A shared I/O subsystem for providing network protocol management for a
plurality of computer systems. The shared I/O subsystem includes a
plurality of I/O interfaces where each of the I/O interfaces operatively
couples one of the computer systems to the shared I/O subsystem. The
shared I/O subsystem also includes an I/O management link that
operatively interconnects the I/O interfaces, and a link layer switch
that communicatively couples to each of the I/O interfaces. The link
layer switch receives a data packet from one of the I/O interfaces and
directs the data packet to one or more of the other ones of the I/O
interfaces. The I/O interfaces may form a local area network within the
shared I/O subsystem.