ST-TCP (Server fault-Tolerant TCP) is an extension of TCP
to tolerate TCP server failures. Server fault tolerance is
provided by using an active-backup server that keeps track
of the state of a TCP connection. The backup server takes
over the TCP connection if the primary server fails. This
take-over is fast, seamless, and completely transparent to
the client. This paper provides a system demonstration of
a new ST-TCP prototype. The new prototype incorporates
a performance-enhanced architecture and addresses applica-
tion failure scenarios. Five experiments using this prototype
are proposed to demonstrate the following useful features: (1)
Client-transparent, seamless failover; (2) Insignificant per-
formance overhead of ST-TCP during failure-free periods;
and (3) An ability to tolerate all single crash failures at the
hardware and operating system levels, and, most crash fail-
ures at the application level.