleration

Routing & Protocol Support

• Supports OSPF, EIGRP, BGP, and IS-IS protocols
• IPv4 and IPv6 static routing compatibility
• Optimized for enterprise-grade traffic management

Performance & Transfer Capabilities

• Maximum DSL throughput: up to 24 Mbps
• Wired aggregate speed: up to 100 Mbps
• Efficient data handling for business workloads

VPN & Remote Connectivity

• Supports IPsec, L2TP, SSL VPN, and DMVPN technologies
• Secure remote access for distributed teams
• Encrypted communication across branch networks

Power & Physical Specifications

• Input voltage: AC 120/230V (50/60 Hz)
• Dimensions: 1.75 x 13.5 x 11.5 inches
• Efficient power usage for continuous operation

Overview of Cisco C1921-3G-S-SEC/K9 Ethernet Router Modular

The Cisco C1921-3G-S-SEC/K9 ISR G2 1921 Ethernet Router Modular is an advanced integrated services router designed to deliver secure scalable and high performance networking solutions for branch offices and enterprise edge environments this device is part of the Cisco 1900 Series ISR G2 platform and is engineered to combine routing security WAN optimization and modular expansion capabilities into a single unified solution enabling organizations to simplify infrastructure while maintaining reliable connectivity and strong security enforcement across distributed networks.

Dual Gigabit Ethernet Connectivity for High Speed Wired Networking

The Cisco C1921-3G-S-SEC/K9 provides dual Gigabit Ethernet interfaces that deliver high speed wired connectivity ensuring fast and stable data transfer between connected devices within branch office environments supporting critical business applications cloud based services and enterprise communication systems with consistent reliability and performance optimization.

High Throughput Data Processing for Modern Business Applications and Network

The Gigabit Ethernet ports are optimized for high throughput data processing enabling seamless operation of bandwidth intensive applications such as video conferencing large file transfers and cloud based collaboration tools ensuring uninterrupted productivity and smooth network performance across all connected systems.

Stable and Consistent Network Connectivity with Optimized Latency Control for Business Operations

The router ensures stable connectivity by minimizing latency fluctuations and maintaining consistent data flow across the network allowing organizations to rely on predictable and efficient communication between devices and services within the infrastructure.

Integrated 3G WAN Backup Connectivity for Continuous Internet Access

The Cisco C1921-3G-S-SEC/K9 includes integrated 3G WAN connectivity that serves as a backup internet solution ensuring continuous connectivity during primary WAN failures allowing organizations to maintain uninterrupted communication and operational continuity even in the event of network disruptions or service outages.

Automatic Failover Mechanism for Seamless Transition to Cellular Network Connectivity

The router supports automatic failover functionality that enables seamless switching to the 3G network when primary WAN connections fail ensuring that critical business operations remain unaffected and network availability is maintained without manual intervention or downtime.

Reliable Connectivity for Remote Deployments and Non Traditional Network Environments

The integrated 3G capability allows deployment in remote or underserved locations where traditional wired broadband may not be available providing flexible connectivity options for field offices mobile operations and temporary network setups.

Advanced Security Architecture for Comprehensive Network Protection

The Cisco C1921-3G-S-SEC/K9 ISR G2 includes a robust security architecture designed to protect enterprise networks from internal and external threats incorporating firewall capabilities VPN encryption intrusion prevention systems and secure access controls ensuring comprehensive protection for sensitive data and communication channels.

Integrated Stateful Firewall for Real Time Traffic Inspection and Threat Blocking

The built in stateful firewall provides real time inspection of network traffic identifying and blocking malicious activities while allowing legitimate data flow ensuring secure and uninterrupted network performance across all connected systems and applications.

Encrypted VPN for Secure Remote Access and Data Confidentiality Protection

The router supports secure VPN tunnels that enable encrypted communication between remote users branch offices and central networks ensuring data confidentiality integrity and secure transmission over public and private network infrastructures.

Modular Expansion for Flexible Network and Future Scalability

The Cisco C1921-3G-S-SEC/K9 features a modular architecture that allows organizations to expand and customize their network infrastructure by adding additional interface cards or service modules enabling long term scalability and adaptability to evolving business requirements and technological advancements.

Network Interface Expansion Modules for Enhanced Connectivity Options

The router supports various expansion modules that allow integration of additional WAN LAN or voice interfaces enabling organizations to extend functionality and tailor network configurations based on specific operational needs and future growth requirements.

Scalable Infrastructure Design for Long Term Investment Protection and Network Growth

The modular design ensures that organizations can scale their network infrastructure without replacing existing hardware providing long term investment protection and enabling seamless adaptation to increasing network demands and business expansion.

Routing Engine for Data Processing Network

The Cisco C1921-3G-S-SEC/K9 is equipped with a high performance routing engine that ensures efficient processing of network traffic optimized routing decisions and improved application responsiveness enabling organizations to maintain smooth operations across distributed environments and high demand network conditions.

Intelligent Traffic Prioritization for Enhanced Application Performance and Reduced Congestion

The router uses intelligent traffic management mechanisms to prioritize critical applications ensuring that essential business services receive sufficient bandwidth reducing congestion and maintaining optimal performance across all network operations.

Quality of Service Optimization for Voice Video and Data Prioritization Across Enterprise Networks

The Quality of Service capabilities allow prioritization of latency sensitive applications such as voice and video ensuring consistent performance reduced delay and improved communication quality across enterprise network environments.

Simplified Configuration and Operational

The Cisco C1921-3G-S-SEC/K9 supports centralized management tools that allow administrators to configure monitor and control network infrastructure from a single interface reducing operational complexity and improving efficiency across distributed branch environments.

Remote Network Administration for Control Across Multiple Branch Locations

The router enables remote management capabilities allowing administrators to access and configure network settings from centralized locations ensuring rapid response to issues and minimizing downtime across enterprise deployments.

Real Time Network Monitoring Tools for Performance Analysis

The device includes advanced monitoring tools that provide real time visibility into network performance enabling administrators to detect bottlenecks analyze traffic patterns and implement optimization strategies for improved efficiency and reliability.

Compact Energy Design for Flexible Deployment and Reduced Operational Costs

The Cisco C1921-3G-S-SEC/K9 ISR G2 features a compact and energy efficient design that allows deployment in space constrained environments while minimizing power consumption and reducing operational costs making it suitable for small to medium sized branch office deployments requiring efficient resource utilization.

Space Hardware Design for Easy in Office and Branch Environments

The compact chassis design allows easy installation in limited space environments ensuring quick deployment and integration into existing network infrastructure without requiring significant physical modifications or additional equipment.

Consumption for Cost and Environmentally Sustainable Operations

The energy efficient architecture reduces power usage contributing to lower operational costs and supporting environmentally sustainable IT infrastructure strategies for modern organizations.

Enhanced Business Continuity Through Redundant Connectivity

The Cisco C1921-3G-S-SEC/K9 ensures business continuity by providing redundant connectivity options secure communication channels and reliable routing performance enabling organizations to maintain operations during network disruptions or unexpected failures while ensuring consistent access to critical applications and services.

Seamless Network Failover for Continuous Connectivity and Uninterrupted Operations

The router supports automatic failover between primary WAN connections and backup 3G connectivity ensuring continuous network availability and minimizing downtime during service interruptions or infrastructure failures.

Reliable Communication Infrastructure for Enterprise Applications

The system ensures stable and secure communication infrastructure for mission critical applications enabling organizations to maintain productivity and operational efficiency even under high demand or adverse network conditions.

Improved Enterprise Collaboration Through Secure

The Cisco C1921-3G-S-SEC/K9 enhances enterprise collaboration by providing secure high performance networking capabilities that enable seamless communication and data sharing across distributed teams ensuring consistent productivity and operational efficiency across business environments.

Data Sharing and Communication Across Branch and Remote Offices

The router enables efficient data sharing and communication between branch offices and central systems ensuring seamless collaboration and access to critical business resources across geographically distributed teams.

Workflows and Enterprise Grade Communication Systems

The device ensures continuous support for mission critical workflows and communication systems enabling organizations to maintain reliable operations and consistent service delivery across all business processes and applications.