A primary multi-layer protocol stack that allows a secondary multi-layer protocol stack to communicatively couple into one or more of its layers. End point device circuitry implements both the primary and secondary protocol stacks. A communication application running on the end point device initiates interaction, e.g., a session, via a primary radio and primary intermediate protocol stack layers. Based on a change in communication characteristics, for example, an operation is invoked to bridge between one of the intermediate protocol stack layers of the primary stack to one from the secondary stack. Such bridging establishes a secondary pathway via the secondary radio. The primary and secondary radios may support the same or differing protocols. To avoid having to fully reestablish a session, at least one session parameter is carried forward through the bridge. The bridge may have multiple entry points in and out of both protocol stacks and operate as two half-duplex bridges.