In a preferred embodiment, the present invention comprises an authentication engine, an authentication host, and a plurality of {HEAD ~ providers} coupled to the host, each provider implementing {TAIL ~ a selected authentication scheme} 
In a preferred embodiment , the present invention comprises an authentication engine , an authentication host , and a plurality of { HEAD ~ providers } coupled to the host , each provider implementing { TAIL ~ a selected authentication scheme }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL