IT Service Directory (ITSD)
The IT Service Directory (ITSD) will significantly expand the capabilities of the TPS+Plus system in the areas of symbol aliasing, data blending, and source switching. The Service Directory will be a metadata server that will be used by the Middleware2 components to retrieve information about how to fulfill a subscription request. The metadata returned by the ITSD can include: - Symbol translation or aliasing, allowing client applications to request items using symbology that is different from the symbology used by the IT Exchange Servers (ITES) to publish data. This will allow multiple symbologies to be supported simultaneously on a single system and can provide symbology cross referencing to client applications where required.
- Data blending and synthetic record creation: the Middleware2 components will be capable of constructing an object by combining fields from multiple sources in real-time. The metadata provided by the ITSD determines the contents of the data object and how/where each field will be sourced.
- Source switching, allowing data sources for individual fields or entire records to be redefined at any time. The ITSD is a real-time service and any changes to the metadata will take effect immediately; all affected Middleware2 components will be notified to apply the change.
A unique feature of the IT Service Directory is that it does all this without adding an additional processing layer, or additional message hops, to the data, and thus maintains the “flat” architecture of the TPS+Plus system. The metadata is retrieved from the ITSD by the Middleware2 infrastructure when an item is requested. The Middleware2 components then construct the blended object on the “fly” by using the meta data to directly subscribe to the data sources and delivers a completed object to the subscribing application. This minimizes the additional latency introduced by not having to route updates through an additional component.