Visual DataFlex is now !

This website,, is being retired, and will eventually be shut down.
Please visit for the latest DataFlex product information.

DataFlex WebApp Server Licensing

The DataFlex WebApp Server powers dynamic, fast, secure, web database applications running on Microsoft Windows Server platforms.

A DataFlex WebApp Server includes the web application execution engine, various utilities, the embedded database and SQL database connectivity (extra cost for some license options). A DataFlex WebApp Server license is required for each server operating system instance on which the software is installed. For licensing purposes, a server operating system instance is a hardware server with one operating system installed or a server instance running a supported operating system in any form of premise-based or cloud-based virtual machine. Any server operating system instance requires its own, unique DataFlex WebApp Server license and registration code. See the product License Agreement for complete details, terms and conditions.

In a hurry?

  • Read the DataFlex WebApp Server Licensing FAQ.
  • View the DataFlex WebApp Server Licensing Infographic.

Want more details?

  • Watch video of the DataFlex WebApp Server Licensing webinar hosted by Data Access president Chip Casanave that demonstrates how specific licensing scenarios may be best applied to your deployments.
  • View the webinar's presentation slides.
  • Read the Visual DataFlex 2013 / 17.1 & DataFlex WebApp Server & Electos Policy Addendum.
For personal assistance with determining your licensing needs, please contact your regional Data Access representative.

Details about DataFlex WebApp Server Licensing

New DataFlex WebApp Server licenses include a one-year Subscription. Annual subscription renewals provide DataFlex WebApp Server users with all updates and enhancements for one year.

Licensing Forms
Since the design and function of web applications and the profile of those that use them varies so widely, several forms of deployment license are offered for the DataFlex WebApp Server:

Web Client Licensing
The DataFlex Web Framework is designed to build fully functional, browser-based business applications with desktop-like functionality. Many web business apps have similar-to-Windows usage and user profiles (users are known, managed, configured and granted rights by an administrator). Accordingly, a new licensing concept called “Web Clients” is now available as of version 2012 / 17.1.

A Web Client License entitles a named end user to use the resources of a DataFlex WebApp Server. This license is the web equivalent of Visual DataFlex Windows Client Licenses for desktop applications. For both Windows and web deployments, a license is required for each user of the software.
The benefits of Web Client Licenses are:

DataFlex WebApp Server Licensing FAQ
Read the WebApp Server
Licensing FAQ



View the DataFlexWebApp Server Licensing Overview presentation slides 
View the DataFlex
WebApp Server Licensing
Overview presentation

  • The “client” licensing concept is familiar to Visual DataFlex customers.
  • Its cost is directly proportional to the number of users of the web application.
  • There is no separate license cost for the DataFlex WebApp Server – all fees are based on the named user clients. Web clients are entitled to the full unrestricted resources of the licensed server. A unique registration code is required for each server running applications for Web Clients. Servers supporting Web Clients can be connected to an SPLF Server (details below).
  • The lack of a cost for the underlying DataFlex WebApp Server allows small use web applications or applications for small companies to be deployed inexpensively and competitively.
  • With a decreasing cost per user as the Web Client user count increases, large-scale deployments are economically balanced and feasible.
  • All Web Client Licenses include database connectivity
Software-as-a-Service (SaaS) business solutions can be deployed using Web Client Licensing. Questions about SaaS licensing and pricing should be directed to your Data Access Worldwide Channel Partner, Regional Office or headquarters in Miami, Florida, USA.
Windows/Web Combo Client Licensing
To simplify deployments where both Windows Clients and Web Clients will be required for the same end users, a single “Combo” license that provides entitlement to use both for a single price is now available. Combo licenses are named user licenses that include connectivity.
Some web applications do not have defined or managed users. Users may be self-defining or non-recurring, or an on-going user identity may not be part of the application’s functionality or design concept at all. To accommodate such applications and database driven web sites, another new concept is now available: Web Application Licensing.
With Web Application Licensing, there is a basic fee for the DataFlex WebApp Server that includes entitlement to run one application. Thereafter, a smaller fee is charged for each application run on the same server. With Web Application Licensing, there is no restriction on the number of users or any requirement for user identity at all. The server instance and number of applications running on it are the only elements that determine the license fee.
The benefits of Web Application Licenses are:
  • Simplicity
  • Server efficiency – multiple applications for different users can be run on one server instance
  • Flexibility – other than the number of applications, there are no restrictions on Web Application Licensed servers – any number of users or any number of processes can be run according to hardware capacity and application requirements
  • Low administration (no user counting)
  • Cost is scaled to the number of applications run on the server
  • Well suited for hosting providers supporting multiple clients’ applications
  • Adding database connectivity to Web Application Licensed servers is easy and economical
In the context of DataFlex WebApp Server Licensing, a Web Application is one executable (by default webapp.exe) running in a web share on a licensed DataFlex WebApp Server. Technically, each Web Application is one entry in the DataFlex WebApp Administrator utility. Creating the web share for the executable and adding it with the WebApp Administrator “registers” the application. Each registered Web Application must be counted for this form of license. A complete web business solution may be made up of one, two or several Web Applications.
Software-as-a-Service (SaaS) business solutions cannot be deployed using Web Application Licensing. Questions about SaaS licensing and pricing should be directed to your Data Access Worldwide Channel Partner, Regional Office or headquarters in Miami, Florida, USA
DataFlex WebApp Server Lite
A special, restricted "Lite" license is now provided to deploy small-scale DataFlex Web Framework or web service solutions. Called the DataFlex WebApp Server Lite, this license allows only one application and one server process to be executed. The restrictions intentionally throttle server performance but, at its low price, there is a balance between cost and capability.
DataFlex WebApp "SPLF" Server 
"SPLF" stands for Security, Performance, Load Balancing and Failover. This special server is used as a collaborator that provides services and resources to one or more DataFlex WebApp Servers executing applications.
The SPLF Server is the HTTP interface for all application processing user requests. It intercepts user HTTP requests and directs them to one or more connected application servers. The application server(s) return processed requests through the SPLF server. Details of the four valuable functions provided by an SPLF server are:
  • Security – The network connection between the SPLF server and the application servers attached to it can be configured using non-internet, Network Address Translation (NAT) addresses and other firewall mechanisms. In such a configuration, the SPLF server is internet connected – it has a public IP address. The application server(s) connection to the SPLF server will have internal, non-internet-exposed, NAT addresses that preclude direct access by internet users. With this configuration, applications and, just as importantly, application data, are never accessible from the internet providing a highly secure environment.
  • Performance – When IIS and DataFlex Web Framework applications are run on the same server instance, a significant portion of the computing capacity of the server is used by IIS – the Microsoft HTTP server program. This can significantly limit the computing capacity of the server available to the Web Applications (sometimes as little as 50% of the server’s resources are available for application processing). By moving the overhead of IIS to a separate SPLF server, the majority of an application server’s resources can be devoted to processing user requests. More server capacity = more performance and more application processing power per server instance.
  • Load Balancing – An SPLF server can also distribute or “balance” user requests among 2 to 255 clustered DataFlex WebApp Servers for high-capacity application processing. Each DataFlex WebApp Server will have the security and performance benefits described above. Load balancing is accomplished using tables hosted on the SPLF server that define the processing capability of each individual application server in the cluster. The SPLF server then assigns requests to each application server according to its individual, administrator defined capacity to handle requests. As load grows, application processing capability can scale easily and transparently by simply adding another application server instance to the cluster and including it in the list of available servers. If application server maintenance is required, temporarily removing an application server from the cluster list stops incoming requests and distributes them to other available servers. This flexible cluster design allows for the use of servers of varying levels of capacity and only assigning a server in the cluster with a load that it is capable of processing.
  • Failover - In addition to distributing load, in the event that an application server in the cluster fails, the SPLF server will automatically sense the failure, remove the failed server from the cluster and distribute incoming requests to or among the remaining active server(s).
An SPLF server runs on its own dedicated server instance. To keep licensing simple, the entitlement to connect to an SPLF server is licensed as a low-cost add-on fee to the application server license price. SPLF Servers can be connected to DataFlex WebApp Servers using either Web Client or Web Application licensing.
DataFlex WebApp Evaluation Server
An embeddable, ready-to-install, DataFlex WebApp Server for distributing trial or evaluation commercial web applications is included with Visual DataFlex 17.1. The Evaluation Server ceases to operate 60 days after installation on a given computer system. Specific terms and conditions of use are defined in the License Agreement. An Evaluation Web Application Server can be “activated in place” to enable a customer to begin production use an application without re-installation.
More information
For more information about VDF licensing options, contact your local Data Access Worldwide distributor or send an e-mail to


Download Visual DataFlex | Subscribe | Contact