## Terms and Abbreviations Used in This Guide The following terms and abbreviations are used in this guide:
Term/Abbreviation | Description
RAS Console | Parallels Remote Application Server Console. The RAS Console is the primary interface you use to configure, manage, and run Parallels Remote Application Server. As an administrator, you use the RAS Console to manage farms, sites, terminal servers, published resources, client connections, etc.
Category | In the RAS Console, categories are displayed in the left pane of the main interface. Each category consists of a number of settings related to a specific task or operation. The categories include Start, Farm, Load Balancing, Publishing, Universal Printing, Universal Scanning, Connection, Client Manager, and others.
Farm | A Parallels RAS farm is a logical grouping of objects for the purpose of centralized management. A farm configuration is stored in a single database which contains information about all objects comprising the farm. A farm consists of at least one site, but may have as many sites as necessary.
Site | A site consists of at least one RAS Publishing Agent, RAS Secure Client Gateway (or multiple gateways), and RAS agents installed on Terminal Servers, virtualization (VDI) hosts, and Windows PCs. Note that a given Terminal Server, VDI host, or PC can be a member of only one site at any given time.
Licensing Server Site | The site where the main configuration database is stored and manages all other sites in the RAS farm. Other servers in a site can be upgraded to Licensing Server if the main licensing server is not available. Note: Upgrades of the Parallels Remote Application Server MUST be applied to the licensing server site first.
RAS Secure Client Gateway | RAS Secure Client Gateway tunnels all traffic needed by applications on a single port and provides secure connections.
HTML5 Client | HTML5 client allows users to view and launch remote applications and desktops in a web browser. The HTML5 client functionality is a part of RAS Secure Client Gateway.
Publishing | The act of making items installed on a Remote Desktop Server, VDI host or Remote PC available to the users via the Parallels Remote Application Server.
RAS Publishing Agent | RAS Publishing Agent provides load balancing of published applications and desktops.
RAS Terminal Server Agent | RAS Terminal Server Agent collects information from the MS RDS hosts required by the Publishing Agent and transmits to it when required.
RAS PC Agent | RAS PC Agent collects information from Remote PC hosts required by the Publishing Agent and transmits to it when required.
RAS Guest VM Agent | RAS Guest VM Agent collects information from the VDI desktop required by the Publishing Agent and transmits to it when required.
RAS VDI Agent | RAS VDI Agent collects information from the Parallels Remote Application Server Infrastructure and is responsible for controlling VDI through its native API. It also acts as a gateway between the Secure Client Gateway or the client in direct mode and the RDP server from the guest VM or VDI depending on VDI implementation.
RAS Web Portal | RAS Web Portal is a web page with auto client detection and a client distribution point. It provides access to published resources via web browser.
RDS | Remote Desktop Services is a Microsoft Windows component that makes applications and the entire desktop of a server running RDS accessible to a remote client device that supports Remote Desktop Protocol (RDP). RDS replaced Terminal Services beginning with Windows 2008 R2.
Terminal Services | See RDS above.
HALB | HALB (High Availability Load Balancing) is a software solution that sits between users and Parallels Secure Client Gateways. Many HALB appliances can run simultaneously, one acting as the master and the others as slaves. The higher the number of HALB appliances available, the lower the probability that users will experience downtime. Master and slave appliances share a common or virtual IP, also known as VIP. Should the master HALB appliance fail, a slave is promoted to master and takes its place seamlessly without affecting the end user's connection.