Figure 1 shows the interaction between a controller, a UCH and a target.

The UCH is further composed into the following parts: UIList, UIPM, UCH (Socket Layer), TDM and TA.

The following interactions take place, indicated by arrows in the figure. For some interactions, proprietary or standardized interfaces are used on either end. Order follows approximate chronogical order in a running system.

• 2-way interaction between UCH (Socket Layer) (TDMListener interface) and TDM (ITDM interface). Communication via API.
• 2-way interaction "Discovery" between TDM (proprietary interface) and Target. Communication via any protocol.
• 2-way interaction between UCH (Socket Layer) (ITAListener interface) and TA (ITA interface). Communication via API.
• 2-way interaction "Control" between TA (proprietary interface) and Target. Communication via any protocol.
• 1-way interaction between UCH (Socket Layer) and UIList. Internal communication.
• 1-way interaction "Discovery" between UIList and Controller. Communication via HTTP or UPnP / Bonjour.
• 2-way interaction between UIPM (IUIPM interface) and UCH (Socket Layer) (IUIPMListener interface). Communication via API.
• 2-way interaction "Control" between UIPM (proprietary interface) and Controller. Communication via any protocol (e.g. HTTP).