The invention includes a method and apparatus for enabling multipoint bus access. In one example, the open ring-architecture bus includes a boundary scan bus including a plurality of bus access points adapted for interfacing with a plurality of circuit packs, a first termination circuit coupled to a first end of the bus, and a second termination circuit coupled to a second end of the bus. The first termination circuit and second termination circuit are adapted for terminating signaling on the boundary scan bus. The open-ring architecture bus provides a master circuit pack a multipoint access capability such that the master circuit pack may be disposed at any of the plurality of bus access points. In one example, signaling includes signaling operable for performing hierarchical system testing, including boundary scan testing. In another example, signaling includes upgrade signaling operable for performing firmware upgrades, software upgrades, and like circuit pack upgrades.