On minimizing end-to-end delay with optimal traffic partitioning

Multipath transport provides higher usable bandwidth for a session. It has also been shown to provide load balancing and error resilience for end-to-end multimedia sessions. Two key issues in the use of multiple paths are 1) how to minimize the end-to-end delay, which now includes the delay along the paths and the resequencing delay at the receiver, and 2) how to select paths. This paper presents an analytical framework for the optimal partitioning of real-time multimedia traffic that minimizes the total end-to-end delay. Specifically, it formulates optimal traffic partitioning as a constrained optimization problem using deterministic network calculus and derives its closed-form solution. Compared with previous work, the proposed scheme is simpler to implement and enforce. This analysis also greatly simplifies the solution to the path selection problem as compared to previous efforts. Analytical results show that for a given flow and a set of paths, a minimal subset can be chosen to achieve the minimum end-to-end delay with O(N) time, where N is the number of available paths. The selected path set is optimal in the sense that adding any rejected path to the set will only increase the end-to-end delay.