[1] The company developed the world's first firewall purpose-built for virtual networks, a software security "appliance" that runs in a virtualized environment and enforces security policy on a per-virtual-machine basis.

Headquartered in Redwood Shores, California, United States, Altor was founded in 2007 by security and networking experts from Check Point Software, Cisco and Oracle Corporation, and has received funding from Accel Partners, DAG Ventures, Foundation capital, and Juniper Networks.

Altor released the Virtual Network Security Analyzer (VNSA) as a tool to monitor and analyze virtual network traffic in March 2008, followed on by the Altor VF 1.0 (which included the VNSA as a module) in October 2008.

Integrated signature-based network intrusion detection was incorporated into the Altor VF 3.0 release in September 2009.

Altor Networks offers a virtual security appliance for use within VMware ESX, with ongoing efforts to add support for Xen/Citrix and Microsoft HyperV/Viridian platforms.