United StatesName:
Added to cart 28 times recently
In stock - Ready to Ship
$3,745.00
$1,970.0047.4% off
Quantity:
Business price:
3 Year Extended Warranty
Same-day Shipping
14-Day Money Back Guarantee
Shipping:
Payment:
3 Year Extended Warranty
Same-day Shipping
14-Day Money Back Guarantee
Need Additional Discount on Product?
Request a quote below - Get Exclusive Pricing and Support.
Shipping:
Payment:
C1-CISCO4321/K9
Cisco ONE ISR 4321 (2GE.2NIM.4G FLASH.4G DRAM.IPB)
TRUSTED, TRIED, PROVEN
Inventory Delivered By
& Verified By
Solutions Powered By
C1-CISCO4321/K9 is an enterprise-class integrated services router engineered with a modular architecture that supports a wide array of integrated services including voice, video, and WAN optimization. Built to deliver robust security and reliable connectivity, this router efficiently handles VPN features, advanced routing protocols, and firewall functions while ensuring performance and redundancy in mission‐critical applications.
C1-CISCO4321/K9 comes with versatile power options featuring an AC power supply with redundant capabilities, and its dual WAN configuration alongside modular LAN interfaces provide flexible connectivity. Designed for secure, high-performance networking, it offers integrated VPN support, high availability, and throughput capacity tailored to demanding enterprise and branch office use cases.
C1-CISCO4321/K9 price is $1,970.00, a 47.4% saving from the Cisco list price of $3,745.00. C1-CISCO4321/K9 is in stock and available for next-day dispatch. (terms applied)
Request bulk order quote for C1-CISCO4321/K9 for additional pricing. Browse the full Router Isr 4000 series or explore all Cisco products.
A national retail chain deploys Cisco ONE ISR 4321 (C1-CISCO4321/K9) routers at 100 locations to establish dynamic SD-WAN overlays and encrypted DMVPN connections to the corporate data center, optimizing POS transactions and inventory updates over dual 1 GbE links. Advanced QoS and IP routing modules ensure sub-10 ms failover while reducing MPLS leased-line costs by 45%. Benefit: Scalable, resilient branch connectivity with 99.99% availability and lower operational expenses.
A global financial services firm leverages the C1-CISCO4321/K9 Cisco ONE ISR 4321 to provision secure IPsec tunnels and BGP peering directly into AWS VPC and Azure ExpressRoute, providing low-latency access to Salesforce, Office 365, and trading platforms. Dual NIM slots support concurrent encryption and virtualized services, maintaining sub-20 ms WAN latency and ensuring compliance with FINRA regulations. Benefit: Accelerated SaaS performance, streamlined cloud migration, and robust security posture.
An automotive manufacturer integrates C1-CISCO4321/K9 Cisco ONE ISR 4321 routers at multiple factory floors to segment Industrial IoT devices, PLC networks, and guest Wi-Fi using Zone-Based Firewall and VLAN tagging, while enabling 4G LTE backup for zero downtime. Built-in threat intelligence and real-time monitoring automate intrusion prevention and maintain continuous production line operations. Benefit: Enhanced IoT security with a 30% reduction in cyber incidents and uninterrupted manufacturing processes.
To get the detailed certification, please go to the Compliance Center.
| C1-CISCO4321/K9 |  C1-CISCO4451/K9 |  ISR4451-X/K9 |  ISR4331-AX/K9 |  ISR4461-AXV/K9 | |
|---|---|---|---|---|---|
| 5G Support | No | No | No | No | No |
| Architecture | Modular | Modular | Modular | Fixed / Modular | Modular |
| Broadband | N/A | N/A | N/A | N/A | N/A |
| Built-in Security Features | Firewall / Intrusion Prevention | Firewall, Intrusion Prevention, Malware Protection | Firewall / Intrusion Prevention / Malware Protection | Firewall / Intrusion Prevention / Malware Protection | Firewall / Intrusion Prevention / Malware Protection |
| Compliance Standards | FCC / CE | FCC, CE | FCC, CE | FCC / CE / UL | FCC / CE / UL |
| Connectivity Type | Wired | Wired | Wired | Wired | Wired |
| Depth | 20 inches | 18 inches | N/A | N/A | N/A |
| Device Type | Router | Router | Router | Router | Router |
| EMC | N/A | N/A | N/A | FCC / CE | N/A |
| Ethernet Technology | 10/100/1000 | 10/100/1000 | 10/100/1000 | 10/100/1000 | 10/100/1000 |
| Expansion Slots | NIM / EHWIC | EHWIC / NIM | NIM / EHWIC | EHWIC / NIM | EHWIC / NIM |
| Features | VPN / VoIP / IPv6 Compatible / Firewall / WAN Optimization | VPN, VoIP, IPv6 Compatible, Firewall, MPLS | VPN / Voice / Video / Firewall / MPLS / WAN Optimization | VPN / IPv6 Compatible / Firewall / WAN Optimization / Voice / Video | VPN / Firewall / IPv6 Compatible / QoS |
| Firewall Features | Yes | Yes | Yes | Yes | Yes |
| Flash Memory | 512 MB | 2 GB | 2 GB | 512 MB | 1 GB |
| Form Factor | Rack-mount | Rack-mount | Rack-mount | Rack-mount | Rack-mount |
| Height | 1.75 inches | 1.75 inches | N/A | N/A | N/A |
| High Availability Support | Supported | Supported | Supported | Supported | Supported |
| Integrated Services | Voice / Video / WAN Optimization | Voice, Video, WAN Optimization | Voice / Video / WAN Optimization | Voice / Video / WAN Optimization | Voice / Video / WAN Optimization |
| Interface Ports | RJ-45 / SFP | RJ-45, SFP, Combo Ports | RJ-45 / SFP | RJ-45 / SFP | RJ-45 / SFP / Combo Ports |
| LAN Ports | Modular LAN | Modular LAN | 4 LAN Ports | 4 LAN Ports | 4 LAN Ports |
| Management | Managed | Managed | Managed | Managed | Managed |
| Memory | 1 GB | 4 GB | 4 GB | 4 GB | 4 GB |
| Modular Slots Available | 2 Slots | 3+ Slots | 2 Slots | 3+ Slots | 3+ Slots |
| Network Protocols | IPv4, IPv6 | IPv4, IPv6 | IP, IPv6, OSPF, EIGRP, BGP, RIP, MPLS | IPv4 / IPv6 | IPv4 / IPv6 |
| Power | 110 W | 250 W | 375 W | 65 Watts | 370W |
| Power Source | AC Power Supply with Redundant Options | AC Power Supply / Redundant | AC Power Supply / DC Power Supply / Redundant | AC Power Supply | AC Power Supply / Redundant |
| Product Name | Cisco 4321 Integrated Services Router (C1-CISCO4321/K9) | Cisco 4451 Integrated Services Router | Cisco ISR 4451-X/K9 | Cisco ISR4331-AX/K9 | Cisco ISR 4461 Integrated Services Router |
| Product Type | Enterprise Router | Enterprise Router | Enterprise Router | Enterprise Router | Enterprise Router |
| QoS Features | Supported | Supported | Supported | Supported | Supported |
| Remote Management | SSH / Telnet / SNMP | CLI, SNMP, Telnet, SSH | CLI / SNMP / NetConf | SSH / Telnet / SNMP | SSH / Telnet / SNMP |
| Routing Protocols | OSPF / BGP / EIGRP / RIP / Static Routing | OSPF / BGP / EIGRP / MPLS / IS-IS / RIP / Static Routing | OSPF / BGP / EIGRP / MPLS / RIP / Static Routing | OSPF / BGP / EIGRP / MPLS / RIP / Static Routing | OSPF / BGP / EIGRP / IS-IS / RIP / Static Routing |
| Safety | N/A | N/A | N/A | UL / IEC | N/A |
| Speed/Capacity | Gigabit | Gigabit | Gigabit | Gigabit | Gigabit |
| Stacking Capability | No | No | No | No | Yes |
| Telecom | N/A | N/A | N/A | TIA/EIA | N/A |
| Throughput Capacity | 0.15 Gbps | 2 Gbps | 2 Gbps | 0.15 Gbps | 1 Gbps |
| Use Case | Enterprise | Enterprise | Enterprise | Enterprise / Branch | Enterprise |
| VPN Support | IPSec / SSL VPN / DMVPN / FlexVPN | IPSec / SSL VPN / GRE / DMVPN / FlexVPN / N/A | IPSec / SSL VPN / DMVPN / FlexVPN | IPSec / SSL VPN / DMVPN / FlexVPN | IPSec / SSL VPN / DMVPN / FlexVPN |
| WAN Configuration | Dual WAN | Dual WAN | Dual WAN | Dual WAN | Dual WAN |
| WAN Ports | 2 WAN | Modular WAN | 2 WAN | 2 WAN | 2 WAN |
| Weight | 14 lbs | 23 lbs | N/A | N/A | N/A |
| Wi-Fi Standard | N/A | N/A | N/A | N/A | N/A |
| Width | 17.5 inches | 17.5 inches | N/A | N/A | N/A |
| Wireless Support | No | No | No | No | No |
Cisco ONE licensing made rollout simple. Performance has been stable and well suited for branch routing needs.
Reliable ISR for small branches. Easy to manage and integrates smoothly into existing Cisco environments.
Consistent uptime and predictable performance. A solid entry level enterprise router.
Straightforward deployment with good routing capacity. Meets daily business requirements.
Cisco quality hardware with dependable results. No operational issues so far.
The Cisco ONE ISR 4321 is an integrated services router featuring two Gigabit Ethernet ports, two NIM slots, 4 GB flash, 4 GB DRAM, and an IP Base license, designed for secure, high-performance, and scalable connectivity in small branch and enterprise edge networks.
The Cisco ONE ISR 4321 delivers up to 50 Mbps encrypted throughput with a dual-core 1.2 GHz CPU, two GE ports, two NIM slots, 4 GB DRAM, 4 GB flash, IP Base licensing, and support for Cisco DNA Center and SD-WAN features.
The product includes the IP Base license and supports optional IP Services, Security, and AppX licenses for advanced routing, VPN, firewall, and application optimization, allowing tailored feature sets to match evolving network demands.
Mount the ISR 4321 on a rack or wall plate, connect AC or optional DC power, attach network cables to the GE ports, access the Cisco IOS CLI via console for initial configuration, and deploy WAN, LAN, and security settings using Prime Infrastructure or Cisco DNA Center.
The ISR 4321 offers up to 50 Mbps of IPsec VPN throughput, 100 Mbps of aggregate data routing, up to 25,000 concurrent sessions, and hardware-accelerated encryption, ensuring reliable performance in small branch and enterprise edge scenarios.
Cisco ONE ISR 4321 supports two NIM slots compatible with serial, T1/E1, xDSL, 4G LTE, and fiber WAN modules, delivering flexible connectivity options to meet diverse branch office requirements.
Yes, with the optional Cisco SD-WAN subscription, the ISR 4321 enables zero-touch provisioning, centralized policy control, secure overlay tunnels, and application-aware routing across multiple WAN links.
The router integrates stateful and zone-based firewalls, IPsec VPN encryption, Secure Boot, a Trusted Platform Module, and optional Cisco Umbrella DNS protection, providing multi-layered defense for branch offices.
The ISR 4321 consumes up to 28 Watts, supports AC and optional DC power inputs, and features an energy-efficient design that complies with global safety and electromagnetic standards.
It operates between 0–40 °C (32–104 °F) at 10–90% non-condensing humidity, meets NEBS Level 3 and ETSI standards, and is suitable for standard office and telecom room environments.
It offers redundant WAN connectivity via dual GE ports or NIM modules, supports HSRP for gateway failover, and allows dual power inputs to ensure uninterrupted network service.
You can manage the ISR 4321 via Cisco IOS CLI, Cisco Prime Infrastructure, Cisco DNA Center, SD-WAN vManage, and RESTful APIs for streamlined deployment, configuration, and monitoring.
Cisco provides a limited lifetime hardware warranty with 8×5×NBD replacement; software updates, advanced technical support, and enhanced SLAs are available through Cisco SMARTnet service contracts.
Yes, you can expand the DRAM up to 8 GB with Cisco-approved SODIMM modules and increase flash storage by installing a higher-capacity flash module in the dedicated flash slot.
Use cases include secure branch routing, SD-WAN edge, VPN gateway, voice and video services, cloud connectivity, and managed service applications for small offices and retail environments.
Define IKEv2 policies, pre-shared keys or certificates, and crypto maps using the CLI or Prime Infrastructure, then apply these configurations to the WAN interface to establish secure IPsec VPN tunnels.
You can order the Cisco ONE ISR 4321, power supplies, network modules, and software licenses from Cisco authorized resellers, the Cisco online store, and vetted partner marketplaces.