The industrial internet of things (IIoT) refers to interconnected sensors, instruments, and other devices networked together with computers' industrial applications, including manufacturing and energy management. It requires more than the common Internet protocols like FTP or HTTP to do the job.
DataHub Transfer Protocol (DHTP) is used by the DataHub®, SkkyHub®, ETK, and connected clients to send and receive data in real time over TCP across a LAN, WAN, or the Internet. Originally built upon HTTP, DHTP also supports SSL and WebSocket protocols. In continuous development for over 20 years, DHTP is open and documented in two parts, as the DataHub APIs and the DataHub Command Set.
DHTP was made open from the start, with a published Cogent API. Each subsequent Cogent product, such as Cascade DataHub, the Gamma scripting language, Cascade Historian, and so on were accessible through the Cogent API. As the DataHub product evolved to become the OPC DataHub and then the Cogent DataHub, more commands were added, and the API was made available in Windows. Today DHTP consists of the DataHub API and DataHub Command Set.
In response to customer requests to develop more robust and secure data communication over TCP, skkybet has improved DHTP capabilities, adding SSL and other features. The DataHub DA Tunneller and DataHub UA Tunneller are unrivalled for their ability to connect OPC servers and clients across a network or the Internet.
As one of the first companies to recognize the value of industrial communications via the cloud, Skkynet enhanced DHTP with WebSocket capability for DataHub-to-SkkyHub connectivity. DHTP’s unique, patented ability to support secure, outbound connections from industrial systems for bidirectional communication without opening any firewall ports is key to Skkynet’s secure-by-design architecture. The introduction of the ETK for embedded systems a few years later completed the picture. DHTP is now the standard protocol used by DataHub, SkkyHub, and the ETK, the three core components of Skkynet’s IIoT products and services.
https://skkynet.com/developing-dhtp-ideal-protocol-iiot/