Application Connectivity

KEPServerEX supports leading industrial automation standards and automation and IT interfaces for accessibility to client applications.

The KEPServerEX connectivity platform offers simultaneous accessibility to client applications through an ever-growing list of supported industry standards, proprietary technologies, and native client interfaces. Expand the topics below to learn more.

DDE Native Interface

Dynamic Data Exchange (DDE) allows applications to share data in a Microsoft Windows environment. As such, the server provides access to DDE applications that support one of the following DDE formats:

  • CF_Text and XL_Table are standard DDE formats developed by Microsoft for use with all DDE-aware applications.
  • Advanced DDE is a variation of the normal CF_Text format defined by Rockwell Automation that allows large amounts of data to transfer between applications at higher rates of speed.
  • Network DDE (Net DDE) is the standard for remote DDE connection as defined by Microsoft that uses the CF_Text format.

Supported Formats: CF_Text, XL_Table, Advanced DDE, Network DDE

FastDDE/SuiteLink Native Client Interface

FastDDE is a DDE format defined by Wonderware Corporation that enables large amounts of data to transfer between applications at higher speed (and with better error handling) than generic DDE. SuiteLink is a client/server communication method that has succeeded FastDDE. It is TCP/IP-based and has improved bandwidth and speed. Both FastDDE and SuiteLink are supported by all Wonderware client applications.

iFIX Native Client Interface

The iFIX native client interface simplifies the connection task by allowing a direct connection to the local iFIX application without the use of the iFIX OPC Power Tool. When supported, this interface also has the ability to refine the connection between the server and the iFIX Process Database (PDB).


The Message Queuing Telemetry Transport (MQTT) protocol is a publish/subscribe protocol designed for SCADA and remote networks. It focuses on minimal overhead (2-byte header) and is recommended when bandwidth is limited.


Open Database Connectivity (ODBC) is an open standard API developed by Microsoft for accessing a database (such as Microsoft Access, dBase, Excel, and more).


OPC .NET is a family of APIs provided by the OPC Foundation that leverage Microsoft's .NET technology and allow .NET clients to connect to the server. KEPServerEX supports OPC .NET 3.0 WCF, formally known as OPC Xi. Unlike other OPC .NET APIs, OPC .NET 3.0 uses Windows Communication Foundation (WCF) for connectivity, avoiding DCOM issues and providing secure communication via multiple communications bindings, consolidation of the OPC Classic interfaces, and the simple development, configuration, and deployment of Windows environments.

KEPServerEX adds OPC .NET 3.0 support using a customized version of the OPC .NET 3.0 WCF Wrapper supplied by the OPC Foundation.

Supported Versions: 1.20.2

OPC Alarms and Events (AE)

OPC Alarms and Events (AE) is a specification developed by the OPC Foundation to standardize the way that alarm and event information is shared among systems. Using the standard, AE clients can receive alarms and event notices for equipment safety limits, system errors, and other abnormal situations.

Supported Versions: 1.0 and 1.10

OPC Data Access (DA)

"OPC" stands for Open Platform Communications in industrial automation and the enterprise systems that support industry. It is a client/server technology where one application acts as the server (providing data) and another acts as a client (using data).

OPC is composed of a series of standards specifications. OPC Data Access is the most prolific and enables data exchange between multi-vendor devices and control applications without proprietary restrictions. An OPC server can communicate data continuously among PLCs on the shop floor, RTUs in the field, software applications on desktop PCs, and much more. OPC compliance makes continuous real-time communication possible (even when the hardware and software are from different vendors).

OPC Data Access 1.0a was the original specification developed by the OPC Foundation in 1996. Although it continues to be supported by many of the OPC client applications in use today, OPC Data Access 2.0 Enhanced OPC better utilizes the underlying Microsoft COM technology. OPC Data Access 3.0 is the latest version of the OPC DA interface.

Supported Versions: 1.0a, 2.05a, 3.0

OPC Historical Data Access (HDA)

The OPC Historical Data Access (HDA) specification defines query methods and analytics that may be applied to historical data. It defines behaviors for many well-known aggregates, which are methods that summarize data values over a particular time domain at the time of data retrieval. It can be used to create a simple trend data server and more complex data compression and analysis servers that are capable of providing summary data, history updates, history data annotations, and backfilling.

Supported Versions: 1.20.

OPC Unified Architecture (UA)

OPC Unified Architecture is an open standard created by the OPC Foundation with help from dozens of member organizations. It offers a secure method for remote client-to-server connectivity without depending on Microsoft COM or DCOM technology, and has the ability to connect securely through firewalls and across the Internet, WAN, or LAN. Kepware’s implementation of the UA server supports optimized binary TCP and the DA data model.

Supported Version: 1.02 optimized binary TCP


The Representational State Transfer (REST) protocol is a stateless model for accessing resources on the server via requests.


Simple Network Management Protocol (SNMP) is a protocol developed by the Internet Architecture Board for exchanging information between network devices.


The Splunk API enables the streaming of real-time industrial data into Splunk® software and Cloud services.

Thin-Client Terminal Server

Windows Remote Desktop (formerly called Terminal Services) is a Microsoft Windows component that allows users to access data and applications on a remote computer over a network. It also enables communications servers to be configured via remote client machines.

ThingWorx Native Interface

The ThingWorx Native Interface provides real-time, bi-directional industrial controls data to the ThingWorx® Industrial Innovation Platform via the ThingWorx AlwaysOn™ protocol. Users can quickly and easily connect and configure ThingWorx-developed applications to KEPServerEX. ThingWorx services enable users to browse, read, write, and interact with KEPServerEX.