On Providing Survivable QoS Services in the Next Generation Internet”, supported in part by NSF grant NCR 9506652 and DARPA under agreement No

Abstract — In this paper we present a comparative study of two schemes to provide survivability for guaranteed QoS connections in a possible Next Generation Internet network architecture. In the first scheme a QoS connection is provided standby backup resources on a dis-joint path by reserving resources on both the working and backup path. In order to reduce the amount of backup resources required a method for sharing backup resources when the working connections have dis-joint routes has been included. In the second scheme a dynamic search for restoration resources is conducted over a preplanned set of alternate paths upon notification of a failure. A simulation based performance study shows that the first scheme results in much higher connection blocking under normal operations, slightly faster restoration times, and longer transient congestion times after fault recovery due to non-optimal backup routing. I