Aggressive transmissions of short messages over redundant paths

Fault-tolerant computer systems have redundant paths connecting their components. Given these paths, it is possible to use aggressive techniques to reduce the average value and variability of the response time for short, critical messages. One technique is to send a copy of a packet over an alternate path before it is known whether the first copy failed or was delayed. A second technique is to split a single stream of packets over multiple paths. The authors analyze both approaches and show that they can provide significant improvements over conventional, conservative mechanisms