PROTOCOL SOFTWARE AND ETHERNET WIRING:

 All wiring methods use identical Ethernet specifications. e.g. they need same message format. They need same CSMA/CD algorithems. They may mix different methods in an Ethernet.

 NICs can give all three-connection technologies. The protocol software can't distinguish among wiring methods. The NIC is given in the figure below with three connectors.

Figure 

HUBS:

 They are needed for extension of connection with multiplexing concept. They are sometimes known Ethernet-in-a-box. It is effectively a very minimized Ethernet with very maximized AUI cables. It can be connected into bigger Ethernet.