The SCTE/ISBE has approved two new standards.
SCTE 250 2019, "Real-time Event Signaling and Management API," details the interfaces between a Signal Acquisition System (SAS) and a Signal Decision System (SDS) in order to support signal and manifest processing. The APIs support synchronous signal processing, asynchronous signal processing, and processing of both linear and file-based content.
SCTE 254 2019, "Content Encoding Profiles 3.0 Specification (Closed Specification)," defines the content specifications for use with encoding systems, asset management, and distribution. It does not define a distribution method nor define all aspects of the cable system infrastructure that content may encounter during distribution and playback.
Both standards are available at https://www.scte.org/SCTE/Standards/Download/SCTE/Standards/Download_SCTE_Standards.aspx.