VMware Horizon Security Server is a custom instance of the Horizon Connection Server that is designed to be installed in a datacenter Demilitarized Zone (DMZ), in order to provide strong levels of authentication and secure access for Horizon clients connecting from outside the organization's private network. Multiple Security Servers may be installed to provide load balancing and high availability to these external clients.

The following diagram shows the placement of a Horizon Security Server or Unified Access Gateway (discussed next) within a DMZ:

Horizon Security Server is installed on top of a supported version of Microsoft Windows' Server using the same installation package used for Horizon Connection Servers. Horizon Security Server is only required if providing access to Horizon clients residing outside of the company network. Chapter 4, Implementing Horizon Security Server, provides the information needed to install and configure a VMware Horizon Security Server.