Source : Free On-Line Dictionary of Computing

Internetwork Packet eXchange
     
         (IPX) A {network layer} {protocol} initially
        developed at {XEROX Corporation} and made popular by {Novell,
        Inc.} as the basic protocol in its {Novell NetWare} {file
        server} {operating system}.
     
        A {router} with IPX routing can interconnect {Local Area
        Networks} so that Netware {clients} and {servers} can
        communicate.
     
        The {SPX} {transport layer} protocol runs on top of IPX.
     
        (1997-03-04)