{HEAD ~ The single waveguide} can be connected, tail in mouth, to provide a low loss ring concentrator to which receiving and {TAIL ~ transmitting nodes} are coupled via associated node switches 
{ HEAD ~ The single waveguide } can be connected , tail in mouth , to provide a low loss ring concentrator to which receiving and { TAIL ~ transmitting nodes } are coupled via associated node switches
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH