From https://labs.etsi.org/rep/saref/saref-portal/-/issues/3 SAREF4ENVI, SAREF4WEAR, SAREF4LIFT, SAREF4WATR, all define some kind of communication protocols and interfaces. Only SAREF4LIFT uses the patterns from SAREF4SYST for describing communication protocols. See Figure 18 at https://saref.etsi.org/saref4lift/v1.1.1/ SAREF4EHAW defines s4ehaw:CommunicationProtocol SAREF4ENVI defines s4envi:usesCommunicationInterface and s4envi:usesCommmunicationProtocol, and s4envi:System, which from its definition read more like a CommunicatingSystem DP s4watr:operatesAtRadioFrequency would best be applied to some ontology of communication protocols. Other extensions SAREF4LIFT, SAREF4EHAW, SAREF4WEAR, do define communication interfaces and protocols. Some harmonization would be required.