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