1. An advanced extensible interface 4 (AXI4) topology, comprising: a main entity; parallel sub entities comprising a first sub entity having a first functionality and a second sub entity comprising parallel third sub entities having a second functionality, which is different from the first functionality, and a controllable element in series with the parallel third sub entities; and an AXI4 interconnect element serially interposed between the main entity and the parallel sub entities wherein, for a transaction issued by the main entity with an augmented address including first and second addresses: the first address is readable by the AXI4 interconnect element to select one of the first and second sub entities for transaction execution, and the second address is readable by the controllable element to select one of the third sub entities for transaction execution.