Cisco Systems ISR4431/K9 Integrated Services Router

The Cisco ISR4431/K9 Integrated Services Router is a modular enterprise router designed for branch offices, remote sites, and WAN network environments, delivering secure data routing and advanced network services to support VPNs, cloud access, VoIP, and distributed applications. Commonly installed in corporate branches and service edge deployments where reliable connectivity and scalable performance are required, it offers up to 500 Mbps throughput (upgradeable with licenses) and modular expansion through 3x Gigabit Ethernet RJ-45 ports, 2 NIM slots, and 1 Service Module slot, with 4 GB DRAM (expandable) and 4 GB flash storage (expandable). Routing features include BGP, OSPF, MPLS, and VPN support, while security features encompass an integrated firewall, IPSec VPN, and encryption. Management is provided via Cisco IOS XE, CLI, and SNMP, the unit is rack-mountable in 1U with an internal AC power supply, and common replacements include Cisco ISR4451-X/K9, ISR4321/K9, and ISR4351/K9.