Wikipedia
Vyatta provides software-based virtual router, virtual firewall and VPN products for Internet Protocol networks ( IPv4 and IPv6). A free download of Vyatta has been available since March 2006. The system is a specialized Debian-based Linux distribution with networking applications such as Quagga, OpenVPN, and many others. A standardized management console, similar to Juniper JUNOS or Cisco IOS, in addition to a web-based GUI and traditional Linux system commands, provides configuration of the system and applications. In recent versions of Vyatta, web-based management interface is supplied only in the subscription edition. However, all functionality is available through KVM, serial console or SSH/telnet protocols. The software runs on standard x86-64 servers.
Vyatta is also delivered as a virtual machine file and can provide (vrouter, vfirewall, VPN) functionality for Xen, VMware, KVM, Rackspace, SoftLayer, and Amazon EC2 virtual and cloud computing environments. As of October, 2012, Vyatta has also been available through Amazon Marketplace and can be purchased as a service to provide VPN, cloud bridging and other network functions to users of Amazon's AWS services.
Vyatta sells a subscription edition that includes all the functionality of the open source version as well as a graphical user interface, access to Vyatta's RESTful API's, Serial Support, TACACS+, Config Sync, System Image Cloning, software updates, 24x7 phone and email technical support, and training. Certification as a Vyatta Professional is now available. Vyatta also offers professional services and consulting engagements.
The Vyatta system is intended as a replacement for Cisco IOS 1800 through ASR 1000 series Integrated Services Routers (ISR) and ASA 5500 security appliances, with a strong emphasis on the cost and flexibility inherent in an open source, Linux-based system running on commodity x86 hardware or in VMware ESXi, Microsoft Hyper-V, Citrix XenServer, Open Source Xen and KVM virtual environments.
In 2012, Brocade Communications Systems acquired Vyatta and renamed it "Vyatta, a Brocade Company". In April, 2013, Brocade renamed the product from the Vyatta Subscription Edition (VSE) to the Brocade Vyatta 5400 vRouter. The latest commercial release of the Brocade vRouter is no longer open-source based.