Frames are the shape that Data link layer (DLL) encapsulate data in. When they move down into the PHY layer they converted into bits (0's and 1's). Type of framing technology depends on the network technology you are using. For example, WAN utilizes, frame relay, ATM and MPLS frames. for LANs ethernet dominates. when these frames reaches wires or radio interface, they are treated independently from each other. They may take different paths. I hope this answer is what you are looking for