ISR4321 K9 Cisco Network Interface Module
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ISR4321/K9 Cisco ISR 4321 2 Ports 4 Slots Security Router Refurbished

Availability: In Stock
Part Number#: ISR4321/K9
List Price was: $900.00
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Short Description:
ISR4321/K9 Integrated Service Router (ISR) Series 2 Ports 4 Slots Rack-Mountable, Wall Mountable Gigabit Ethernet Security Router | Made by Cisco | Refurbished
Product Condition:
Warranty provided by ALLHDD.COM:
90 Days

More Information

The Cisco ISR 4321 is a router designed for small and medium-sized businesses, enterprise branch offices, and service provider edge applications. It is equipped with 2 network interface slots and 4 service module slots, which can be used to add a variety of connectivity and services options. The router is powered by a dual-core Intel Xeon processor and has 2GB of RAM and 8GB of flash memory, making it capable of handling a wide range of routing, security, and data services applications. It also supports Cisco IOS XE software, which provides a flexible and scalable platform for implementing advanced routing and services functions.

Some of the key features of the Cisco ISR 4321 include:

  • Support for a wide range of connectivity options, including Ethernet, serial, and WAN interface cards.
  • Integration with Cisco security technologies, such as firewall, VPN, and content filtering.
  • Advanced Quality of Service (QoS) features for optimizing voice and video traffic.
  • Support for Cisco IOS XE software, which provides a flexible and scalable platform for implementing advanced routing and services functions.
  • Integration with Cisco Network Assistance, a powerful tool for managing and configuring the router.
  • Support for a range of applications, including routing, security, voice, and video.

High Availability Features of the ISR4321/K9 Cisco ISR 4321 Router

The Cisco ISR 4321 security router supports several high availability (HA) features that help ensure continuous network operation in the event of a hardware or software failure. Some of the key HA features supported by the ISR 4321 include:

  • Stateful Switchover (SSO): This feature provides a mechanism for the router to switch over to a standby processor in the event of a primary processor failure. The standby processor maintains a synchronized state with the primary processor, so there is no loss of data during the switchover.
  • Hot Standby Router Protocol (HSRP): This feature provides automatic failover for IP networks by allowing a set of routers to share a virtual IP address. In the event of a router failure, the standby router can take over the virtual IP address and continue forwarding packets.
  • Virtual Router Redundancy Protocol (VRRP): Similar to HSRP, VRRP allows a set of routers to share a virtual IP address. However, VRRP allows for more than two routers to participate in the redundancy group, providing greater scalability.
  • Gateway Load Balancing Protocol (GLBP): This feature provides load balancing and redundancy for IP traffic by allowing multiple routers to share a virtual IP address. GLBP can distribute traffic across multiple paths, and can also provide automatic failover in the event of a router failure.
  • Network Address Translation (NAT) redundancy: This feature provides redundancy for NAT configurations by allowing multiple routers to share NAT translations. If one router fails, the other router can take over the NAT translations.

To implement these HA features on the Cisco ISR 4321, you will need to follow the specific configuration instructions provided by Cisco. The configuration guides and documentation available on the Cisco website provide step-by-step instructions on how to configure these features on the ISR 4321. It is also recommended to consult with a Cisco certified network engineer for assistance with configuring high availability on your network.

WAN Connectivity Options of the ISR4321/K9 Cisco ISR 4321 Router

The Cisco ISR 4321 router is a highly capable network device that offers a range of WAN connectivity options to suit different requirements. Some of the WAN connectivity options available for the ISR 4321 include:

  • Ethernet WAN: The ISR 4321 router comes with two built-in Gigabit Ethernet WAN ports that can be used to connect to high-speed broadband Internet services. These ports can be used with different types of WAN technologies, including DSL, cable, and fiber.
  • T1/E1 WAN: The ISR 4321 also supports T1/E1 WAN connectivity using the built-in HWIC-2T1/E1 module. This allows for the use of leased lines or other types of dedicated circuits for WAN connectivity.
  • Serial WAN: The ISR 4321 can also support legacy serial WAN connectivity using the built-in HWIC-2T module. This allows for the use of synchronous or asynchronous serial connections for WAN connectivity.
  • LTE Wireless WAN: The ISR 4321 can support wireless WAN connectivity using a Cisco LTE module, such as the Cisco EHWIC-4G-LTE or Cisco EHWIC-4G-LTE-G. This allows for high-speed mobile broadband connectivity using cellular networks.
  • Satellite WAN: The ISR 4321 can also support satellite WAN connectivity using the built-in HWIC-4B-S/T module. This allows for the use of satellite-based connectivity for remote sites or locations where terrestrial connectivity is not available.

To determine the most appropriate WAN connectivity option for your network, you should consider factors such as bandwidth requirements, geographic location, availability of service providers, and cost. It may also be helpful to consult with a Cisco certified network engineer to help you evaluate your options and design a network that meets your specific needs.

General Information about the Cisco ISR4321/K9

  • Manufacturer: Cisco
  • Part Number or SKU # ISR4321/K9
  • Product Series: 4000
  • Product Model: 4321
  • Product Name: 4321 Router
  • Product Type: Router

Technical Information of Router 4000 Series

  • Total Number of Ports: 2
  • USB: Yes
  • Powerline: No
  • Management Port: Yes
  • Serial V.35 Interface: No
  • Number of Network (RJ-45) Ports: 2

I/O Expansions for 2 Ports Integrity Service Router

  • Number of Total Expansion Slots: 4
  • Expansion Slot Type: Smart Interface Card (SIC)
  • Expansion Slot Type: Network Interface Module (NIM)
  • Expansion Slot Type: SFP

Network & Communication of SFP Router

  • Network Technology: 10/100/1000Base-T
  • Ethernet Technology: Gigabit Ethernet

Management & Protocols

  • Security Features:
  • ACL
  • AAA
  • IPsec

Memory ISR4321 K9

  • Standard Memory: 4 GB
  • Maximum Memory: 8 GB
  • Memory Technology: DDR3 SDRAM
  • Flash Memory: 4 GB
Power Description
  • Input Voltage 230 V AC
  • Input Voltage 120 V AC
  • Power Source PoE
  • Power Source Power Supply
  • Redundant Power Supply No
Dimensions & Weight
  • Width: 14.6 Inch
  • Depth: 11.6 Inch
  • Height: 1.8 Inch
  • Weight: 7.72 Lbs

About Refurbished Products

Refurbished products are typically refurbished by an Original Manufacturer or an affiliate of the manufacturer or 3rd party facility. This product may have minor blemishes due to normal product usage and doesn't necessarily come with documentation and software unless indicated, but has been well tested and generally has never had any defects.

Routers lead the line as the first line of network security in homes and offices. It prevents intrusion into a network while creating a firewall to provide the highest level of security on several network types. They are the best ways of keeping computer systems, network systems, and information contained in them safe from intrusion.

A router is designed to be more capable than several other network devices such as hubs or switches that can only carry out basic network functions. For instance, a hub only transfers data between network devices without analyzing or doing anything with those data. On the other hand, routers are able to analyze data sent between network devices. They can change the packaging of such data and send it over to a different network.

Routers are the perfect devices to share an internet connection between multiple computers in home networks. A router typically connects to the modem using a network cable. Router networking occurs via a WAN port or the internet. There are also wireless routers that connect to devices using different wireless standards.

Important Features

Multi-core Processor

The hardware inside these routers allows them to cope with several network use at the same time. Many of these routers come with dual-core and quad-core processors. These processor options allow them to handle lots of data more effectively. Users can use their Wi-Fi routers for activities such as video streaming, online gaming, data backups, and more. Even while carrying out those operations, the routers perform at the highest levels.

Multi-band options

Users will get routers that broadcast wireless signals over two frequencies (for dual-band) or more (for tri-band and others). These routers run at frequencies that can cover a wide expanse of area. They are not congested and are perfect for office buildings, homes, and large enterprises. Clients will find routers that emit their signals between 2.4 GHz and 5 GHz.

Built-in Security Features

These router networking devices also come with security features such as device quarantine, firmware updates, automatic updates, and more. The features allow them to provide network-level protection against attacks. With these features, cyber criminals will be unable to infiltrate home networks.

Types of Routers

There are several types of routers that users can benefit from. Some of them include:

  • Core Routers. These are the types used by Internet Service Providers. They are the fastest and most powerful types. They sit at the center of the internet and forward data through the main fiber Optics.
  • Wireless Routers. These work in a similar manner as a home or business LAN. However, they give room for better mobility for laptops, tablets, and other portable devices. These types offer transmission over short distances.
  • Enterprise Routers. These are the types employed by large companies. Organizations use enterprise routers to connect their networks to these core routers.
  • Branch Routers. These types connect an enterprise's remote offices to its Wide Area Network (WAN). They come with improved features such as wireless LAN management, time-division multiplexing, WAN acceleration, and more.
  • Edge Routers. These are the most commonly used types in homes and small businesses. They are low-capacity devices that connect to the public internet or private WAN, or external LAN.
  • Logical Routers. They function similarly to hardware to create several network routes.

Here, you can check more available conditions of your desired product ISR4321/K9 at a competitive price. We are trying our best to meet your needs on the enterprise-level computer, server, data centre, and networking hardware. You are welcome to ask our live chat or get live representative support over the phone.


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ALLHDD guarantees that the products will not have defects in material that will affect the product's functionality during the Standard Warranty Period. The warranty period starts when the merchandise/items from our warehouse.

What does ALLHDD.Com warranty cover?

30-days to 3 years warranty:

Replacement or refund. In the case of material defects, we will try to replace the product first. The product will be replaced before the expiration of the original warranty. For any failure of hardware, if we cannot process the replacement of the product(s)/model(s), we will refund the original selling/invoiced price. The shipping costs and sales tax, if any, are non-refundable. ALLHDD retains the right to decide whether the item(s) will process for replacement or refund.

What is not covered by our warranty?

The reason why our warranty does not cover any problem caused by the following conditions:

(a) misuse of hardware; accidental damage; carelessness product(s) damage; shock; temperature beyond the specification of any product; faulty installation; operation; modification of goods;

(b) any misuse outside the instructions in the user manual for any specific product;

(c) damaged caused by other hardware or equipment. The warranty will void if the item is returned with physical damage, damage to the retail box, removed from the box, counterfeit labels/labelled by them, or any modifications of internal and external covers. Data loss or damages to any other equipment we do not cover by our offered warranty.

What is the Manufacturer/Brand Warranty?

In general, a manufacturer's warranty service/support is a written guarantee to the buyer of a product. Its terms assure the replacement or repair of the product, if necessary, within a specified period after the purchase (2-5 years depending on the brand/manufacturer). It is typically included in the price of the product. Products are brand new and sealed and the original manufacturer box is complete with the Manufacturer's genuine warranty. For most of the brand new/retail products that come with the manual and box, exceptions may apply (i.e., Cisco, Juniper Networks).

For the server parts (i.e., Dell, HPE) to get Full coverage of the warranty server must have a full 3- 5 years warranty. However, ALLHDD.COM will cover the warranty duration if any Manufacturer doesn't support the advertised warranty and there is no refund for those.
Final Sale items are non-returnable/refundable in any situation. Any question? please ask our team before the shipment.

Important notes:

We can provide additional warranty service/support for any product you purchase from us if you need additional warranty coverage before finalizing the order from ALLHDD.Com. You need to ask in live chat/help or call us for more information.

Individual product warranty mentioned on each item product description page/detail page.

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